operations'' in the proposed rule has been broken out into two groups:
(1) Heavy equipment operators and ground crew laborers used for
activities such as grading and excavating that will not involve
demolition or other uses that will abrade or fracture silica-containing
materials; and (2) heavy equipment operators and ground crew laborers
involved in demolition or the abrading or fracturing of silica-
containing materials. These two categories are now estimated to have
productivity impacts of two and three percent, respectively.

[GRAPHIC] [TIFF OMITTED] TR25MR16.052

Productivity Impact Estimates, by Equipment Category
Rock and Concrete Drilling
    This equipment category includes the following Table 1 tasks:
     Dowel drilling rigs for concrete; and
     Vehicle-mounted drilling rigs for rock and concrete
    This equipment category covers a range of drilling activities using
truck-mounted and similar drilling equipment, such as quarry drills and
crawler-type drills. Dust control requires the use of either a dust
collection system or wet drilling methods. Studies of the effectiveness
of available dust collection systems have not addressed performance
issues, but ERG judged that their use does not affect drilling
productivity. While workers must service the dust control equipment
during the workday, this activity generally does not affect the rate of
drilling, except perhaps for short-duration jobs. The wet drilling
methods are integrated into drilling equipment and also should not
adversely affect the drilling rate. Thus, OSHA estimates that there
will be no lost production time for these tasks.
Tuckpointers and Grinders
    This equipment category includes the following Table 1 tasks:
     Handheld grinders for mortar removal (i.e., tuckpointing);
and
     Handheld grinders for uses other than mortar removal
    According to ERG's search of the literature, grinding tools can be
retrofitted with dust control shrouds that connect to a vacuum system
(Buser, 2001 & 2002, Document ID 0577). Studies on the use of these
controls indicate that extra time is required to install the shroud and
periodically

clean, empty, or replace the vacuum drums, filters, or bags. The
estimated time to install the shroud may be as short as five minutes,
although some types of shrouds take longer to install. Once installed,
however, the shroud can be left in place for the work at that location,
so this activity need not take place at the initiation of each grinding
job.
    For interior jobs and for exterior work that requires site cleanup
of grinding debris, the additional work time required to use a vacuum
system might be partially offset by savings in the time required to
seal work areas (to prevent dust migration) and to clean the work area
after task completion. Overall, clean-up times will vary depending on
the size of the job site, the quantity of grinding debris, and the
strength and capacity of the vacuum.
    Grinding without a dust-control shroud can generate clouds of dust
that might impair a worker's views of the grinding area. Whereas metal
shrouds also block the view of the grinding area, plastic shrouds allow
workers a view of the work area. Some contractors have noted, however,
that use of shrouds does not allow for the precision required for
certain tasks, such as grinding an inside corner (Lattery, 2001,
Document ID 0777).
    For exterior jobs where cleanup is not required and where the work
area is not sealed, the use of vacuum equipment is likely to decrease
productivity for the amount of time required for servicing the vacuum
collectors. If, for example, five minutes were required to empty the
vacuums every two hours, production time would decline about 4 percent,
due simply to dumping the accumulated dust.
    At some construction sites, vacuums have been used during the
grinding process, but without shrouds. In these cases, one worker
typically holds the vacuum nozzle near the grinding tool, which another
worker operates. Switching to shrouds with a direct vacuum attachment
would eliminate the need for this assistant and is a more productive
operation.
    Manufacturers and vendors cited other benefits from using the
shroud-vacuum systems. Because dust does not build up on and clog the
surface of the grinding wheel, the wheels last longer, resulting in an
approximate 40 percent savings on the grinding discs (Eurovac, 2001,
Document ID 0688). Another source contacted by ERG estimated that
shrouds can increase the abrasive life of a grinding wheel by more than
500 percent (Buser, 2001 & 2002, Document ID 0577). In this regard,
workers would spend slightly less time replacing wheels over the life
of the equipment.
