feasible'' (see the Summary and Explanation section on Respiratory
Protection for more information).
    CISC submitted comments suggesting that the technological
feasibility analysis was incomplete because it did not cover every
construction-related task for which there is the potential for exposure
to silica dust. It listed more than 20 operations, including cement
mixing, cutting concrete pavers, demolishing drywall or plaster walls/
ceilings, overhead drilling, demolition of concrete and masonry
structures, and grouting floor and wall tiles, that it stated OSHA must
examine in order to establish feasibility, in addition to the
application groups already covered by OSHA's analysis (Document ID
2319, pp. 19-21). CISC asserted that, because of the many types of
silica-containing materials used in the construction industry, as well
as the presence of naturally occurring silica in soil, additional data
collection and analysis by OSHA should be conducted before promulgating
a final rule (Document ID 2319, pp. 25-26; 4217, p. 3).
    As explained in the NPRM, OSHA's analysis for construction focuses
on tasks for which the available evidence indicates that significant
levels of respirable crystalline silica may be created, due primarily
to the use of powered tools or large equipment that generates visible
dust. OSHA notes that many of the examples of tasks for which CISC
requested additional analysis are tasks involving the tools and
equipment already covered in this feasibility analysis. For example,
overhead drilling is addressed in section IV-5.4 Hole Drillers Using
Handheld or Stand-Mounted Drills, and the demolition of concrete and
masonry structures is addressed in section IV-5.3 Heavy Equipment
Operators. In other cases, such as for concrete mixing, there are no
sampling data in the record to indicate that the task is likely to
result in 8-hour TWA exposures above the action level. Exposure can
occur when cleaning dried cement, and the feasibility of control
measures to reduce exposures when cleaning out the inside of cement
mixers is discussed in section IV-4.17 Ready Mix Concrete. Other tasks
listed by CISC involve working with wet or intact concrete, which is
unlikely to result in 8-hour TWA exposures above the action level.
Further, CISC did not submit to the record any air monitoring data to
support its assertion that these activities result in significant
exposures. Therefore, OSHA has not added these additional activities to
the feasibility analysis.
4. Feasibility Findings for an Alternative Permissible Exposure Limit
of 25 [mu]g/m\3\
    In the NPRM, OSHA invited comment on whether it should consider a
lower PEL because it determined there was still significant risk at the
proposed PEL of 50 [mu]g/m\3\ (78 FR 56288, September 12, 2013). OSHA
has determined that the rule's PEL of 50 [mu]g/m\3\ is the lowest
exposure limit that can be found to be technologically feasible based
on the rulemaking record. Specifically, OSHA has determined that the
information in the rulemaking record either demonstrates that the
proposed alternative PEL of 25 [mu]g/m\3\ would not be achievable for
most of the affected industry sectors and application groups or the
information is insufficient to conclude that engineering and work
practice controls can consistently reduce exposures to or below 25
[mu]g/m\3\. Therefore, OSHA cannot find that the proposed alternative
PEL of 25 [mu]g/m\3\ is achievable for most operations in the affected
industries, most of the time.
    The UAW submitted comments and data to the record, maintaining that
a PEL of 25 [mu]g/m\3\ is technologically feasible. As evidence, it
submitted exposure data from a dental equipment manufacturing plant and
two foundries (Document ID 2282, Attachment 3, pp. 7-8; 4031, pp. 3-8)
showing that exposures to silica in these establishments were
consistently below 25 [mu]g/m\3\ TWA. However, OSHA cannot conclude
that exposure data from three facilities is representative of the wide
array of facilities affected by the rule or sufficient to constitute
substantial record evidence that a PEL of 25 [mu]g/m\3\ is
technologically feasible in most operations most of the time.
    Although available exposure data indicate that exposures below 25
[mu]g/m\3\ have already been achieved for most employees in some
general industry sectors and construction application groups (e.g.,
dental laboratories, jewelry, and paint and coatings in general
industry, and drywall finishers and heavy equipment operators
performing excavation in construction), the relatively low exposures
can be attributed to the effective control of the relatively small
amounts of dust containing silica generated by employees in these
industries and application groups. Further extrapolation to other
sectors or groups with higher baseline exposures or more challenging
control situations is not warranted, however.
    For most of the industries and application groups included in this
analysis, a review of the sampling data indicates that an alternative
PEL of 25 [mu]g/m\3\ cannot be achieved with engineering and work
practice controls. OSHA finds that engineering and work practice
controls will not be able to consistently reduce and maintain exposures
to an alternative PEL of 25 [mu]g/m\3\ in the sectors that use large
quantities of silica containing material, including foundries (ferrous,
nonferrous, and non-sandcasting), concrete products, and hydraulic
fracturing, or have high energy operations, such as jackhammering and
crushing machines.
    For instance, in the ferrous foundry industry, the baseline median
exposure in the profiles exceeds 50 [mu]g/m\3\ for 6 of the 12 job
categories analyzed: Sand system operators, shakeout operators,
abrasive blasting operator, cleaning/finishing operators, maintenance
operators, and housekeeping employees. OSHA concluded that engineering
and work practice controls can reduce TWA exposures to 50 [mu]g/m\3\ or
less for most of these operations most of the time. However, because
large amounts of silica-containing sand is transported, used, and
recycled to create castings, OSHA cannot conclude that available
controls can reduce exposures to or below 25 [mu]g/m\3\ in any step of
the

production process. Additionally, high energy operations in foundries
can create concentrations of respirable silica above 25 [mu]g/m\3\. For
example, the shakeout process is a high energy operation using
equipment that separates castings from mold materials by mechanically
vibrating or tumbling the casting. The dust generated from this process
causes elevated silica exposures for shakeout operators and often
contributes to exposures for other employees in a foundry. The
effectiveness of dust controls on shakeout operations was demonstrated
at three foundries that implemented various dust controls in the
shakeout area (e.g., shakeout enclosure added, ventilation system
improved, conveyors enclosed and ventilated); full-shift samples taken
by or for OSHA measured exposures for shakeout operators ranging from
less than or equal to 13 [mu]g/m\3\ to 41 [mu]g/m\3\ (Document ID 1365,
pp. 2-51; 1407, p. 20; 0511, p. 2). These readings were obtained in
foundries that had made a systematic effort to identify and abate all
sources of dust emission with the establishment of an abatement team
consisting of an engineer, maintenance and production supervisors, and
employees. TWA exposures for the shakeout operators were reduced to
less than 50 [mu]g/m\3\, but two of the four measurements in this well-
controlled facility exceeded 25 [mu]g/m\3\ (see Chapter IV 4.8.1 of the
FEA). Other industry sectors that use substantial quantities of
crystalline silica as a raw material include refractories, glass
products, mineral processing, structural clay and cement products. OSHA
finds that the available evidence on exposures at facilities in these
industries in which controls have been implemented indicates most
exposures are typically between 25 [mu]g/m\3\ and 50 [mu]g/m\3\.
    For other general industry sectors, OSHA has insufficient data to
demonstrate that engineering and work practice controls will reduce
exposures to or below 25 [mu]g/m\3\ most of the time (see Chapter IV of
the FEA). For example, it is not evident that exposures can be reduced
to 25 [mu]g/m\3\ for four out of five jobs analyzed in the pottery
sector, for two out of three job categories in the structural clay
sector, and for two jobs in the porcelain enameling sector.
    OSHA has also determined that application groups in construction
that use large quantities of silica containing material or involve high
energy operations will not be able to consistently achieve 25 [mu]g/
m\3\ (e.g. tuck pointing/grinding and rock and concrete drilling).
These operations cause employees to have elevated exposures even when
available engineering and work practice controls are used. Examples
include using jackhammers during demolition of concrete and masonry
structures, grinding concrete surfaces, using walk-behind milling
machines, operating rock and concrete crushers, and using portable saws
to cut concrete block. For instance, jackhammering is a high energy
operation and OSHA finds that when employees perform this operation for
four hours or less in a shift, most employees using jackhammers
outdoors experience levels at or below 50 [mu]g/m\3\ TWA but not
reliably at or below 25 [mu]g/m\3\. The use of portable cut-off saws (a
type of handheld power saw) is also a high energy operation that can
lead to exposures over 25 [mu]g/m\3\. Due to energy applied to the
material being cut from the rapid rotation of the circular blade, the
dust generated can be difficult to control; available data indicate
that exposures will often exceed 25 [mu]g/m\3\ TWA, even when the
portable cut-off saw is used with water for dust suppression. Evidence
in the record indicates that, for most of the other construction
operations examined, use of feasible engineering and work practice
controls will still result in frequent exposures above 25 [mu]g/m\3\.
For other tasks in construction application groups, OSHA has
insufficient data to demonstrate that engineering and work practice
controls will reduce exposures to or below 25 [mu]g/m\3\ most of the
time (see Chapter IV of the FEA).
    Therefore, OSHA concludes that 50 [mu]g/m\3\ as an 8-hour TWA is
the lowest feasible exposure limit that the record demonstrates can be
applied to most general industry, maritime, and construction operations
without the excessive use of respirators. OSHA also concludes that it
would hugely complicate both compliance and enforcement of the rule if
it were to set a PEL of 25 [mu]g/m\3\ for a minority of industries or
operations where it would be technologically feasible and a PEL of 50
[mu]g/m\3\ for the remaining industries and operations where
technological feasibility at the lower PEL is either demonstrably
unattainable, doubtful or unknown. OSHA is not under a legal obligation
to issue different PELs for different industries or application groups,
but may exercise discretion to issue a uniform PEL if it determines
that the PEL is technologically feasible for all affected industries
(if not for all affected operations) and that a uniform PEL would
constitute better public policy (see Section II, Pertinent Legal
Authority (discussing the chromium (VI) decision)). In declining to
lower the PEL to 25 [mu]g/m\3\ for any segment of the affected
industries, OSHA has made that determination here.

E. Costs of Compliance

Overview
    This section assesses the costs to establishments in all affected
industry sectors of reducing worker exposures to silica to an 8-hour
time-weighted average (TWA) permissible exposure limit (PEL) of 50
[mu]g/m\3\--or, alternatively, for employers in construction to meet
the Table 1 requirements--and of complying with the standard's
ancillary requirements. This cost assessment is based on OSHA's
technological feasibility analysis presented in Chapter IV of the FEA;
analyses of the costs of the standard conducted by OSHA's contractor,
Eastern Research Group; testimony during the hearings; and the comments
submitted to the docket as part of the rulemaking process.
    OSHA estimates that the standard will have a total cost of $1,029.8
million per year in 2012 dollars. Of that total, $370.8 million will be
borne by the general industry and maritime sectors, and $659.0 million
will be borne by the construction sector. Costs originally estimated
for earlier years in the PEA were adjusted to 2012 dollars using the
appropriate price indices. In general, all employee and supervisor
wages (loaded) were from the 2012 BLS OES (Document ID 1560); medical
costs were inflated to 2012 dollars using the medical services
component of the Consumer Price Index; and, unless otherwise specified,
all other costs were inflated using the GDP Implicit Price Deflator
(Document ID 1666).
    All costs were annualized using a discount rate of 3 percent,
which--along with 7 percent \26\--is one of the discount rates
recommended by OMB. Annualization periods for expenditures on equipment
are based on equipment life, while there is a 10-year annualization
period for one-time costs. Note that the benefits of the standard,
discussed in Section VII.G of this preamble and in Chapter VII of the
FEA, were annualized over a 60-year period to reflect the time needed
for benefits to reach steady-state values. Therefore, the time horizon
of OSHA's complete analysis of this rule is 60 years. Employment and
production in affected

industries are being held constant over this time horizon for purposes
of the analysis. All non-annual costs are estimated to repeat every ten
years over the 60-year time horizon, including one-time costs that
recur because of changes in operations over time or because of new
entrants that must comply with the standard.\27\ Table VII-10 shows, by
affected industry in the sectors of general industry and maritime,
annualized compliance costs for all establishments, all small entities
(as defined by the Small Business Act and the Small Business
Administration's (SBA's) implementing regulations; see 15 U.S.C. 632
and 13 CFR 121.201), and for all very small entities (those with fewer
than 20 employees). Table VII-11 similarly shows, by affected industry
in construction, annualized compliance costs for all entities, all
small entities, and all very small entities. Note that the totals in
these tables and all other tables in this chapter, as well as totals
summarized in the text, may not precisely sum from underlying elements
due to rounding.
---------------------------------------------------------------------------

    \26\ Appendix V-D of the FEA presents costs by NAICS industry
and establishment size category using, as alternatives, both a 7
percent discount rate and a 0 percent discount rate. In the
sensitivity analysis presented in Chapter VII of the FEA, OSHA
compares the estimated cost of the rule using the 3 percent discount
rate to the estimated cost using these alternative discount rates.
    \27\ To the extent one-time costs do not recur, OSHA's cost
estimates, when expressed as an annualization over a 10-year period,
will overstate the cost of the standard.
---------------------------------------------------------------------------