    OSHA concluded that while the productivity impacts of vacuum
systems can sometimes be partly offset by other factors, net
productivity impacts are likely to remain negative. For exterior work,
productivity is clearly lower when workers use a vacuum system.
Overall, based on ERG's research, OSHA's final cost estimates include a
5 percent impact for lost production time associated with grinding
operations in construction. This productivity impact is identical to
the impact estimated for this activity in the PEA.
    For a tuckpointing project, NIOSH researchers examined the use of
vacuum system controls at a large college building complex (Gressel et
al., 1999, Document ID 0718). Workers used a shroud-vacuum system with
an integral impeller and a fabric dust collection bag. This system
required emptying the collection bags about once an hour. The authors
reported some problems caused by blocking and kinking of the hose and
occasional separations of the hose from the tool. Some of these
problems can be attributed to the design of the dust control system and
might be rectified by future design innovations. Overall, the vacuum
control systems appeared to reduce worker output.
    Manufacturers and vendors contacted by ERG estimated that
polyurethane shroud-vacuum systems with tuckpointing equipment, similar
to those used with hand-held grinders, actually enhance productivity.
Among the reasons provided for productivity improvements were: (1)
Fewer workers were required; (2) cleanup times were reduced; (3)
workers had improved visibility of the work surface; and (4) blades
last longer (Buser, 2001 & 2002, Document ID 0577; Caperton, 2002,
Document ID 0580; Eurovac, 2001, Document ID 0688; Nash and Williams,
2000, Document ID 0829). These observations on productivity applied to
tuckpointers with 2- to 8-inch diameter wheels. In addition, positive
effects on worker productivity have also been reported for shrouds that
fit on 5-inch and 7- to 8-inch (18-lb) tuckpointers with integrated
dust-collection systems since equipment without integrated dust-
collection systems require that an additional worker be present to
continually vacuum dust away from the work area (Document ID 0577). On
the equipment that can be used with the tuckpointers with 5- to 8-inch
wheels, an impeller inside the tool housing pushes dust down a hose
into a reusable dust-collection bag (Document ID 0577). One vendor
estimated that the operational productivity of these tools is no
different from that of the same tool without dust control capability.
Workers would still be required to periodically empty dust bags,
although other clean-up time might be somewhat reduced (Document ID
0580). Because tuckpointing work is almost exclusively exterior work,
however, clean-up is often not required.
    Based on the considerations for hand-held grinding tools discussed
above and the findings from the NIOSH tuckpointing study, OSHA judged
in the PEA that use of a vacuum system during tuckpointing operations
would impose, on average, a 5 percent negative productivity impact.
Based on these findings and because manufacturer optimism about any
positive productivity impacts has not been documented in controlled
studies, OSHA included the same 5 percent negative productivity impact
for tuckpointing tasks in the FEA.
Heavy Equipment Operators and Ground Crew Laborers
    This activity includes the following Table 1 tasks:
     Heavy equipment and utility vehicles used to abrade or
fracture silica-containing materials (e.g., hoe-ramming, rock ripping)
or used during demolition; and
     Heavy equipment and utility vehicles for tasks such as
grading and excavating but not including: Demolishing or abrading or
fracturing silica-containing materials \41\
---------------------------------------------------------------------------

    \41\ Heavy equipment operations (grading and excavating) was
referred to as earth moving in the PEA and in comments. The term has
been updated for this analysis and used throughout for the sake of
consistency and to avoid confusion.
---------------------------------------------------------------------------

    The control method proscribed in the proposed silica standard was
to enclose and ventilate the operator's cab. The requirement for an
enclosed cab is only retained in the final standard with respect to the
use of heavy equipment used to abrade or fracture silica-containing
materials or used during demolition. Final Table 1 allows employers to
control dust from heavy equipment used for other purposes (e.g.,
grading or excavating) by using wet methods.
    Using an enclosed cab on heavy construction equipment will not
require maintenance beyond the general maintenance necessary to
maintain the integrity of the cab enclosure. Therefore, OSHA estimated
in the PEA that no productivity loss will be incurred for this control.
    In the case of heavy equipment operations, CISC/Environomics
estimated that there would be a one percent productivity penalty for

enclosed cabs, due to communication issues and the need to unclog HEPA
filters (Document ID 4217, p. 93). For several reasons OSHA is not
persuaded that the factors CISC cites would result in a net
productivity loss for enclosed cabs on heavy equipment.
    First, it is not clear that communication issues are being created
by setting some minimal standards for enclosed cabs. Information
supplied in the record indicates that there are alternate means of
communication beyond shouting from the cab to the front-line workers
outside the cab, including hand signals (Document ID 3583, Tr. 2441)
and existing wireless communication systems (Document ID 0805, p. 4;
2262, p. 28). Many of these work environments are noisy, which seems to
make alternate means of communication desirable, if not required.
    Second, it appears that it may be more economical and desirable for
workers to operate in a climate-controlled cab and that equipment with
enclosed cabs has become standard in the construction industry. In
fact, OSHA has determined that relevant heavy equipment currently comes
with an enclosed cab as standard equipment (Document ID 3813, 3814,
3815, 3816), and in pricing construction jobs, RS Means included a cab
as a standard equipment (meaning that it was already included in the
equipment cost, not an added engineering control). In any case, the
fact that cabs are standard suggests that potential buyers do not view
the presence of a cab to be undesirable. While Environomics
acknowledged this possibility at the hearings, their judgment remained
that there would be a net productivity loss (without providing
information on how these offsetting considerations were being
incorporated) (Document ID 3580, Tr. 1434-1435). While OSHA is not
persuaded that the evidence in the record supports Environomics
conclusions, their argument is largely moot. Any productivity impact
would result only from the addition of new controls, but enclosed cabs
appear to have become standard on the relevant equipment, meaning that
in most cases employers would not have the option of using open cabs
even if OSHA's new rule was not in effect. Thus, there can be no
productivity impact attributed to the requirement for a cab.
    Although OSHA is not including any productivity impact to account
for enclosed cabs, final Table 1 requires water, or other dust
suppressants, during specified heavy equipment operations in order to
protect workers outside the cab and as an alternative method of
protecting operators for activities that do not involve silica abrading
or fracturing. OSHA has therefore, as indicated in Table VII-12, added
a 2 percent productivity impact for heavy equipment tasks involving
grading and excavating, and 3 percent during demolishing, abrading or
fracturing silica-containing materials. OSHA judged that the abrading,
fracturing, and demolition-related tasks tend to be relatively dustier,
and would therefore require relatively more labor to administer.
Hole Drilling Using Handheld or Stand-mounted Drills
    This equipment category includes the Table 1 task ``handheld and
stand-mounted drills (including impact and rotary hammer drills).''
    This category includes workers in the construction industry who use
handheld drills to create clearly defined holes for attachments (e.g.,
anchors, bolts, hangers) or for small openings for utility pass-
throughs in concrete and other silica-containing construction
materials. Workers use common electric drills, pneumatic drills,
handheld core drills, stand-mounted drills, rotary drills, rotary
hammers, percussion hammer drills, or other impact drills to drill
holes. With regard to core drills, only small, handheld core drills
with bits up to a few inches in diameter are included in this category.
This discussion does not address the use of portable and mobile hole
saws used to produce large holes or openings. That equipment is covered
in the discussion of Masonry and Concrete Cutters Using Portable Saws.
    Handheld and rig-mounted drills can be equipped with local exhaust
ventilation to effectively capture dust generated when drilling small
diameter holes. Larger core drills, also referred to as core saws, are
more frequently used with water as a coolant to extend the service life
of the drill bit, as well to suppress dust.