    OSHA's exposure profile, presented in Chapter III of the FEA,
represents the Agency's best estimate of current exposures (i.e.,
baseline exposures). Except for compliance with Table 1 in
construction, OSHA did not attempt to determine the extent to which
current exposures in compliance with the new silica PEL are the result
of baseline engineering controls or the result of other circumstances
leading to low exposures. This information is not needed to estimate
the costs of (additional) engineering controls needed to comply with
the new PEL, but it is relevant to estimate the costs of complying with
Table 1 in construction.
    For both construction and general industry/maritime, the estimated
costs for the silica rule represent the additional costs necessary for
employers to achieve full compliance with the new standard, assuming
that all firms are compliant with the previous standard. Thus, the
estimated costs do not include any costs necessary to achieve
compliance with previous silica requirements, to the extent that some
employers may not be fully complying with previously-applicable
regulatory requirements. OSHA almost never assigns costs for reaching
compliance with an already existing standard to a new standard
addressing the same health issues. Nor are any costs associated with
previously-achieved compliance with the new requirements included.
    Because of the severe health hazards involved, as well as current
OSHA regulation, the Agency expects that the estimated 11,640 abrasive
blasters in the construction sector and the estimated 3,038 abrasive
blasters in the maritime sector are currently wearing respirators as
required by OSHA's abrasive blasting provisions (29 CFR 1915.154
(referencing 29 CFR 1910.134)). Furthermore, an estimated 264,761
workers, including abrasive blasters, will need to use respirators at
least once during a year to achieve compliance with the new silica rule
in construction, and, based on the NIOSH/BLS respirator use survey
(NIOSH/BLS, 2003, Document ID 1492), an estimated 56 percent of
construction employees whose exposures are high enough that they will
need respirators under the new rule currently use such respirators.
OSHA therefore estimates that 56 percent of affected construction
employees already use respirators in compliance with the respirator
requirements of the final silica rule.
    Other than respiratory protection, OSHA did not assume baseline
compliance with any other ancillary provision, even though some
employers have reported that they currently monitor silica exposure,
provide silica training, and conduct medical surveillance.
    The remainder of this chapter is organized as follows. First, unit
and total costs by provision are presented for general industry and
maritime and for construction. Following that, the chapter concludes
with a summary of the estimated costs of the rule for all affected
industries.
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BILLING CODE 4510-26-C
1. Engineering Controls
a. General Industry and Maritime
    The engineering control section in Chapter V of the FEA covers
OSHA's estimates of engineering control costs for general industry and
maritime sectors. Oil and natural gas fracturing operations are
addressed separately because OSHA used a different methodology to
estimate engineering control costs for this application group. This
section will address OSHA's overall methodology, the methodology for
each category of costs (such as ventilation, housekeeping, conveyors),
issues specific to small entities, and issues specific to the hydraulic
fracturing industry. Within each of these discussions, this section
summarizes the methodology used in the PEA to estimate engineering
control costs, summarizes and responds to the comments on the PEA, and
summarizes the changes made to the methodology used in the PEA for the
FEA. Finally, the chapter presents OSHA's final estimates of
engineering control costs.
Introduction
    The PEA's technological feasibility analysis identified the types
of engineering controls that affected industries or sectors would need
in order to control worker exposures to at

or below the proposed PEL of 50 [mu]g/m\3\. Through its contractor,
Eastern Research Group (ERG), OSHA generated cost estimates for those
controls using product and technical literature, equipment vendors,
industrial engineers, industrial hygienists, and other sources, as
relevant to each item. Wherever possible, objective cost estimates from
recognized technical sources were used. Specific sources for each
estimate were presented with the cost estimates.
    Table V-4 of the PEA provided a list of possible controls on an
industry-by-industry basis and included details on control
specifications and costs. The basic information for the types of
controls needed was taken from the PEA's technological feasibility
analysis. The following discussion explains how OSHA developed and used
these estimates to prepare the aggregate costs of engineering controls
presented in the PEA.
    In developing engineering control cost estimates for the PEA, OSHA
made a variety of estimates about the size or scope of the engineering
or work practice changes necessary to reduce silica exposures in
accordance with the proposed rule. In some cases, OSHA estimated that
employers would need to install all new engineering controls. In other
cases, though, employers were expected to only need to add additional
ventilation capacity or improve maintenance for existing equipment. In
these cases, the costs were based on judgments of the amount of
incremental change (either additional capacity or additional
maintenance work) required per year. These estimates of the size or
scope of the necessary engineering or work practice changes reflected
representative conditions for the affected workers based on technical
literature (including National Institute for Occupational Safety and
Health (NIOSH) Health Hazard Evaluations), judgments of knowledgeable
consultants and industry observers, and site visits. A detailed list of
the specific costing assumptions and information sources for each
control, grouped by job category or industry sector, was shown in PEA
Appendix V-A, Table V-A-1.
    In order to estimate costs in a consistent manner, OSHA, in the
PEA, estimated all costs on an annualized basis. For capital costs,
OSHA calculated the annualized capital cost, using a three percent
discount rate over the expected lifetime of the capital item. The
capital costs for long-lasting capital items (such as ventilation
system improvements) were annualized over ten years. OSHA estimated
that, in the general industry and maritime sectors, any capital
expenditure would also entail maintenance costs equal to ten percent of
the value of the capital investment annually.
General Methodology
General Methodology: Per-Worker Basis and Treatment of Overexposures
for Cost Calculations
PEA Estimates
    OSHA, in the PEA, estimated control costs on a per-worker basis.
Costs were related directly to the estimates of the number of workers
needing controls (i.e., workers exposed over 50 [mu]g/m\3\). OSHA
divided engineering control costs into two categories: (1) Those only
needed by establishments with employees exposed to levels of silica
that exceeded the preceding general industry PEL of 100 [mu]g/m\3\; and
(2) those applicable to all establishments where workers were exposed
to levels of silica above the proposed PEL (whether just above 50
[mu]g/m\3\ or also above 100 [mu]g/m\3\). It should be noted that the
maritime sector has been subject to a different preceding PEL of 250
[mu]g/m\3\. The PEA estimates were presented in the PEA cost analysis
tables. The overwhelming majority of the costs (90 percent of all
engineering control costs and 85 percent of costs associated with
meeting the preceding PEL of 100 [mu]g/m\3\) were associated with the
second category (controls applicable to all establishments with
exposures above the proposed or preceding PEL). Because OSHA is not
accounting for the costs of controls necessary to reach the preceding
PEL, the PEA focused on controls that may be needed to meet the new
PEL. OSHA derived per-worker costs by examining the controls needed for
each job category in each industry and dividing the cost of that
control by the number of workers whose exposures would be reduced by
that control. OSHA then multiplied the estimated per-worker control
cost by the number of workers exposed between the proposed (new) PEL of
50 [mu]g/m\3\ and the preceding PEL of 100 [mu]g/m\3\. The numbers of
workers in this category were based on the exposure profiles for at-
risk occupations developed in the technological feasibility analysis in
Chapter IV of the PEA and the estimates of the number of workers
employed in these occupations were developed in the industry profile in
Chapter III of the PEA. The exposure profile information was determined
to be the best available data for estimating the need for incremental
controls on a per-worker basis.
    In general, in the PEA, OSHA inferred the extent to which exposure
controls were already in place from the distribution of overexposures
among the affected workers. Thus, if most exposures in a facility were
above the preceding PEL, OSHA broadly interpreted this as a sign of
limited or no controls, and if most exposures were below the proposed
(new) PEL of 50 [mu]g/m\3\, this would be indicative of having adequate
controls in place. OSHA calculated the costs of controls per exposed
worker in each job category and assigned this cost to the total number
of employees exposed between the proposed (new) PEL and the preceding
PEL. For example, if a control cost $1,000 per year and covered 4
employees, the cost per employee would be $250 per year. If 100
employees in the job category were exposed between the preceding and
proposed (new) PEL, then the total costs would be $250 times 100
employees or $25,000. No costs were estimated for employees currently
exposed above the preceding PEL or below the proposed (new) PEL.
    OSHA determined that multiple controls would be needed for almost
all jobs in general industry in order reduce exposures from baseline
conditions to meeting the proposed (new) PEL of 50 [mu]g/m\3\. Some of
these controls cover a group of workers, while others might be
individualized (such as daily housekeeping by each individual worker).
Comments on the Per-Worker Basis and Proportionality of Costs
    URS, speaking for the American Chemistry Council (ACC), argued that
OSHA's approach underestimated the costs of controls because it based
costs on controls per worker instead of controls per facility (Document
ID 2307, Attachment 8, p. 4). Since OSHA did not provide a distribution
of exposures by facility or provide facility-specific information, URS
used data in the record to create its own models to account for
facility size. URS described its approach as follows:

    URS created three statistical binomial distributions of
overexposed workers, one for each of the three facility sizes, using
OSHA's estimate of the percentage of over-exposed workers for that
job. The result was a binomial distribution curve indicating the
percentage of overexposed workers for each job category for each
size-specific ``model facility.''
    For each binomial distribution, the peak of the distribution
curve centers on the average number of overexposed workers per
facility for that job description according to OSHA's estimate
(Document ID 2307, Attachment 8, p. 7).

    In taking this approach, URS erroneously assumed that the

distribution of overexposed workers per facility was random, as
evidenced by its use of a binomial distribution to approximate
overexposures per facility within each of three facility sizes
(Document ID 2307, Attachment 8, p. 7). Examination of the spreadsheet
URS provided shows that this approach approximately doubles the number
of controls needed and, and for this reason, doubles the total cost of
engineering controls (Document ID 2307, Attachment 26, Table 2A, URS
Summary Worksheet).
    OSHA disagrees with URS's implicit conclusion that overexposures
are random across facilities. It is not reasonable to assume that
controls have no relation to exposure level as this approach assumes.
As will be discussed later in the context of OSHA's treatment of the
preceding PEL, the data underlying the exposure profile show that
establishments with low exposures are much more likely to have controls
in place than those with very high exposures.
    URS then assumed that if one worker in a job category is
overexposed, then all controls listed by OSHA will be needed (Document
ID 2307, Attachment 25, Engineering Costs). URS did not dispute that
multiple controls would be needed for almost all jobs in general
industry in order reduce exposures from baseline conditions to meeting
the proposed (new) PEL of 50 [mu]g/m\3\. The existence of multiple
controls weakens the theory suggested by URS--that all controls are
needed if even one worker is exposed at levels above the PEL--because
as explained above, some controls are individualized while some protect
groups of workers.
    The best possible approach to what engineering controls are needed
might differ based on whether: (1) There are no controls for a job
category in place at all and most workers are overexposed by a large
margin; or (2) only some workers in a job category are overexposed by a
small margin (i.e., a set of controls is already in place).
    In the first case, the most common approach would be to apply a
relatively full set of controls, as explained in OSHA's technological
feasibility analysis. This might start with enclosures and local
exhaust ventilation (LEV), but, if exposures are high and the
establishment is very dusty, it might also include initial cleaning or
the introduction of ongoing routine housekeeping. In these situations,
in which most employees are overexposed, OSHA estimated that the full
set of controls listed in the technological feasibility analysis would
be applied and, in these cases, there would be little difference in the
results obtained using OSHA's approach and the results obtained using
the approach suggested by URS.
    However, the approach to controlling silica exposures that OSHA
believes to be typical when establishments are faced with the second
situation would be quite different, and therefore different from what
URS expected. Commenters from both labor (Document ID 4204, p. 40) and
industry (Document ID 1992, p. 6) pointed out that when there are
controls in place or only some workers are overexposed, the first step
is to examine work practices. The AFL-CIO noted that exposures can be
controlled through work practices, repositioning ventilation systems,
and controlling fugitive emissions (carryover from adjacent silica
emitting processes) (Document ID 4204, p. 40). Implementing these types
of changes can be inexpensive. The principal cost of improving work
practices may only be training or retraining workers in appropriate
work practices. OSHA's proportional cost approach in the PEA may
therefore overestimate costs for situations in which overexposures can
be corrected with work practice changes because the Agency will have
included costs for engineering controls when, in fact, none will be
needed. The URS approach will always include the costs of all controls
for a job category in any facility where anyone in a job category is
overexposed, and will thus yield even higher estimates.
    As described in Chapter IV, Technological Feasibility, of the FEA,
and summarized below, in situations in which there are LEV systems in
place but the PEL is still not being met, employers would typically try
many things short of removing the entire system and replacing it with a
system with greater air flow velocities (and thus greater capacity and
cost). The incremental solutions to controlling silica exposures
include minor design modification of existing controls, better repair
and maintenance of existing controls, adding additional LEV capacity to
existing systems, improving housekeeping, modifying tools or machinery
causing high levels of emissions, and reducing cross contamination.
    Some worksites might require a slightly different and readily
modified design. For example, an OSHA special emphasis program
inspection of a facility in the Concrete Products industry discovered
that installing a more powerful fan motor, installing a new filter bag
for the bag-filling machine LEV, and moving hoods closer to the packing
operator's position reduced respirable dust exposure by 92 percent, to
11 [mu]g/m\3\ (Document ID 0126, pp. 7-8). In an assessment of the
Asphalt Roofing industry, NIOSH recommended repair and servicing of
existing process enclosures and ventilation systems to eliminate leaks
and poor hood capture but did not indicate that entirely new systems
would need to be installed (Document ID 0889, pp. 12-13; 0891, pp. 3
and 11; 0890, p.14; 0893, p. 12).
    In other cases, better equipment repair and maintenance procedures
can be the key to meeting the PEL when there are already controls in
place. For example, as described in Chapter IV of the FEA, in the
Concrete Products industry, OSHA obtained a sample of 116 [mu]g/m\3\
for a material handler who operated a forklift to transport product
between stations. The inspector noted that there were leaks in the silo
bin chute and that some controls were not fully utilized. The report
indicated that dust generated by various other processes in the
facility was a contributing factor to the forklift operator's high
level of exposure. In this case, the first course of action for the
employer would be to correct the deficiencies in the existing systems.
Similarly, at a site visit in the Paint and Coating industry, ERG
monitored mixer operators' exposures and obtained results below the
limit of detection while workers emptied 50-pound bags of powder into
hoppers when dust control systems were working properly. These values
are 95 percent lower than the 263 [mu]g/m\3\ obtained during another
shift, at the same plant, when the dust control systems malfunctioned
(Document ID 0199, p. 9).
    In other cases, as pointed out by a foundry commenter, adding LEV
capacity to existing systems for silica emissions not yet subject to
any LEV control can be a good strategy for lowering exposures (Document
ID 1992, p. 6). In one foundry, NIOSH investigators recommended
installation of LEV over the coater and press areas, enclosure of the
coating process, and/or repair and servicing of existing process
enclosures and ventilation systems to eliminate leaks and poor hood
capture (Document ID 0889, pp. 12-13; 0891, pp. 3 and 11; 0890, p. 14;
0893, p. 12).
    Various combinations of improved housekeeping, initial cleaning,
and switching to High-Efficiency Particulate Air (HEPA) vacuums can
also help employers meet the PEL. In the Structural Clay industry,
professional cleaning in a brick manufacturing facility removed
``several inches'' of dust from floors, structural surfaces and
equipment (Document ID 1365, pp. 3-19-3-20; 0571). These changes alone
led

to a dramatic decrease in exposures, by as much as 90 percent, to below
50 [mu]g/m\3\, for materials handlers. Similar results were observed
for grinding operators (Document ID 0571). In one NIOSH evaluation,
operators in a grinding area where good housekeeping practices were
being implemented had substantially lower exposures than operators in a
grinding room where the housekeeping practices were poor. The grinding
room referred to as the ``C plant'' had 2 to 3 inches of settled dust
on the floor and had an exposure result of 144 [mu]g/m\3\. Grinding
operators at the grinding room referred to as the ``B plant,'' where
dust had been cleaned up, had substantially lower exposures (24 [mu]g/
m\3\) (Document ID 0235, pp. 6-7).
    Good housekeeping also increases the useful life of equipment. As
discussed in Chapter IV of the FEA, dust clogs machines and reduces
their useful life. As an example, regulating cotton dust was
acknowledged to increase productivity by reducing down time. It also
increased the useful life of looms (Document ID 2256, Attachment 4, p.
11). The Agency predicts that this is likely to be the case with silica
controls as well. Dust being properly captured at the source can also
result in cost savings in housekeeping activities because less dust
needs to be cleaned up when it is captured at the source and not
allowed to spread (Document ID 2256, Attachment 4, p. 11).
    In specific situations, there are a variety of other controls that
may be useful. As discussed in the Technological Feasibility chapter of
the FEA, Simcox et al. (1999) (Document ID 1146) found that Fabricators
in the Cut Stone industry had a mean exposure of 490 [mu]g/m\3\, which
was reduced 88 percent to 60 [mu]g/m\3\ when dry grinding tools used on
granite were replaced or modified to be water-fed. Similar reductions
were found at other facilities when wet grinding, polishing, and
cutting methods were adopted (Document ID 1365, p. 11-20; 1146, p.
579). In the technological feasibility chapter, OSHA examined the work
practices of cut stone splitters and chippers and found that a
combination of wetting the floor at appropriate times, modifying
ventilation directly from the top of the saws, and retrofitting
splitting stations with LEV reduced exposures from a mean of 117 [mu]g/
m\3\ to a mean of 18 [mu]g/m\3\, an 85 percent reduction (Document ID
1365, p. 11-22; 0180).
    Finally, in situations where there is cross contamination,
employers may achieve the PEL for some workers without implementing any
controls specific to that job category. As pointed out by the AFL-CIO,
when this occurs, OSHA's costs may be overestimated (Document ID 4204,
Attachment 1, p. 105).
    These examples show that in many situations, where there are
already controls in place, or where exposures are only slightly above
the PEL, the PEL can be met by a variety of mechanisms short of
installing an entirely new set of controls. Since the record shows
that, frequently, exposures can be controlled without installing new
engineering controls, OSHA's approach of estimating costs based on the
proportion of the workers exposed above the PEL is much more likely to
be accurate than estimates based on URS's suggestion that all controls
are needed whenever one worker is exposed above the PEL.
    The URS facility-based approach would require taking the costs of
newly installing a full set of controls even if only one worker is
exposed above the PEL. This approach assumes that (1) the existing
exposure levels in a given facility have been achieved without the use
of any controls; and (2) existing controls cannot be improved upon for
less than the cost of installing an entirely new system of controls.
These assumptions are unsupported by the URS comments and the nature of
exposure control, as discussed above.
    OSHA, therefore, rejects URS's approach and is maintaining its per-
worker basis for calculating costs for the FEA. Based on the evidence
presented in this section, the Agency concludes that OSHA's
proportional approach of assigning control costs to each worker based
on the cost per worker of a complete set of controls is a better
approach to commonly encountered exposure situations than to assume
that any reading above the PEL triggers the need for a complete set of
controls.
    The AFL-CIO argued that OSHA's proportional approach resulted in an
over-estimation of costs because it involved adding costs for the
exposed occupation wherever there was an overexposure, even when the
overexposure was primarily or solely the result of cross contamination.
The AFL-CIO recommended that OSHA ``identify operations which are
unlikely to [generate] silica emissions, or background and bystander
exposure measurements, and subtract those measured exposure levels from
those operations which do emit silica'' (Document ID 4204, Attachment
1, pp. 31-32). OSHA has routinely included the elimination of cross
contamination as a component of the controls needed for some job
categories. As discussed in Chapter IV of the FEA, OSHA also believes
that other controls will still be needed for many job categories in
which cross contamination is common and as long as these additional
controls are needed, overall costs will not decline as a result of
controlling cross contamination. However, OSHA agrees that there may be
situations in which correcting cross contamination alone would be
sufficient. In this case, the commenter is right that OSHA may
sometimes overestimate costs.
General Methodological Issues--Comments on Costs Associated With
Exposures Over the Preceding PEL
    Many commenters argued that OSHA should have attributed the costs
of reaching the preceding PEL of 100 [mu]g/m\3\ to this standard
(Document ID 2307, Attachment 8b, p. 16; 2195, p. 33; 1819, p. 2; 2375,
Attachment 2, p. 65; 2307, Attachment 1, p. 2; 2379, Attachment 2, p.
9). For example, Stuart Sessions of Environomics, commenting on behalf
of the ACC, stated that of the workers currently exposed over 50 [mu]g/
m\3\, two-thirds are exposed over 100 [mu]g/m\3\, and that OSHA erred
in excluding the costs of reducing those exposures to 100 [mu]g/m\3\
(Document ID 2307, Attachment C, pp. 2-3).
    OSHA's preliminary initial regulatory flexibility analysis (PIRFA)
for the 2003 Small Business Advocacy Review (SBAR) panel included
benefits and costs associated with future compliance with existing
silica requirements on the basis that the rule would help improve
compliance with the existing silica rules (OSHA, 2003a and 2003b)
(Document ID 1685 and 0938, respectively). Upon further consideration,
OSHA determined that a more fair and accurate measure of the benefits
and costs of the proposed rule was to begin the analysis with a
baseline of full compliance with existing requirements; OSHA has
retained this approach for the final rule. The Agency offers three
reasons in support of this approach. First, the obligation to comply
with the preceding silica PEL is independent of OSHA's actions in this
rulemaking. The benefits and costs associated with achieving compliance
with the preceding silica rules are a function of those rules and do
not affect the choice of PEL. The question before the Agency was
whether to adopt new rules, and its analysis focused on the benefits
and costs of those new rules. Second, the Agency's longstanding policy
is to assume 100 percent compliance for purposes of estimating the
costs and benefits of new rules, and to assume less than full
compliance with the existing OSHA rules would be inconsistent with that
policy. Finally, assuming full compliance with the existing rules is in
keeping with standard OSHA practice in

measuring the incremental effects of a new rule against pre-existing
legal obligations. Reliance on costs that assume full compliance with
both the preceding and proposed (new) OSHA rules makes it easier to
compare the two regulatory schemes.
    Some commenters also disagreed with the way OSHA attributed costs
to employers whose workers were being exposed to silica at levels
greater than the preceding PEL of 100 [mu]g/m\3\ (Document ID 3251, p.
2; 3296, p. 2; 3333, p. 2; 3373, p.2; 2503, p.2; 2291, p. 16; 4209, p.
111). These commenters argued that OSHA did not attribute any costs to
reaching 50 [mu]g/m\3\ to employers whose employees were exposed above
100 [mu]g/m\3\. They argued that OSHA instead assumed that the costs
and controls necessary to reach 100 [mu]g/m\3\ would also be sufficient
to reach a level of 50 [mu]g/m\3\, and as discussed above, that OSHA
did not account for those costs because reducing exposures to the
preceding PEL of 100 [mu]g/m\3\ was already required before this
rulemaking. The American Foundry Society (AFS) argued that OSHA reduced
costs by two-thirds ``under the logic that employers must comply with
the current PEL and the proposal does not add any existing obligation''
(Document ID 2379, Appendix 1, p. 10). AFS added that OSHA's
underestimation of costs in this manner was particularly severe because
OSHA used outdated data that showed more employees with exposures over
100 [mu]g/m\3\, whereas more recent data would show fewer employees
with exposures above 100 [mu]g/m\3\ and more with exposures between 50
and 100 [mu]g/m\3\. Had OSHA used this updated data, in AFS's
estimation, the Agency would have identified more employers needing to
install additional engineering controls and thus there would be
additional costs that were not accounted for in the PEA (Document ID
2379, Attachment 3, pp. 9-10). ACC made a similar point, saying that as
a result of OSHA's methodology, ``the exposure reduction costs for the
estimated 81,000 workers now exposed above 100 [mu]g/m\3\ are not taken
into account by OSHA on either a full cost basis or an incremental cost
basis'' (Document ID 2308, Attachment 9, pp. 2-3).
    In addition URS, among others, argued that ``OSHA fails to account
for the non-linear costs associated with each incremental reduction in
silica concentrations,'' meaning that URS believed that it is more
costly to achieve additional reductions in exposure as exposures are
lowered. For example, according to URS's contention, it would be more
costly to reduce exposures from 75 [mu]g/m\3\ to 50 [mu]g/m\3\ than
from 125 [mu]g/m\3\ to 100 [mu]g/m\3\ (Document ID 2308--Attachment 8,
p. 11; 2291, p. 16; 4209, p. 11; 2307, Attachment 2, pp. 181-182; 2379,
Attachment 2, p. 9; 3487, p. 13).
    OSHA has several responses to these criticisms. In response to the
criticism that OSHA overestimated the number of workers with exposure
levels above 100 [mu]g/m\3\ as a result of using outdated data, the
Agency has updated the exposure profile used to develop the final
analysis of costs. This update is described previously in Chapters III
and IV of the FEA. As a result of this update, OSHA found that, in the
aggregate, the percentage of workers in general industry and maritime
exposed to silica levels between 50 [mu]g/m\3\ and 100 [mu]g/m\3\ rose
from 33 percent as estimated in the PEA to 42 percent. And, as the
commenters noted would be the case, the percentage exposed at levels
above 100 [mu]g/m\3\ fell from 67 percent to 58 percent. OSHA has
updated this analysis to incorporate these data and has estimated costs
for these additional workers whose exposures fall between 50 [mu]g/m\3\
and 100 [mu]g/m\3\. The revised distribution also shows that of those
workers with exposures above the new PEL, 41 percent are exposed
between the new PEL and the preceding general industry PEL with an
average exposure level of 70 [mu]g/m\3\, 29 percent are exposed between
the preceding PEL and 250 [mu]g/m\3\ with an average exposure level of
156 [mu]g/m\3\, and 30 percent are exposed above 250 [mu]g/m\3\ with an
average exposure level of 485 [mu]g/m\3\. Where an industry submitted
more recent exposure data or information about exposure distributions
within their industry, OSHA was able to show that its final exposure
distribution was roughly equivalent (see Chapter IV of the FEA).
    The technological feasibility analysis (presented in Chapter IV of
the FEA) describes the controls necessary for reducing exposures from
the highest levels observed in an industry's exposure profile to the
new PEL. In all application groups except two (asphalt paving products
and dental laboratories), the highest observed exposures were above the
preceding PEL. With the exception of hydraulic fracturing,\28\ the
technological feasibility analysis did not distinguish between the
controls necessary to meet the preceding general industry PEL of 100
[mu]g/m\3\ and those necessary to meet the new general industry PEL of
50 [mu]g/m\3\. Instead, the technological feasibility analysis simply
listed the controls necessary for those employers whose employees had
the highest baseline exposures to significantly reduce exposures and,
in most operations, meet the new PEL.
---------------------------------------------------------------------------