    One rock-drill manufacturer asserts that use of vacuum systems
speeds drilling by continuously removing the drill cuttings from the
hole, making it unnecessary for workers to periodically stop drilling
to accomplish this task (Atlas-Copco, 2001, Document ID 0542). On the
other hand, the connection and servicing of the vacuum equipment
requires incremental work that could reduce productivity. If the
construction project at hand involves interior work, this impact might
be offset by reductions in the time necessary for cleanup (i.e.,
interior work would require cleanup, while exterior drilling probably
would not). In the PEA, OSHA applied a 2 percent productivity impact
where this task is performed and did not receive comment suggesting
that this estimate was too low, so OSHA retains the same 2%
productivity impact in estimating compliance costs in the FEA.
Jackhammers and Other Powered Handheld Chipping Tools
    This equipment category includes the Table 1 task ``Jackhammers and
handheld powered chipping tools.''
    Silica exposures generated during pavement breaking, concrete
demolition, and other concrete work using jack hammers and other
handheld powered chipping tools (including pavement breakers and other
similar tools) are controlled through the use of wet or dry methods.
    Regarding wet methods, because the work area generally cannot be
presoaked effectively (i.e., dust is generated once impact drillers
break through the surface), OSHA judged that adequate dust control
requires a constant spray of water to the work area. Thus, dust control
requires that a water sprayer be mounted onto the jackhammer (or that a
mobile sprayer be set up that can move along with the work).
Alternatively, a crew member can use a water hose to spray and wet the
concrete and asphalt surfaces being broken, although the associated
productivity loss could be substantial, and, for that reason, OSHA
believes that construction firms would likely try to avoid that
approach.
    However, OSHA judged that the incremental productivity impact from
the spraying activity is modest because various crew members could
occasionally be enlisted to keep the water spray directed in the
correct location. Further, because of the interactive nature of the
various crew member activities, the time to move the water sprayer is
unlikely to affect the overall crew output. In addition, incremental
cleanup costs generally would not be significant since most drilling
projects are performed outside. Nevertheless, to allow for some
incremental work related to supplying water and positioning the spray
when wet methods are used, as was the case in the PEA, for the FEA OSHA
estimated a 3 percent productivity impact for this equipment category
when wet methods are used.
    A separate, higher, productivity impact was defined for use of dry
methods for activities where jackhammers and other handheld powered
chipping tools are used. Dry methods are somewhat less flexible and
require a shroud for the close capture of dust as it is generated
during operations. Workers also periodically have to empty

the vacuum bags in which the dust accumulates. Thus, as discussed above
with respect to the use of a shroud for grinding and tuckpointing,
these controls are judged to generally have a greater productivity
impact during operations and, consistent with the PEA, OSHA assigned a
5 percent productivity impact to use of this control method for this
equipment category.
Masonry and Concrete Cutters Using Portable Saws
    This equipment category includes the following Table 1 tasks:
     Handheld power saws (any blade diameter);
     Handheld power saws for cutting fiber-cement board (with
blade diameter of 8 inches or less);
     Rig-mounted core saws or drills;
     Walk-behind saws; and
     Drivable saws
    Drivable saws and walk-behind saws have an integrated water tank,
and the sawing is almost always done wet (see FEA Chapter IV,
Technological Feasibility). Wet sawing keeps the blade from
overheating, with the water acting as coolant. Rig-mounted core saws
used to drill larger diameter holes in concrete are typically used with
water as a coolant to extend the service life of the bit, as well as to
suppress dust.
    As has been noted, most portable hand-held concrete saws are
designed with wet-sawing capability (see Chapter IV, Technological
Feasibility of the FEA). These saws have a water hookup for a hose
attachment, but might also be used for dry cutting. (Dry-cut diamond
blades for dry cutting are available; these are made especially so that
the tips do not separate during dry cutting.)