    \28\ Due to an unusually rich data set, and the great similarity
of different fracturing operations, both with respect to the
equipment used and the current levels of control, OSHA was able to
estimate which controls are necessary to go from an uncontrolled
situation to the preceding PEL and which are necessary to get from
the preceding PEL to the new PEL in the hydraulic fracturing
industry.
---------------------------------------------------------------------------

    It was not necessary for OSHA to distinguish between controls
necessary to achieve the preceding PEL and those necessary to achieve
the new PEL in order to demonstrate the technological feasibility of
achieving a PEL of 50 [mu]g/m\3\. Such a distinction would have been
difficult because, from a baseline of uncontrolled exposures, the
controls necessary to meet the preceding and new PELs are difficult to
distinguish. For example, if there are two different controls necessary
to fully meet the new PEL, then it is logically possible that two
different establishments may achieve an exposure level at or below the
preceding PEL in different ways. One establishment may have excellent
housekeeping but poorly maintained LEV. Another may have well
maintained LEV but poor housekeeping. For individual cases, there is
not a simple demarcation of which controls of the total set of controls
are necessary to achieve the new PEL when only the exposure level and
not the controls already in place are known. Nor, as discussed above,
is it the case that a control, once installed, will always provide
identical protection. Two otherwise equal facilities may have the same
installed controls but different exposure levels because of the quality
of the maintenance of the system.
    For the purposes of costing engineering controls for general
industry and maritime in the PEA, OSHA assigned all of the costs for
meeting a PEL of 50 [mu]g/m\3\--including the costs of controls
necessary to meet the preceding PEL of 100 [mu]g/m\3\--to all workers
with exposure levels between 50 [mu]g/m\3\ and 100 [mu]g/m\3\. However,
OSHA assigned no costs in the PEA to employees whose exposures exceeded
the preceding PEL. This approach would be accurate for both those above
and below the preceding PEL only if the exact same controls would be
needed to control exposures in both situations and these controls would
always yield an exposure level below the preceding PEL. However, as
discussed in the previous section on proportionality of costs, OSHA has
determined that this is not typically the case. There exist multiple
kinds of controls and the actual application and operation of the
control can differ. The approach applied in the PEA applied more
controls than will typically be needed where exposures are below the
preceding PEL and thus overestimates costs in these situations, but
then assigns no costs for achieving

the new PEL where exposures are above the preceding PEL. In the latter
situation, it can reasonably be expected that, in most cases, some
costs would be incurred to meet the new PEL even after the preceding
PEL is met and therefore the PEA methodology underestimated costs in
those situations. Although these over- and under-estimates are
partially offsetting, OSHA acknowledges that any over-estimates of cost
do not necessarily offset the potential under-estimates of costs.
    OSHA has therefore decided to adopt an approach to the estimation
of costs different from that adopted in the PEA. In the FEA, OSHA
relied on data available in the rulemaking record to both correct the
overestimate of costs for those below the preceding PEL and, as many
industry commenters urged, estimate the costs necessary to meet the
preceding PEL as well as the new PEL for those above the preceding PEL.
    To be clear, these data still do not enable OSHA to distinguish
between the exact controls needed to get from uncontrolled exposures to
the preceding PEL and those needed to get from the preceding PEL to the
new PEL on an industry-by-industry and occupation-by-occupation basis.
However, the data do enable OSHA to show that the majority of the costs
of controlling silica exposures are incurred in order to reduce
exposures from uncontrolled levels to the preceding PEL. OSHA will then
assume that 50 percent of the costs incurred will be to implement the
controls necessary to get from the uncontrolled situation to the
preceding PEL and 50 percent to implement the controls necessary to go
from the preceding PEL to meeting the new PEL. If, in fact, a majority
of the costs are incurred in order to reduce exposures to the preceding
PEL, the assumption that attributes 50 percent of costs to going from
the preceding PEL to the new PEL will overestimate the true costs for
establishments with exposures at the preceding PEL or between the
preceding PEL and the new PEL.
    In order to assess whether the majority of the costs are necessary
to meet the preceding PEL, OSHA first examined what kinds of exposures
are associated with the uncontrolled situations that served as the
starting point for the estimates of needed controls in the
technological feasibility analysis. The average level of exposure
across all of general industry for employees with exposure exceeding
the preceding PEL is over 300 [mu]g/m\3\. Thus, on average, across all
industries the uncontrolled situation involves high levels of exposure,
commonly more than 3 times the preceding PEL.\29\
---------------------------------------------------------------------------

    \29\ To check that this was not the result of a very high
exposures for a small number of employees or industries, OSHA
examined the exposure profile presented in Table III-9 and found
that in only 4 industries (with 1.1 percent of all employees exposed
above the preceding PEL) were there no exposures above 250 [mu]g/
m\3\.
---------------------------------------------------------------------------

    In general, to reduce exposures from over 2.5 times the preceding
PEL to the preceding PEL, employers would have to implement some
measure or measures, and those measures would be the ones that provide
the greatest reduction in silica exposures and therefore control most
of the silica exposures in the facility. In most cases this will be a
working LEV system or some form of worker isolation. Measures like
improved housekeeping cannot reduce exposures from the levels observed
in uncontrolled exposure situations to the preceding PEL. OSHA reviewed
industry-by-industry and occupation-by-occupation cost estimates for
engineering controls and found that, on average 63 percent of the costs
were for LEV, 23 percent were for housekeeping, and 16 percent were for
other controls, most commonly wet methods (based on OSHA, 2016). In
many cases, where wet methods were applicable, wet methods represented
the majority of the costs and there were not significant LEV costs. As
a result, 79 percent of the costs of controls, on average, are
attributable to either wet methods or LEV. The combination of LEV or
wet methods with some improvement in housekeeping (though not the
improvements necessary to meet the new PEL) will constitute the
majority of costs for virtually all occupational categories. Some
improvement in housekeeping will typically also be required to meet
even the preceding PEL.\30\ While employers can probably meet the
preceding PEL with less than ideally maintained LEV systems,
improvements in maintenance will not reverse the conclusion that the
majority of the costs are incurred to meet the preceding PEL. This is
the case because on average 63 percent of engineering control costs are
necessary to reach the preceding PEL and some housekeeping costs will
also be necessary, leaving a significant percentage of expenditures
above 50 percent of the costs available for improved maintenance.
---------------------------------------------------------------------------

    \30\ For example, in several industry sectors where workers are
currently manually dumping silica-containing materials, the use of
automated and ventilated dumping stations is needed to reduce
exposures from over 250 [mu]g/m\3\ to below the preceding PEL.
However, once these controls are installed and in use, final
exposures are often below the limit of detection or less than 12
[mu]g/m\3\--well below the new PEL (see technological feasibility
chapter for paint and coatings). However, to maintain these
exposures below the new PEL, these industry sectors will need to
ensure that ventilation systems are properly maintained and will
need sufficient housekeeping to ensure against build-ups of dust.
---------------------------------------------------------------------------

    To confirm the findings of this cost-spreadsheet-based analysis of
where the majority of the costs are incurred, OSHA reviewed industries
where good data are available on controls in both uncontrolled
situations and situations with exposures between the new and the
preceding PEL. OSHA examined the exposures and controls in eight
ferrous sand casting foundry facilities. In these eight facilities,
four had relatively few workers exposed above 50 [mu]g/m\3\, and the
other 4 had many exposures over 100 [mu]g/m\3\. OSHA found that those
facilities with most exposures over 100 [mu]g/m\3\ generally had little
or no LEV (relying instead on general ventilation), poor housekeeping,
no enclosures for workers, and poor maintenance. The foundries where
silica dust was better controlled generally had working LEV systems,
good housekeeping that kept surfaces free of silica dust, and good
maintenance practices. This indicates that LEV and some housekeeping
are essential to meeting the preceding PEL. OSHA also examined data on
all exposures with control descriptions. These data showed that
exposures above 250 [mu]g/m\3\ occurred in uncontrolled situations or
situations in which controls, though installed, were not in use. In
situations where exposures were between the preceding and new PELs,
most exposures showed some controls in place, normally LEV, but not all
controls recommended. In some cases there were no controls in place.
These generally represented situations in which exposures were much
lower than the typical uncontrolled situations and such facilities
would not normally need the full controls necessary to go from very
high levels of exposure to the new PEL (See Exhibit: Descriptions of
Control, available in Docket OSHA-2010-0034 at www.regulations.gov).
    Based on these findings, OSHA determined that the majority of costs
are incurred in order to implement controls necessary to get from an
uncontrolled situation to the preceding PEL. However, OSHA developed
cost estimates for engineering controls based on the conservative
assumption that 50 percent of the total costs of going from an
uncontrolled situation to the new PEL is incurred in order to reach the
preceding PEL and the remaining 50 percent are incurred to reach the
new

PEL.\31\ For example, in the cut stone industry 63 percent of those
exposed above the new PEL are also above the preceding PEL and 37
percent are below the preceding PEL but above the new PEL. The total
cost to the cut stone industry of going from uncontrolled exposure to
the new PEL is $17.7 million. With OSHA's assumption that half of the
costs of going from an uncontrolled situation to the new PEL is
incurred in order to reach the preceding PEL, then the cost for those
employers with employees exposed above the preceding PEL would be 63
percent of $17.5 million times 0.5, which equals $5.5 million. The cost
for those below the preceding PEL would be 37 percent of $17.7 million
times 0.5, which equal $3.3 million. The total cost of going from the
preceding PEL to the new PEL in the cut stone industry is therefore the
sum of these two calculations: $8.8 million. This will overestimate the
costs of reaching the new PEL, given the majority of the costs are
incurred to implement controls necessary to reach the preceding
PEL.\32\
---------------------------------------------------------------------------

    \31\ This approach was not applied to the two industries, dental
laboratories and asphalt paving materials, where the exposure
profile showed that there were no exposures above the preceding PEL.
    \32\ OSHA also notes that this approach shows rising incremental
costs of control, which is consistent with some comments. This is
because 50 percent of the costs are estimated to be incurred to go
from levels of over 250 [mu]g/m\3\ to 100 [mu]g/m\3\ and equal costs
are estimated to be incurred to go from 100 [mu]g/m\3\ to 50 [mu]g/
m\3\.
---------------------------------------------------------------------------

    As presented in more detail below, this approach results in a total
annualized cost estimate for general industry and maritime engineering
controls of $225 million. Fortunately, this cost estimate is not highly
sensitive to the allocation percentage chosen. Each decrement of 5
percentage points changes the engineering control costs by
approximately 5.5 percent. Thus, for example, if 65 percent of the
costs are necessary to go from the preceding PEL to the new PEL, then
the annualized cost estimate for engineering controls would rise to
$261 million per year.\33\
---------------------------------------------------------------------------

    \33\ A value of 100 percent would be totally implausible as it
would imply that all establishments currently far above the
preceding PEL could achieve that PEL without cost. Put another way,
this would be equivalent to saying that, if OSHA had decided to
adopt the alternative PEL of 100 [mu]g/m\3\ (i.e., the same as the
preceding general industry PEL), as some employer groups
recommended, any employers currently above that PEL--regardless of
how far above the PEL they were--would be able to meet a PEL of 100
[mu]g/m\3\ without implementing any new engineering controls.
---------------------------------------------------------------------------

Accounting for Costs of Downtime
    Some commenters suggested that OSHA failed to account for the
downtime that installing engineering controls or performing an initial
through cleaning would require (e.g., Document ID 2368, p. 13 for
engineering controls; Document ID 2379, Attachment 2, p. 16 for initial
thorough cleaning).
    Almost all firms need downtime occasionally in order to perform
general maintenance, inventory, or other tasks. In the final rule, OSHA
has extended the compliance date for general industry from one year to
two years. This will allow almost all employers to schedule work that
might require downtime to install, improve, or maintain controls that
they determine are necessary to meet the new PEL or to perform the
initial thorough cleaning at times when they would already need
scheduled downtime for other purposes. Therefore, OSHA has determined
that there will be no additional costs incurred for downtime in order
for employers to install engineering controls or to perform the initial
thorough cleaning.
Technological Change
    One commenter, Dr. Ruth Ruttenberg, testifying for the AFL-CIO,
argued that OSHA had overestimated costs by failing to consider
technological change:

    Technological improvements--both engineering and scientific--are
constantly occurring, especially when the pressure of a pending or
existing regulation provide a strong incentive to find a way to
comply at a lower cost. . . . These improvements are well-documented
following the promulgation of rules for vinyl chloride, coke ovens,
lead, asbestos, lock-out/tag-out, ethylene oxide, and a host of
others (Document ID 2256, Attachment 4, p. 2).