    A construction equipment distributor judged that there are no
operational productivity advantages for dry cutting, as opposed to wet
cutting (Healy, 2002, Document ID 0726). Wet cutting, however, requires
access to water (water line or pressurized tank), and some time is
needed to connect the equipment (although OSHA received a number of
comments saying that this hook up is very simple and not time
consuming--see ``Public comments suggesting that OSHA underestimated
the productivity impacts associated with engineering controls'' earlier
in this section for more detail). In addition, the water hose hookup
may be cumbersome and interfere with the work (Healy, 2002, Document ID
0726). For these reasons, as was estimated in the PEA, for the FEA,
OSHA assigned a cost of 2 percent in lost production time for equipment
in this category.
    For the final rule, the Agency has clarified in Table 1 that hand-
held circular saws with a blade diameter of eight inches or less
specially designed for cutting fiber cement board can be used outdoors
without respiratory protection, when equipped with a local exhaust
ventilation. The productivity impact for this group is also estimated
at 2 percent because, although it does not have an impact on job
performance, it involves some set-up time and incremental maintenance.
Masonry Cutters Using Stationary Saws
    This equipment category includes the Table 1 task ``Stationary
masonry saws.'' Stationary saws for masonry, brick, and tile cutting
come equipped with water systems for wet cutting, which is the
conventional, baseline control method for this type of work. Some
modest incremental time is needed to provide for and connect the water
supply and to maintain the water nozzles and spray system. This
incremental time was the basis for OSHA to estimate a 2 percent cost in
lost production, both in the PEA and in the FEA.
Millers Using Portable or Mobile Machines
    This equipment category includes the following Table 1 tasks:
     Walk-behind milling machines and floor grinders;
     Small drivable milling machine (less than half-lane);
     Large drivable milling machines (half-lane and larger with
cuts of any depth on asphalt only and for cuts of four inches in depth
or less on any other substrate)
    The activities performed using equipment in this category range
from cold planing and cleaning of asphalt to surface planing or
grinding of concrete. In large-scale projects, such as street
resurfacing, baseline practices are judged to control silica dust
exposures. No additional controls would be needed, and therefore no
negative productivity impacts are expected.
    While some grinding machines designed for milling concrete surfaces
have built-in dust collection or wet-method systems, others must be
attached to external vacuum equipment. ERG reviewed the available
literature and found no evidence that the grinding operation is slowed
when such vacuum equipment is attached. Nevertheless, workers must
devote some time to setting up equipment, changing vacuum bags or
barrels, and cleaning filters. On the other hand, using an LEV system
to capture dust as it is generated reduces the time required for
cleaning up the settled dust from the surfaces following completion of
the grinding task. OSHA estimated in the PEA that there would be a 2
percent productivity impact for milling using wet methods and a 5
percent productivity impact when using LEV systems.\42\ These estimates
have been retained for the FEA.
---------------------------------------------------------------------------

    \42\ For the FEA, milling operations using LEV are accounted for
under grinding operations, as indicated in Table V-24.
---------------------------------------------------------------------------

Mobile Crushing Machine Operators and Tenders
    This equipment category comprises the Table 1 task ``Crushing
machines.''
    OSHA projected in the PEA that there would be no productivity
impact for this equipment category. The Table 1 requirements for this
machinery have changed in the final rule, but OSHA's conclusion that
there will be no productivity impact remains the same. Final Table 1
requires employers to protect employees through a combination of
sprayers and requiring the operator to operate the machinery from
within a ventilated booth or at a remote control station. Once
installed, the sprayer systems will be part of the crushing machine
operation and will not impact production rates. For the purpose of the
economic analysis of this rule, OSHA has accounted for additional costs
for use of the ventilated booth. Because the booth can be located close
to the machinery, there would not be productivity loss from the
operator having to travel to a different location for operation. In
most cases the booth can be set up quickly once at each location, so in
most cases there will not be any significant productivity loss
associated with the use of the booth.
Baseline and Incremental Unit Control Costs
    Table V-34 in the FEA, and presented as Table VII-13 in this
section, summarizes the control method and costs per day for each
representative construction job. These costs include incremental
equipment costs and indirect labor costs due to productivity impacts
(decreases in productivity associated with the use of the control
equipment).