    Dr. Ruttenberg recognized that OSHA, in the PEA, already predicted
some ``technological and cost-saving advances with silica,'' such as
expanding the use of automated processes and developing more effective
bag seals, but criticized OSHA for not accounting for those cost
savings in its analysis:

    Technological improvements are as sure a reality--based on past
experience and academic research--as overestimation of cost and
underestimate of benefits are in an OSHA regulatory analysis. More
than 40 years of OSHA history bear this out (Document ID 2256,
Attachment 4, p. 3).

    When promulgating health standards, OSHA generally takes an
approach in which cost estimates and economic feasibility analyses are
based on the technologies specified in the technological feasibility
analysis. This is a conservative approach to satisfying OSHA's legal
obligations to show economic and technological feasibility. As a
result, the Agency does not account for some factors that may reduce
costs, such as technological changes that reduce the costs of controls
over time and improvements in production that reduce the number of
employees exposed. As pointed out in the PEA, and from the examples
described in the ``Total Cost Summary'' at the end of this chapter,
some past experience suggests that these factors tend to result in
OSHA's costs being overestimated.\34\ OSHA considers the primary
purpose of the cost estimate to be to provide a basis for evaluating
the economic feasibility of the rule, and OSHA has determined that for
this rulemaking, feasibility is most accurately demonstrated by using
an approach that does not account for the potential impacts of future
technological changes.
---------------------------------------------------------------------------

    \34\ On the other hand, there is supplemental evidence from
Harrington et al. (2000) [Harrington, Winston, Richard D.
Morgenstern and Peter Nelson. ``On the Accuracy of Regulatory Cost
Estimates.'' Journal of Policy Analysis and Management, 19(2), 297-
322, 2000] that OSHA does not systematically overestimate costs on a
per-unit basis, and that the reason for overestimation of costs at
the aggregate level has been a combination of difficulty with
establishing baseline conditions and noncompliance. Nevertheless,
several examples of OSHA's overestimation of costs reported in the
article are due to technological improvements.
---------------------------------------------------------------------------

General Methodological Issues: Number of Workers Covered by a Control
PEA Estimates
    The cost calculations in the PEA included estimates of the number
of workers whose exposures are controlled by each engineering control.
Because working arrangements vary within occupations and across
facilities of different sizes, there are no definitive data on how many
workers are likely to be covered by a given set of controls. In many
small facilities, especially those that might operate only one shift
per day, some controls will limit exposures for only a single worker.
Also, small facilities might have only one worker in certain affected
job categories. More commonly, however, and especially in the principal
production operations, several workers are likely to derive exposure
reductions from each engineering control.
    The PEA relied on case-specific judgments of the number of workers
whose exposures are controlled by each engineering control (see Table
3-3 in ERG, 2007b, Document ID 1608). The majority of controls were
estimated to benefit four workers, based on the judgment that there is
often multi-shift work and that many work stations are shared by at
least two workers per shift. The costs of some types of equipment that
protect multiple employees, such as HEPA vacuums, were spread over
larger groups of employees (e.g., six to eight workers). In the PEA,
the average number of workers affected represented

an average across all establishments, large and small.
Comments and Responses
    Some commenters questioned OSHA's estimate of the number of workers
whose exposures could be controlled per newly added or enhanced
control. OSHA's PEA most commonly estimated that four workers would
have their exposures reduced for each new or enhanced engineering
control. Dr. Ronald Bird, testifying for the Chamber of Commerce,
argued that OSHA's estimates were simply arbitrary assumptions
(Document ID 2368, p. 14). Stuart Sessions, testifying for the ACC,
argued that the use of a single standard crew size of four led OSHA to
underestimate costs and economic impacts for smaller establishments, at
which, he argued, ``there are virtually never as many as four
overexposed workers in any job category, and it is simply impossible
that one application of a package of controls in this situation could
protect as many as 4 overexposed workers on average'' (Document ID
4231, Attachment 1, p. 6).
    The approach OSHA used was intended to represent the average number
of employees affected by a given set of controls. Larger establishments
may have more than four workers whose exposures are reduced by a single
control, and smaller establishments may have fewer than four. However,
OSHA agrees that this approach may result in an underestimate of costs
for the smallest establishments. Because it is particularly important
to consider the costs to the smallest establishments, OSHA has reduced
the number of employees whose exposures are reduced per control by half
for establishments with fewer than twenty employees, so that in those
small establishments a given control is assumed to reduce exposures for
two workers instead of four as assumed in the PEA. Because larger
establishments may have greater numbers of employees whose exposures
are reduced per control, this change may result in an overall
overestimation of costs. (In the PEA, the overestimation of costs for
larger facilities was partially offset by the underestimation of costs
for smaller establishments. This is no longer the case in the FEA.)
OSHA nevertheless believes the revised approach used in the FEA is
better than the approach used in the PEA for purposes of capturing
economic impacts on smaller establishments, even though it may result
in aggregate costs being overestimated.
Variability
    Some commenters argued that both OSHA's technological feasibility
and cost analyses were flawed because OSHA neglected to address the
day-to-day variability of exposure measurements. By failing to address
the issue of variability, these commenters argued, OSHA grossly
underestimated the costs of engineering controls. These commenters
reported that silica exposures would have to be controlled to levels
considerably lower than the proposed (new) PEL in order to account for
the variation in exposures across jobs and from day to day (e.g.,
Document ID 2307, Attachment 2, p. 202; 2308, Attachment 7, p. 2; 2308,
Attachment 8, p. 6; 2379, Attachment 4, p. 1; 2291, p. 11; 2195, pp.
26-27; 2503, p. 2; 2222, Attachment 1, p. 1). For example, in response
to a written question about the activities in which employers were able
to achieve the proposed (new) PEL ``most of the time,'' AFS objected to
the premise of the question, noting that ``[s]everal foundries have
received citations for exposures above the current PEL on operations or
tasks for which the proposed PEL is achieved most of the time''
(Document ID 2379, Appendix 1, p. 18). AFS argued that OSHA's non-
compliance model of enforcement requires employers to reduce average
exposures to half the PEL in order to have confidence that exposures
will never exceed the PEL (Document ID 2379, Appendix 2, p. 29). The
Asphalt Roofing Manufacturing Association (ARMA) made a similar point
and said that the majority of asphalt roofing plants operated by its
members have some exposures over the PEL of 50 [mu]g/m\3\, even if it's
a ``relatively small incidence'' (Document ID 2291, p. 11).
    Both AFS and ARMA offered estimates of the magnitude of this
variability by measuring the statistical variance of exposures. AFS
stated that to assure 84 percent confidence in compliance with the
preceding PEL, the mean exposures in some specific jobs in specific
foundries would need to be below half that PEL, and that the ``mean
level necessary to achieve the 95 percent confidence of compliance
could not be determined but is significantly below one half the PEL''
(Document ID 2379, Appendix 1, p. 23).
    ARMA examined the distribution of silica exposures in over 1,300
samples from 57 asphalt roofing facilities. These data showed that even
though the median exposures for all jobs were below the new action
level of 25 [mu]g/m\3\, a total of 9 percent of all samples were above
the new PEL of 50 [mu]g/m\3\ (Document ID 2291, p. 5, Table 1). ARMA
also provided an estimate of the ``lowest strictly achievable level''
(meaning a level not to be exceeded more than 5 percent of the time)
which varied by job classification from 67 to 310 [mu]g/m\3\ (Document
ID 2291, p. 9, Table 2).
    One serious problem with the ARMA analysis is that the discussions
of variability and the estimates of mathematical variance are based on
results either from different facilities with potentially different
levels of controls or from all job categories within one facility. The
key issue for assessing the importance of variability is the variance
within a given job category in a specific establishment with specific
controls. The methodology employed is such that even if individual job
categories or individual facilities had no variance, pooling data
across facilities would create variance.
    ARMA estimated that sufficiently controlling variation would
require investment in capture vents, duct work, and dust collection
systems costing up to $2.1 million each in initial costs per
manufacturing line (Document ID 2291, p. 12). AFS did not provide a
cost estimate solely for sufficiently controlling variation.
    The AFL-CIO disagreed with industry's arguments and instead argued
that the best way to reduce variability was not simply to add
additional engineering controls because, as explained earlier in the
discussion of URS's comments on the per-worker cost basis,
overexposures are not random:

    The worker-to-worker variation is explainable and controllable:
Workers use different methods, they may take different positions
relative to ventilation systems, they may use different work
practices, and they may be subject to fugitive emissions (carryover
from adjacent silica emitting processes). These differences in
conditions can be observed by the industrial hygienist collecting
the air sample, compared to exposure levels, and changed. Day-to-day
variation for the same worker is caused by variation in materials,
ventilation systems, production rate, and adjacent sources showing
such variation. Sometimes these variations can be large, based on
breakdowns of ventilation, process upsets and blowouts (Document ID
4204, p. 40).

    OSHA's enforcement policies are discussed in Chapter IV of the FEA
and in this preamble. Variability of exposures is potentially a cost
issue when there are technologically feasible controls that have costs
not otherwise accounted for that could further reduce environmental
variability. If it is not technologically feasible to reduce
variability then there will be no further costs. For example, if an
employer has

installed all feasible controls, there are no additional costs for
engineering controls because there are no additional controls to
purchase, regardless of variability. On the other hand, an employer who
has a median exposure level of 80 percent of the PEL with frequent
excursions above and who could feasibly reduce variability would be
required to do so.
    As noted above, those (AFS, ARMA) who argued that OSHA had
underestimated costs by failing to account for exposure variability, in
general, assumed that the best approach to reducing variability would
be to increase the levels of LEV to reduce the average exposure level
to half of the PEL or less, without examining the origin of the
variability.
    OSHA agrees with the AFL-CIO that variability in exposure is likely
controllable by examining the origins of the variability. One origin is
poor work practices. To improve work practices, employers could observe
work practices when monitoring takes place; determine which work
practices are associated with high exposures; and modify those work
practices found to lead to high exposures. Variability can also be the
result of a failure of controls not functioning properly, either
resulting from sudden failures or from gradual deterioration of
performance over time. The latter can be prevented by good maintenance.
    Both in its cost assessment for the proposal and in the
modifications made for this final rule, OSHA has taken account of the
costs necessary to reduce unusual and exceptionally high exposure
levels and thus reduce some sources of variation. As discussed in the
cost of ancillary provisions, OSHA has estimated costs for exposure
monitoring that include the time for observation of the worker. OSHA
has also estimated costs for training to assure good work practices,
and has increased the estimated length of training in general industry
to ensure that the time is sufficient for training on work practices.
In this section, OSHA has costed LEV, LEV maintenance, and the need for
replacement LEV to assure that the LEV will function properly. OSHA has
therefore already accounted for a variety of costs associated with
steps that can be taken to reduce variability in exposures.
Substitution of Low- or Non-Silica Inputs
PEA Estimate
    For several industries, employers might lower silica exposures by
substituting low- or non-silica inputs for existing inputs. While this
option can be an extremely effective method for controlling silica
exposures in many industries, OSHA did not cost this option in the PEA.
OSHA determined that there were often complicating factors that
restricted the potential for broad substitution of non-silica-
containing inputs for silica-containing inputs throughout the affected
industries. It is possible that the same product quality cannot be
maintained without using silica. Some products made with substitute
ingredients were judged to be inferior in quality and potentially not
viable in the market. In addition, a substitute silica ingredient might
introduce adverse health risks of its own. Further, in several
instances, the availability of reasonably inexpensive alternative non-
silica ingredients was well known but the alternative was not selected
as a control option by most firms. In light of these concerns, OSHA
decided not to include the option of non-silica substitutes in
estimating the cost of the proposed rule.
Comments and Responses on Substitution
    Some commenters complained that OSHA's analysis did not account for
the costs of substitution (Document ID 2264, Attachment 1, p. 27; 2379,
Attachment 2, p. 6; 3485, p. 25; 3487, p. 17).
    OSHA considered the comments on the issue but has decided to adhere
to the approach taken in the PEA. OSHA did not take account of the
costs of substituting other substances for silica, because, while such
substitution might have substantial benefits and avoid the need for
engineering controls, OSHA determined that, in most situations,
substitution is not the least costly method of achieving the proposed
or new PEL (Document ID 2379, Attachment 2, p. 6). As a result, OSHA's
final cost analyses do not account for the possibility that firms would
choose to substitute for substances other than silica. To the extent
that substitutes are the least costly solution in some situations, OSHA
has overestimated the costs.
Cost of Air Quality Permit Notification
    The Agency received comments suggesting that foundries and other
manufacturing plants would be required by the Environmental Protection
Agency (EPA), or other federal or state environmental authorities, to
incur an administrative cost to ensure their systems are compliant with
relevant EPA regulations. Commenters expressed concern that the
permitting process itself could be a major undertaking, made worse by
difficult compliance deadlines. Given that the final rule provides
extra time for planning and permitting, OSHA has examined the potential
impacts of the new rule and finds that the commenters are overstating
the potential for such costs. The argument for significant permitting
costs was typically combined (e.g., Document ID 2379, Appendix 3) with
an argument that the Agency underestimated the amount of ventilation
required to comply with the final rule; comments on ventilation
requirements are dealt with in great detail elsewhere in this chapter.
    Upon investigation, while OSHA agrees that it would be appropriate
to recognize an administrative burden with respect to the interfacing
environmental regulations, the Agency believes that many of the
commenters' concerns were overstated. First, many control methods
needed to comply with the final rule will not require alterations to
existing ventilation systems. As discussed earlier in Chapter V of the
FEA, work practices, housekeeping and maintenance are important
components in controlling exposures; in many cases existing
ventilation, as designed and permitted with the environmental
authority, is adequate, but needs to be maintained better. In addition,
most establishments, particularly smaller ones, will continue to have
particulate emissions levels that fall below the level of EPA permit
requirements. In the case of large facilities that do not, the changes
will be on a sufficiently small scale that they will not require
elaborate repermitting, but will only require minor incremental costs
for notifying the environmental authorities, or in some cases,
submitting a ``minor'' permit (see http://www2.epa.gov/nsr and http://www2.epa.gov/title-v-operating-permits). Taking into account the
preceding silica PEL and the estimate that baghouses will capture 99
percent of silica emissions (Document ID 3641, p. VII-19), OSHA
concludes that it is unlikely that facilities will encounter a need for
significant air permit modifications.
    The Agency recognizes, however, that there will be minor
incremental costs for notifying environmental authorities. While many
establishments in the United States may have no requirement to do so,
the Agency has conservatively assumed that all establishments with
twenty or more employees in most industries will need to dedicate a
certain amount of time to preparing a one-time notification to
environmental authorities to ensure that their air permits accurately
reflect current operating conditions. OSHA has determined that small
establishments

would generally lack the large scale industrial facilities requiring
permits, and that the few that might require such permits would be
balanced out by the likely inclusion of medium establishments that do
not actually require permits for their emissions. The industries
excluded were those that generally lack large scale industrial
facilities, or that do not produce a concentrated, as opposed to
diverse or unconsolidated, emission source. The excluded industries
were hydraulic fracturing, shipyards, dental equipment and labs,
jewelry, railroads, and landscaping.
    To allow for adequate administrative time for creating and
submitting the notification, at those facilities that could potentially
incur costs, OSHA allocated 20 hours to establishments with 20 to 499
employees and 40 hours to establishments with 500 or more employees. A
manager's loaded hourly wage rate of $74.97 was applied to estimate the
cost to employers (BLS, OES, 2012, Document ID 1560). The costs per
establishment were estimated at approximately $1,500 per medium
establishment and $3,000 per large establishment. Because both new
permit applications and permit modifications are minor administrative
chores, OSHA's cost estimates are sufficient to cover either case.
Costs for Specific Engineering Controls
Ventilation Costs
PEA Estimates
    In the PEA, OSHA determined that at many workstations, employers
needed to improve ventilation to reduce silica exposures. The cost of
ventilation enhancements estimated in the PEA generally reflected the
expense of ductwork and other equipment for the immediate workstation
or individual location and, potentially, the cost of incremental
capacity system-wide enhancements and increased operating costs for the
heating, ventilation, and air conditioning (HVAC) system for the
facility.
    In considering the specific ventilation enhancements for given job
categories the PEA estimated the type of LEV and the approximate
quantity in cubic feet per minute (cfm) of air flow required to reduce
worker exposures.
    To develop generally applicable ventilation cost estimates for the
PEA, a set of workstation-specific and facility-wide ventilation
estimates were defined using suggested ventilation approaches described
in the American Conference of Governmental Industrial Hygienists
(ACGIH) Industrial Ventilation Manual, 24th edition (Document ID 1607).
With the assistance of industrial hygienists and plant ventilation
engineering specialists, workstation estimates of cfm were derived from
the ACGIH Ventilation Manual, and where not covered in that source,
from expert judgements for the purpose of costing LEV enhancements
(Document ID 1608, p. 29).
    Over a wide range of circumstances, ventilation enhancement costs,
which included a cost factor for HEPA filters and baghouses, where
needed, varied from roughly $9 per cfm to approximately $18 per cfm
(Document ID 1608, p. 29). Because of a lack of detailed data to
estimate the specific ventilation installation costs for a given
facility, an estimate of the likely average capital cost per cfm was
used and applied to all ventilation enhancements. Based on discussions
with ventilation specialists, $12.83 per cfm was judged to be a
reasonable overall estimate of the likely capital costs of ventilation
enhancements (Document ID 3983, p. 1).
    OSHA applied the per-cfm capital cost estimate to estimated cfm
requirements for each workstation. By using the unit value of $12.83
per cfm, the cost estimates for each ventilation enhancement included
both the cost of the LEV enhancement at the workstation and the
contribution of the enhancement to the overall facility ventilation
system requirements. That is, each ventilation enhancement at a
workstation was expected to generate costs to the building's general
ventilation system either by requiring increased capacity to make up
for the air removed by the LEV system or to filter the air before
returning it to the workplace.
    For operating costs, engineering consultants analyzed the costs of
heating and cooling system operation for 12 geographically (and
therefore, climatologically) diverse U.S. cities. The analysis,
presented in Table 3-2 in the ERG report (Document ID 1608, p. 30),
showed the heating and cooling British Thermal Unit (BTU) requirements
for 60-hours-a-week operation (12 hours a day, Monday through Friday)
or for a continuous 24-hour-a-day, year-round operation, with and
without recirculation of plant air. Facilities that recirculate air
have much lower ventilation system operating costs because they do not
need to heat or cool outside air to comfortable inside temperatures.
    In the PEA, ventilation operating costs were based on a weighted
average of the costs of four operating scenarios: (1) No recirculated
air, continuous operation; (2) no recirculated air, operating 60 hours
per week; (3) recirculated HEPA filtered air, continuous operation; and
(4) recirculated HEPA filtered air, operating 60 hours per week. These
scenarios were chosen to reflect the various types of operating system
characteristics likely to be found among affected facilities. The
weights (representing the share of total facilities falling into each
category) and operating costs per cfm for each of these scenarios are
shown below in Table VII-11-1:

[GRAPHIC] [TIFF OMITTED] TR25MR16.051

    The national average annual operating cost per cfm was estimated to
be $2.22. This estimate was a weighted average of the operating costs
for facilities that recirculate air and those that require make-up air.
The operating costs for HEPA-filter recirculated air were estimated at
$0.50 per cfm for facilities operating 60 hours per week and $1.40 per
cfm for those continuously operating 24 hours per day. The operating
costs for facilities that do not recirculate air were $5.78 per cfm for
those operating 60 hours per week and $15.55 per cfm for those
operating continuously. In generating these estimates, it was judged
that 80 percent of facilities would recirculate airflow and 20 percent
would not, and that 75 percent within each group operate for 12 hours
per day on weekdays, with the remainder operating continuously, year-
round, for 24 hours a day.
    OSHA also added a maintenance factor to the operating cost
estimates, which was 10 percent of the capital cost investments of
$12.83 per cfm for ventilation systems. As a result, the total annual
costs per cfm, excluding annualized capital costs, were estimated to be
$3.50 (weighted average operating costs of $2.22 plus annual
maintenance costs of 10 percent of $12.83).
    Underlying the cost results was the assumption that, over the
course of the proposed one-year compliance period for engineering
controls, employers would schedule installation of ventilation to
minimize disruption of production, just as they would with any
modification to their plants.
Comments and Responses on Local Exhaust Ventilation Issues: Need for a
Complete New System
    Local exhaust ventilation represents one of the major costs
associated with engineering controls in both the PEA and in the FEA.
Commenters raised issues both about OSHA's PEA estimates of the unit
costs of LEV and about the adequacy of OSHA's estimates of the volume
of LEV that would be needed to adequately control silica exposures.
    URS, testifying on behalf of ACC, argued that any firm that would
be utilizing LEV to meet a PEL of 50 [mu]g/m\3\ would need to remove
any existing LEV and install an entirely new LEV system. Thus, in URS's
estimation, there would be no incremental addition of LEV. In a
discussion of the URS approach during OSHA's informal public hearings,
OSHA asked the URS representative to confirm that his organization
commented that when a majority of workers are exposed over the PEL, the
existing controls must be replaced instead of enhanced:

    MR. BURT: I want to be sure I understand what that's saying.
Let's say you encountered a situation in which there were four
workers. Two were exposed at 35, two at 60. You would scrap all of
the controls and start over again. That's what it seems to be
saying.
    [. . .]
    MR. WAGGENER: [Y]es, that they would need to be replaced with a
more adequate system (Document ID 3582, Tr. 2109-2110).

    OSHA's examination of the spreadsheets URS provided documenting its
independently developed cost estimates shows that, in all cases where
any employee in an establishment was exposed above 50 [mu]g/m\3\, URS
assumed that the employer would need to install a complete new LEV
system and included the costs for installing and operating this
entirely new system (Document ID 2308, Attachment 8, pp. 13-14).
    John Burke from OSCO Industries took a different approach to the
question that better illustrates the options that OSHA believed to be
available when it developed the PEA estimates:

    A single large dust collector is probably already handling the
exhausting of the entire sand conditioning system. Most likely all
the pick-up points referenced in the economic analysis already have
suction being applied and yet there is still an overexposure. What
do you do and how much is that going to cost? If the sand system
operator is overexposed then you could first evaluate work practices
controls. If work practice controls are unsuccessful and additional
suction is needed, that suction is going to be very expensive! If
your environmental operating permit allows it you may be able to
tweak the performance of the dust collector. There may be some
things you can

do to tweak the capacity of your existing dust collector to bring it
up to exactly its permitted air volume or you might have to enlarge
your dust collector (Document ID 1992, p. 6).

    OSHA agrees with Mr. Burke. As discussed above, there are usually a
wide variety of ways to improve existing controls before removing and
reinstalling an LEV system. As a result, OSHA finds the URS approach
unrealistic and likely to significantly overestimate costs.
Comments and Responses on the Volume of Controls Needed
    One commenter, URS, questioned OSHA's estimates of the volume of
additional LEV that would be needed to comply with the standard. URS,
testifying for ACC, reported that OSHA's estimates in the PEA were too
low as compared to the recommendations in Table 6-2 of the ACGIH
Ventilation Manual (28th Edition). They criticized OSHA's estimates
saying that OSHA routinely underestimated required capture velocities
by at least a factor of two for particles with high (conveyor loading,
crushing) or very high (grinding, abrasive blasting, tumbling) energies
of dispersion (Document ID 2308, Attachment 8, pp. 12 and 14). URS said
that ``the capture velocities for LEV systems in OSHA's models were
often based on the minimum recommended velocity,'' that OSHA's
estimated additional LEV was too low because ``the ACGIH capture
velocity values used by OSHA were first developed and published many
years ago'' and were not sufficient to control dust to the levels OSHA
is now proposing, and that ``the velocity values used in OSHA's cost
model are most likely undersized by a factor of 2 or more'' (Document
ID 2308, pp. 11-12). Other than its own supposition, URS did not
identify an alternative source for OSHA to use as the basis for
estimates of ventilation capacity necessary to control silica
exposures.
    In response to these comments, and in order to determine whether
ACGIH recommendations had changed between the 24th edition (which OSHA
used to develop estimates in the PEA) and the more recent 28th edition,
OSHA checked its estimated volumes against those in the more recent
ACGIH Ventilation Manual (Chapter 13 in the 28th edition (Document ID
3883)). In the 24th edition of the Manual, ACGIH provided a single
recommendation for ventilation capacity rather than a range. In the
PEA, OSHA adopted this recommendation and did not choose a value from
within a range of values. The 28th edition of the Manual provides more
flexibility in system design and specification and incorporates a
recommended range. However, OSHA determined that the ventilation
capacity estimates did not change between the 24th edition of the
Manual and the 28th edition. In most cases, OSHA's estimated volumes
were identical to those recommended by ACGIH. The exceptions were
situations in which ACGIH provided no recommendation (in which case
OSHA relied on recommendations of industrial hygienists), and
situations in which the technological feasibility analysis recommended
additional volumes of LEV capacity above what employers were typically
using. In the latter situations, OSHA estimated that an additional 25
percent of the ACGIH specification would be necessary to adequately
control silica exposures (See Exhibit: Comparison of OSHA CFM Volumes
to ACGIH Values, available in Docket OSHA-2010-0034 at
www.regulations.gov).
    URS argued that silica was different from other substances LEV
might be applied to in ways that would call for higher volumes of
ventilation (Document ID 2308, Attachment 8, p. 14). However, in all
cases involving silica (such as shake-out stations), the ACGIH Manual
recommended the volumes used by OSHA and criticized by URS.
    OSHA's estimates of the ventilation capacity necessary to control
silica exposures relied on a detailed set of recommendations provided
by ACGIH while URS simply asserted that these values are ``most likely
undersized by a factor of 2 or more'' without providing additional
evidence to support this (Document ID 2308, Attachment 8, p. 12). Based
on these findings, OSHA has determined that the ACGIH recommendations
constitute the best available evidence and has maintained the estimates
of ventilation capacity from the PEA for the FEA.
Comments Providing Alternative Ventilation System Cost Estimates
    Other commenters provided much higher costs than OSHA's estimates
but without providing any background to allow OSHA to put those costs
in context. It is difficult for OSHA to evaluate a cost estimate
without information on the size of the facility, the estimated volume
of air, and the exposure levels before and after the LEV was installed.
    The Interlocking Concrete Pavement Institute (ICPI) commented that
OSHA underestimated compliance costs because ``[o]ne ICP manufacturer
reported that it could cost $150,000 to acquire and install highly
efficient vacuum and water dust-control systems'' and other
manufacturers reported similarly high costs (Document ID 2246, p. 11).
At the public hearings, OSHA sought clarification on the assumptions
underlying the ICPI cost estimate, and the ICPI representative stated
that $150,000 was a mid-range estimate. The representative also
confirmed that this was the cost of an entirely new system:

    MR. BLICKSILVER: [D]oes this actually represent the incremental
cost associated with complying with OSHA's proposed rule? . . . Or
is this an overall cost for dust control in these manufacturing
plants?
    MR. SMITH: The latter (Document ID 3589, Tr. 4407-4409).