    Note that the only silica tasks in Table V-34 of the FEA considered
to have short-term infrequent work where the employee would own the
equipment are Task 11: Hole drilling using hand-held or stand-mounted
drills and Task 18: Masonry cutting using portable saws--II. Note also
that all the indoor tasks in Table V-34 of the FEA have an additional
daily control equipment cost of $1.67 for a fan.

    Table V-35 of the FEA summarizes the baseline costs and incremental
control costs from Tables V-30 and V-34, of the FEA, respectively, for
each representative silica-related job in OSHA's silica construction
cost analysis. The control cost (defined as incremental control costs
per day) are shown in Table V-35 of the FEA as a percentage of the
baseline daily job costs. As the incremental control costs were
obtained from Table V-34, they are just the sum of additional labor and
equipment costs associated with the use of silica controls, including
the labor and equipment productivity impacts of the use of the silica
controls.
    As is evident from Table V-35 of the FEA, these incremental control
costs can range from 0.3 percent to 7.8 percent of the baseline job
cost. The magnitude of the productivity impacts can substantially
change the estimate of the overall cost increase associated with the
silica dust controls.
    Table V-36a of the FEA presents the weighted average of control
costs by task category for outdoor tasks. OSHA defined ``weights'' for
each job category (column ``Relative Frequency Within Categories'')
based on the projected relative applicability of the controls and/or
tasks within each category (as determined in the technological
feasibility analysis in Chapter IV of the FEA). These percentages did
not change from the PEA except for the two tasks that have each been
further partitioned into multiple tasks in the final rule: Heavy
construction operators and masonry cutters using portable saws. Heavy
equipment operators are subdivided into tasks that involve fracturing,
abrading, or demolishing silica-containing materials such as masonry or
concrete, that require use of wet methods whenever workers other than
the equipment operator are present, and tasks that involve use of heavy
equipment for earthmoving and excavation of soil, that require wet
methods only as necessary to minimize fugitive dust. Masonry cutters
using portable saws are subdivided into five categories: (1) Handheld
power saws such as cutoff saws; (2) handheld power saws for cutting
fiber-cement board with blade diameters of less than eight inches; (3)
walk-behind saws; (4) drivable saws; and (5) rig-mounted core saws. Wet
methods are specified as a control method for all use of portable saws
except for handheld power saws for cutting fiber-cement board, for
which LEV rather than use of water to suppress dust is required. The
labor cost as a percentage of project costs--which, as subsequently
shown, is a critical factor in calculating the total value of all
silica-generating construction activities--is derived from Table V-30
of the FEA.
    Table V-36b of the FEA presents the weighted average of control
costs by task category for tasks indoors or in enclosed areas (``indoor
tasks''). The procedures are identical to those used in Table V-36a of
the FEA, and the only difference is that the total incremental costs as
a percentage of baseline costs are higher due to the addition of the
cost of a fan for indoor tasks.
    Once the total value of all silica-generating construction activity
is calculated for each task, as shown in Table V-44 of the FEA, the
incremental costs associated with each task category as a percentage of
baseline costs (from Tables V-36a and V-36b of the FEA) will determine
the costs that the engineering control requirements in the final
construction standard add to the costs of construction activity--that
is, the incremental costs of the resulting reduction in silica
exposure.
Aggregate ``Key'' and ``Secondary'' Labor Costs for Representative
Projects
    To estimate aggregate labor costs or value for each equipment
category, OSHA first matched OES occupational classifications with the
labor requirements for each equipment category (e.g., hole drillers
using hand-held or stand-mounted drills). These matching occupations
are shown in Table V-37 of the FEA. In order to estimate the percentage
of time during each work day that workers spend on activities using
equipment in the relevant categories, OSHA designated some occupations
as ``key'' and others as ``secondary.'' The key field in Table V-37 is
set to ``1'', if a key occupation and to ``0'' if a secondary one. Even
those employees who are engaged in tasks on Table 1 typically spend
only a portion of their workdays engaged in silica-generating tasks, so
the distinction between ``key'' and ``secondary'' is needed in order to
estimate the amount of time workers participate in silica-generating
tasks. In the preliminary and final cost analyses, OSHA applied ERG's
occupation designation, as explained in greater detail below. OSHA
requested comment on the designations of ``key'' and ``secondary''
designations in the PEA, but did not receive any comments challenging
those designations.