    In a follow-up verbal exchange, OSHA requested that ICPI analyze
its survey data to produce median values for the range of cost
estimates and submit their analysis as a post-hearing comment (Document
ID 3589, Tr. 4409). However, no ICPI comments appeared in the record
following the Institute's testimony at the hearings.
    Similarly, OSHA asked Mr. Tom Slavin, testifying for AFS, for
additional information from AFS on the many cost estimates for
individual foundries that it had included in its comments:

    MR. BURT: You provide many examples of cost to specific
foundries of specific activities. I would like to suggest that those
can be most useful if we have data on the size of the firm in
question, the type of foundry if that's appropriate, and what they
were trying to accomplish with this effort.
    Were they at 400 and trying to get to 100, at 100 trying to get
lower? Something that puts it in context would again make these
many, many helpful quotes much more useful.
    Size is just critical, just because of the fact that when we
don't know whether we're talking about 20 or 200 people in a foundry
really affects what you want to do with those cost estimates. And
that one's relatively simple, size of firm, type of foundry if you
have it, what they were trying to do with that effort (Document ID
3584, Tr. 2773-2774).

    Later in the exchange, OSHA requested information on ``the
components of [AFS's estimated cost per cfm of additional ventilation]
that would be capital cost, installation cost, and then any other
operating costs you have'' (Document ID 3584, Tr. 2784). OSHA received
no response to this request.
    Unfortunately, it is almost impossible for OSHA to make use of
commenters' estimates of costs or volume of LEV systems without
information on the size of the facility and on what the resulting
system accomplished in terms of reducing exposure levels. OSHA
consistently requested this kind of

information, but did not receive it. As shown in the discussion of
alternative estimates of costs by small entity representatives during
the SBAR Panel (discussed below), even estimates that appear higher
than OSHA's average costs can be consistent with those costs when the
full context for the estimates is examined.
Comments and Responses on Unit Cost per CFM
    Many commenters thought that OSHA's unit costs for ventilation were
too low. With respect to the annualized value of the capital costs plus
operating and maintenance costs of $5.33 that OSHA used in the PEA, AFS
stated:

    The PEA uses an annual cost factor of $5.33 for ventilation,
including ducting and bag house operation [...] is far below foundry
experience. A group of foundry ventilation managers and ventilation
experts estimated the annual cost per CFM at $20 for exhaust alone
and another $6-10 for makeup air critical to achieving the lower
PEL. The cost to meet the new U.S. Environmental Protection Agency
(EPA) dust loading criteria increases the exhaust annual cost to $25
per CFM. Any new installation would be expected to design to the new
criteria even if not yet required to do so for that specific
jurisdiction (Document ID 2379, Appendix 3, p. 9).

    URS, commenting on behalf of ACC, estimated the annualized cost of
LEV to be $27 per cfm, and increased OSHA's original estimate of
capital costs from $12.83 to $22 per cfm for the purpose of URS's cost
estimate (Document ID 2308, Attachment 8, pp. 13-14).
    Many other commenters from industry suggested unit costs for
additional LEV. For example, AFS provided independent estimates of
annualized costs of $20 to $25 per cfm and URS estimated $22 to $27
capital costs per cfm (Document ID 2379, Appendix 1, p. 45; 2308,
Attachment 8, p. 14; 2379, Appendix 2, p. 13; 2503, p. 2; 2119,
Attachment 3, p. 4; 2248, p. 8; 3490, p. 3; 3584, Tr. 2779).
    OSHA agrees that there can be a wide range of both capital and
operating costs associated with LEV. Capital costs will vary according
to such factors as the exact nature of the ventilation (including the
design of the slot, hood, or bagging station), the volume of materials
to be handled by the ventilation, and the length of the ductwork
necessary. OSHA also would like to clarify that, as shown in OSHA's
spreadsheets (OSHA, 2016), where there are major structural changes
associated with a control, such as automation, a new bagging station,
or conveyor closure, these costs are estimated over and above the basic
capital costs of LEV. Annual operating costs vary according to climate,
hours of operation, and the extent to which air is recirculated. To
examine these possible costs, OSHA reviewed the thoroughly documented
LEV costs presented in its Final Economic Analysis for the Occupational
Exposure to Hexavalent Chromium Standard (Document ID 3641). In that
FEA, OSHA's estimates of the capital costs for LEV (updated to 2012
dollars) averaged more than $20 per cfm when major work station
changes, such as automated bag slitting stations, were included in the
cost of LEV. Ordinary additional LEV without major workstation changes
was estimated to have an average capital cost of $9 per cfm in 2012
dollars. Operating costs in that rulemaking were estimated to be
somewhat higher than estimated here, but combined annualized costs
(capital plus operating costs) were approximately the same (See
Exhibit: Analysis of LEV Costs from Hex Chrome, available in Docket
OSHA-2010-0034 at www.regulations.gov).
    OSHA agrees that the capital costs of some kinds of LEV that
involve significant workstation modifications or even automation can
exceed $20 per cfm, but finds an average of $13.34 (in 2012 dollars)
per cfm in capital costs to be reasonable given that some kinds of LEV
installation can cost as little as $3 to $5 per cfm. OSHA also finds
the operating cost estimates used in the FEA to be a reasonable average
across a very wide variety of circumstances.
Housekeeping and Dust Suppression Costs
PEA Costs
    For a number of occupations, the technological feasibility analysis
in the PEA indicated that improved housekeeping practices were needed
to reduce silica exposures. The degree of incremental housekeeping
depended upon how dusty the operations were and the appropriate
equipment for addressing the dust problem. The incremental costs for
most such occupations reflected labor associated with additional
housekeeping efforts. Because incremental housekeeping labor was
required on virtually every work shift by most of the affected
occupations, the costs of housekeeping in the PEA were significant. The
PEA also estimated that employers would need to purchase HEPA vacuums
and to incur the ongoing costs of HEPA vacuum filters. The time needed
for such housekeeping varied from five to twenty minutes per affected
worker per day. Appendix V-A in the PEA provided detailed
specifications on the application of housekeeping and other dust-
suppression controls in each occupational category and the sources of
OSHA's unit cost data for such controls.
    For some indoor dust suppression tasks, it was assumed that dust
suppression mixes--often sawdust-based with oil or other material that
adheres to dust and allows it to be swept up without becoming
airborne--were spread over the areas to be swept. For these products,
estimates were made of usage rates and the incremental times necessary
to employ them in housekeeping tasks.
    For outdoor dust suppression, the PEA determined that workers must
often spray water over storage piles and raw material receiving areas.
The methods by which water is provided for these tasks can vary widely,
from water trucks to available hoses. It was judged that most
facilities would make hoses available for spraying and that spraying
requires a materials-handling worker to devote part of the workday to
lightly spray the area for dust control.
    The PEA did not include any costs for thorough cleaning designed to
remove accumulated dust, either as a one-time cost or as an annual
cost.
Comments and Responses on Costs of Routine Housekeeping and Initial
Cleaning
    Commenters had a number of issues with respect to how OSHA treated
the costs of housekeeping, including the time and equipment needed for
vacuuming, the need for professional floor to ceiling cleaning, and the
costs of the ban on dry sweeping.
Comments and Responses on Costs of Routine Housekeeping
    With respect to the use of HEPA vacuums, AFS commented that due to
the volume of sand involved, foundries often use vacuum systems that
cost $45,000 instead of the $3,500 estimated by OSHA in the PEA
(Document ID 4229, Attachment 1, p. 23). Several commenters reported
that HEPA semi-mobile central vacuum systems cost more than $40,000 to
purchase and cost approximately $4,000 per year to maintain, and that
sweeping compound costs approximately $4,000 per year (Document ID
2384, p. 7; 2114, Attachment 1, p. 4). Several others noted that
acquiring HEPA vacuums and employee time for vacuuming would be
expensive (Document ID 2301, Attachment 1, p. 74; 3300, pp. 4-5; 2114,
Attachment 1, p. 4).
    OSHA's costs are for improved housekeeping, beyond the necessary
tasks related to dealing with the large volumes of sand used in
foundries. For this final rule, OSHA estimates the costs

of additional housekeeping as those necessary for overexposed workers
to spend 10 minutes vacuuming their immediate work areas with a 15-
gallon HEPA vacuum. It is possible that a large firm may find a dust
handling system or a semi-mobile central vacuum system less expensive
than having individual workers equipped with smaller capacity HEPA
vacuums spend additional time performing housekeeping on each shift.
    With respect to the shipbuilding sector, OSHA found that it had not
accounted for the costs of HEPA vacuums for abrasive blasting helpers.
OSHA has added costs for the vacuums, but not for the time spent
performing housekeeping as the vacuums replace dry sweeping.
    As to the possible costs of the ban on dry sweeping, OSHA has
modified this prohibition in ways that should avoid significant costs
in situations where dry sweeping is the only effective method of
housekeeping.
Comments and Responses on Costs of Initial Cleaning
    URS, testifying for ACC, questioned OSHA's omission of
``professional cleaning'' from its cost models for some industries,
noting that professional cleaning was identified in the PEA as
necessary for some industries to achieve the PEL (Document ID 2308,
Attachment 8, p. 12). URS also provided estimates of the cost of
professional cleaning:

    Based on communications with several industries, URS estimates
that a thorough annual professional cleaning will cost about $1.00
per square foot of the facility process operations area.
    . . . A professional cleaning can take several days to
accomplish [. . .] For square footage, URS assumed 20,000 square
feet for very small facilities, 50,000 square feet for small
facilities, and 200,000 square feet for large facilities (Document
ID 2308, Attachment 8, p. 24).

    Initial thorough facility cleaning and rigorous housekeeping are
supplemental controls and work practices addressed in the technological
feasibility analysis for the following application groups: Concrete
Products, Pottery, Structural Clay, Mineral Processing, Iron Foundries,
Nonferrous Sand Foundries, and Captive Foundries. OSHA failed to
include the costs of a thorough initial cleaning in the PEA, but has
developed estimates of these costs for the FEA in response to the URS
comment. The final standard sets the performance objective of achieving
the PEL using engineering controls, work practices, and where
necessary, respiratory protection, and, with respect to facility
cleaning and housekeeping, the rule does not mandate that firms hire
outside specialists. To estimate the final costs for initial thorough
facility cleaning, OSHA first developed an analysis of average
production floor space in square feet for two plant sizes based on data
on plant floor space and employment for individual facilities reported
in various NIOSH control technology and exposure assessment field
studies (OSHA examined Document ID 215; 216; 268; 1373; 1383; 3786;
3996; and 4114. The analysis is in Exhibit: Analysis of Plant Floor
Space, available in Docket OSHA-2010-0034 at www.regulations.gov).
    For the purpose of estimating cleaning costs, OSHA characterized
establishments with fewer than twenty employees as very small
establishments, and characterized establishments with twenty or more
employees as larger establishments.
    OSHA determined, based on a review of the data in the NIOSH field
studies, that production floor space averages 725 square feet per
employee (See Exhibit: Analysis of Plant Floor Space).
    For very small establishments with fewer than 20 employees, OSHA
used an average of 7 employees per establishment. For larger
establishments, OSHA used an average of 80 employees. (These estimates
of the number of employees are based on OSHA (2016), which shows that
the average number of employees for establishments with fewer than 20
employees is 7 employees and that the average number of employees for
establishments with more than 20 employees is 80 employees.) Based on
these parameters, OSHA's floor space model found that the typical floor
space for very small establishments is 5,075 square feet and for larger
establishments is 58,000 square feet.
    ERG spoke with a representative of an upper-Midwestern firm
specializing in the industrial cleaning of foundries and related
facilities (Document ID 3817, p. 2). According to that representative,
cleaning costs depend on numerous factors, such as the distance to the
facility that needs to be cleaned, the size and number of machines and
pieces of equipment present, the types of required cleaning activities,
and the presence of confined spaces. The representative described one
of his company's clients as a sand-casting foundry that produces 42,000
tons of gray and ductile iron castings per year in a 210,000 square
foot facility. According to the representative, a crew of two
technicians cleans the facility every 2 to 3 weeks at a cost of $2,200
to $3,500 per cleaning, which requires one day, or roughly $0.01 to
$0.02 per square foot in 2014 dollars.
    For the FEA, OSHA is estimating, based on data from the ERG field
interviews, that it will take 4 to 5 days to perform a one-time initial
cleaning (remove all visible silica dust) and that if the same facility
is cleaned every 2 to 3 weeks it will take 1 day to clean it. At a cost
of $0.02 per day per square foot, and using a cleaning duration of 5
days, OSHA calculated a cost of $0.15 per square foot in 2012 dollars
for an initial thorough cleaning. This value is derived from inflating
the 2003 estimate of $0.10 per square foot ($0.02 per day per square
foot over 5 days) to 2012 dollars, which raised the cost to $0.12 per
square foot. OSHA also allowed for an additional allotment of 25
percent of the estimated cost of $0.12 per square foot (in 2012
dollars) to ensure that the cleaning was sufficiently thorough to
achieve compliance, increasing the total from $0.12 to $0.15. OSHA
judges that this is a reasonable average for the range of facilities to
be covered, especially given that some annual cleaning is probably
already occurring at most facilities and therefore the full cost of
cleaning would not be attributable to this rule. The costs here are
applied to represent an incremental cleaning beyond that employed for
normal business purposes.
    As discussed earlier in this chapter, URS, an engineering
consultant to ACC, estimated that a thorough annual professional
cleaning will cost about $1.00 per square foot of a facility's process
operations area. URS provided no specific reference for that unit
estimate other than that it communicated with industry representatives
(Document ID 2308, Attachment 8, p. 24). The data OSHA used to develop
its cost estimates are based on interviews with a company that provides
housekeeping services rather than companies that may or may not have
purchased such services. OSHA's estimated costs for a thorough initial
cleaning are over five times the costs of a thorough cleaning where
there is just few weeks' worth of accumulated dust. Greater
accumulations during an initial cleaning do not mean that the initial
cleaning will cost 50 times the cost of a more basic/regular cleaning,
as much of the cost of the initial cleaning will be due to the time
spent going over the entire facility with the appropriate cleaning
devices--a cost that is fixed by area and not by accumulation. OSHA
therefore rejects the URS unit estimate of $1.00 per square foot as not
representative of a typical cost for initial thorough facility
cleaning, particularly for firms that choose to use in-house resources.
Nonetheless, OSHA

acknowledges that unique circumstances may create higher unit costs
than the value OSHA is using in the FEA. OSHA also acknowledges that
the cost of cleaning per square foot probably declines as facility size
increases (Document ID 4231, p. 4). The paucity of data on square
footage for the affected facilities, however, did not allow for further
modeling of cleaning costs.
    For this final analysis of costs for initial thorough facility
cleaning, OSHA estimated that an upfront, one-time, extensive servicing
(using vacuum and wash equipment) to rid the production area of
respirable crystalline silica during plant turnaround or other downtime
would cost $0.15 per square foot (including the additional allowance to
ensure a sufficiently thorough cleaning) or $0.02 when annualized at 3
percent for 10 years, and OSHA applied that unit cost along with the
average production floor space discussed above in OSHA's cost model
(725 square feet per employee) to derive final costs for facility
cleaning by application group. For the seven affected application
groups, OSHA estimates that annualized initial thorough facility
cleaning costs will range from just under $45,000 for Nonferrous Sand
Foundries to $488,000 for Concrete Products. Across all seven affected
application groups, OSHA estimates that annualized costs for initial
thorough facility cleaning will total $2.8 million.
Conveyor Covers
    The technological feasibility analysis in the PEA recommended
reducing silica exposures by enclosing process equipment, such as
conveyors, particularly where silica-containing materials were
transferred (and notable quantities of dust can become airborne), or
where dust is generated, such as in sawing or grinding operations. For
the PEA, OSHA estimated the capital costs of conveyor covers as $20.73
(updated to 21012 dollars) per linear foot, based on Landola (2003,
Document ID 0745) (as summarized in footnote a in Table V-3 of the
PEA). OSHA estimated that each work crew of four affected workers would
require 100 linear feet of conveyors. OSHA, based on ERG's estimates,
calculated maintenance costs as 10 percent of capital costs. Based on
the technological feasibility analysis, OSHA also included the cost of
LEV on the vents of the conveyors for the structural clay, foundry,
asphalt roofing, and mineral processing application groups, but not for
the glass and mineral wool application groups.
    URS commented that OSHA underestimated the length of conveyors by
using 100 linear feet in its estimate, and suggested that the estimate
of 200 feet that it used as the basis for its estimates was still an
underestimation for some foundries (Document ID 2307, Attachment 26,
Control Basis and Control Changes tabs). URS maintained OSHA's estimate
of $20.73 per linear foot in its own calculations. However, it appears
that URS did not understand that OSHA estimated 100 linear feet of
conveyors for every 4 workers, not 100 linear feet of conveyors for an
entire affected establishment. Further, the URS comment indicated that
100 linear feet was an underestimate for ``medium and large
foundries.'' But because OSHA's estimate of 100 linear feet is for
every four workers, OSHA actually estimated much longer conveyor
lengths for larger facilities with more workers. OSHA has determined
that its estimate of 100 linear feet for every four workers at a cost
of $20.73 per linear foot is a reasonable approach for estimating the
costs of conveyor covers.
Selected Control Options That Are Not Costed
    Consistent with ERG's cost model, in the PEA OSHA chose not to
estimate costs for some control options mentioned in the accompanying
technological feasibility analysis in Chapter IV of the PEA. In these
cases, OSHA judged that other control options for a specific at-risk
occupation were sufficient to meet the PEL. AFS identified several
control options for which OSHA did not estimate costs:

 Substitution of non-silica sand (V-A-51)
 Pneumatic sand handling systems (V-A-51)
 Didion drum to clean scrap for furnace operators (V-A-52)
 Non-silica cores and core coatings (V-A-52)
 Professional cleaning costs and associated downtime (V-A-52)
 Physical isolation of pouring areas (V-A-52)
 Modify ventilation system to reduce airflow from other areas
(V-A-52)
 Automation of a knockout process (V-A-53)
 Automated abrasive blast pre-cleaning of castings for
finishing operators (V-A-54)
 Wet methods (V-A-54)
 Low silica refractory (V-A-55) (Document ID 2379, p. 16)

    Just because a control is mentioned in the technological
feasibility analysis does not mean that OSHA has determined that its
use is required--only that it represents a technologically feasible
method for controlling exposures. The Agency developed cost estimates
based on the lowest cost combination of controls that allows employers
to move from an uncontrolled situation to meeting the new PEL. OSHA did
not include the costs for possible controls that were either more
expensive or were not necessary to achieve the PEL. OSHA (2016)
describes in detail which controls were considered necessary to achieve
the PEL. OSHA continues in the FEA to exclude costs for these kinds of
more expensive possible controls.
Railroads
    In its preliminary estimates, OSHA inadvertently applied the
preceding general industry PEL of 100 [mu]g/m\3\ in its analysis of the
railroad industry. Silica exposures among railroad employees, however,
result from ballast dumping, which is track work that is generally
subject to OSHA's construction standard and covered by the preceding
construction PEL of 250 [mu]g/m\3\ (see discussion of railroads in
Chapter III, Industry Profile). As a result, OSHA has changed its
conclusion that there would be no incremental costs for railroads to
meet the new PEL. OSHA has reassigned all costs previously assigned to
meeting the preceding PEL to being incremental costs of meeting the new
PEL. Although the railroad activities affected by the new silica rule
will typically constitute construction work, OSHA has categorized all
compliance costs for railroads with general industry costs under NAICS
482110 because the railroad industry is predominantly engaged in non-
construction work and its NAICS code is not typically classified as a
construction code.
Costs of Engineering Controls for Hydraulic Fracturing in the PEA
    Both in the PEA and in the FEA, OSHA presented the methods of
estimating the costs of controlling silica exposures during hydraulic
fracturing separately from the engineering control costs for all other
portions of general industry because there are some fundamental
differences in the methodology OSHA used, and thus in the comments OSHA
received on that methodology. In the PEA, OSHA began its analysis of
hydraulic fracturing in the standard way of examining the set of
engineering controls available to control employee exposures to silica.
Unlike the way OSHA handled the rest of general industry, however, for
hydraulic fracturing OSHA identified precisely which controls were
necessary to go from current levels of exposure to the preceding
general industry PEL of 100 [mu]g/m\3\ and then what further

controls would be necessary to go from the preceding general industry
PEL of 100 [mu]g/m\3\ to the new PEL of 50 [mu]g/m\3\. OSHA took a
different approach for this sector because the data available for this
industry, as a result of an extensive set of site visits, were adequate
to make this type of determination. OSHA determined that a combination
of wet methods, partial enclosure, and LEV controls would be sufficient
to meet a PEL of 100 [mu]g/m\3\ for hydraulic fracturing. OSHA then
determined that LEV controls at thief hatches and operator enclosures
would be sufficient to reduce exposures during hydraulic fracturing
from 100 [mu]g/m\3\ to 50 [mu]g/m\3\. The costs of these additional
engineering controls were shown in Tables A-14, A-15, and A-16 for
large, medium, and small fleets, respectively, in the PEA (the full
derivation of the results in these tables can be found in ERG, 2013,
Document ID 1712).
    As discussed in the Industry Profile section of the FEA (Chapter
III), the basic unit for analysis for this industry is the fleet rather
than the establishment. Rather than allocating costs according to the
proportion of workers above a given exposure level, as was done for the
rest of general industry, for hydraulic fracturing the controls applied
per fleet were judged to reduce the exposures of all workers associated
with the fleet.
Public Comments on OSHA's Preliminary Cost Estimates for Engineering
Controls in Hydraulic Fracturing
General Methodology
    Though there were extensive comments on OSHA's estimates of
engineering control costs for hydraulic fracturing, no commenter
objected to the differences in methodology compared to OSHA's treatment
of the other general industry sectors (as outlined above). Halliburton
Energy Services, Inc. commented that OSHA's analysis ``lacks data''
(Document ID 4211, p. 5). As discussed in Chapter IV Technological
Feasibility, OSHA agrees that there is limited experience with many
possible controls. For this reason, OSHA has allowed this industry an
extended compliance deadline of five years before they have to meet the
new PEL with engineering controls. However, OSHA does not agree that
this adds significant uncertainty to the costs analysis. The costs of
the controls OSHA has examined, and especially those needed to go from
the preceding general industry PEL to the new PEL can readily be
ascertained. It is possible that the cost of some controls that have
not yet been tested and that OSHA has not costed could be much lower
than the costs OSHA estimated in the PEA and in the FEA.
Compliance Rate
    In the joint comments submitted by the American Petroleum Institute
and the Independent Petroleum Association of America (API/IPAA or ``the
Associations''), the Associations disagreed with OSHA's estimated
current compliance rate for the use of engineering controls. In the
PEA, OSHA estimated a compliance rate of ten percent for engineering
controls in this industry. In their comments the Associations said that
``ERG assumed that 10% of all hydraulic fracturing firms already
utilize: (1) Baghouse controls; (2) caps on fill ports; (3) dust
curtains; (4) wetting methods; and (5) conveyor skirting systems''
(Document ID 2301, p. 40, fn. 148).
    While OSHA used a compliance rate of ten percent for all of these
controls, it is not meant to represent that all prescribed controls are
used in ten percent of firms. OSHA's compliance rates take into account
that some well sites, as documented in Chapter IV of the FEA, were
observed to be using a variety of controls that reduce dust levels, and
as a result, those firms will not need to implement as many additional
controls in order to achieve the new PEL. Further, as noted in Chapter
IV of the FEA, the industry is constantly installing additional
controls to reduce silica exposures. Thus the Agency sees no reason to
change its estimate of current compliance. In any case, removing the
assumption would make only a ten percent difference to the cost
estimates, which would not be a change of large enough magnitude to
threaten OSHA's conclusion that compliance with the final rule is
economically feasible for the hydraulic fracturing industry.
Maintenance Costs
    In the PEA, OSHA estimated that the life of most capital equipment
would be ten years, and that maintenance and operating costs would
range from ten to thirty percent of capital costs per year (ten percent
being most common).
    API/IPAA argued that the hostile, sandy environment of the well
site shortens the useful life of equipment and increases maintenance
costs. The Associations estimated that the useful life of equipment
ranges from 5 years to 7.5 years and that annual operating and
maintenance costs range from 10 percent to 25 percent of capital costs.
While OSHA agrees that the oilfield environment is challenging and
dusty, there is no evidence in the record that these environments are
more challenging than other industrial settings where equipment lives