    ``Key'' occupations refer to the worker or workers on each crew who
perform the principal silica-generating activity using the equipment in
each equipment category. For each equipment category, ERG estimated the
overall percentage of time that workers in key occupations devote to
the activity.
    Other ``secondary'' crew members (e.g., first-line supervisors/
managers and construction laborers) were estimated in terms of their
ratio to the number of key workers required for given task areas. The
secondary crew ratios range from 0 percent (no one in a secondary
occupation engaged in silica-generating tasks) to 300 percent (three
times the number of secondary occupation workers, in relation to the
number of key workers, exposed to silica-generating tasks). As noted
above, OSHA used these percentages and ratios to estimate (on an annual
basis) the amount of time these employees are using relevant equipment
to engage in work that causes silica exposures. The estimate of the
percentage of time performing the silica-generating activity can be
viewed in terms of the full-time-equivalent (FTE) employees engaged in
work that utilizes equipment in each equipment category. These
estimates and the corresponding ratios for secondary workers are shown
in Table V-37 of the FEA.
    For the key occupations, OSHA was able to obtain some data with
which to estimate the proportion of time workers perform activities
using silica-generating equipment. For the secondary occupations, such
estimates were generally not possible. Thus, the participation of
secondary occupations in silica-generating activities was defined based
on their relationship to the key occupations. This participation is
defined by their presence in the job crews, as shown in Table V-30 of
the FEA. To illustrate the need for this approach, consider the
difficulty in predicting how often construction foremen of all types
are present during activities where silica-generating equipment is
used. BLS data, for example, provide only a total number of foremen,
but no information about how they might spend their time. It is
reasonable to forecast, however, using the job-crew definitions, that
foremen will be present in some proportion to the number of workers in
key occupations using jackhammers and other powered handheld chipping
tools, rock and concrete drillers, and other silica-generating
equipment. OSHA presented these data in the PEA and requested comments,
but did not receive any on this aspect of the analysis. Therefore, OSHA
is retaining its estimates from the PEA, except as noted.
    For some activities, the crew size and composition vary among the
jobs defined in the equipment category. In those cases, OSHA used ERG
determinations as to the most representative crew composition and used
that crew model to define the ratio

of secondary to key occupations (ERG, 2007a, Document ID 1709).
    The estimates of the number of FTE employees engaged in activities
using silica-generating equipment are one of many factors that
influence the final cost estimates. There are few data, however, on the
breakdown of time spent by construction workers in various activities.
The following discussion presents the basis for the time-on-task
estimates for the key occupations as included in the PEA and the FEA
(except where noted). OSHA presented most of these estimates for public
comment in the PEA but did not receive any comments challenging them.
Rock and Concrete Drillers
    A review of NIOSH reports covering rock and concrete drillers
showed that over 75 percent of driller time was spent on actual
drilling (NIOSH 1992a, Document ID 0911, NIOSH 1992b, Document ID 0910,
NIOSH 1995, Document ID 0907) and is supported by updated data in
NIOSH, 1999b (Document ID 0220). Therefore, for the PEA and FEA, OSHA
used 75 percent as the best indication of the time spent using dust-
generating equipment for workers in this category.
Tuckpointers and Grinders
    Grinding and tuckpointing are only two of the numerous jobs
performed by brickmasons, cement masons, and their helpers. Workers in
those trades are much more frequently performing bricklaying, cement
work, and masonry construction. Where tuckpointers and grinders are
being used, a review of the OSHA Special Emphasis Program reports
revealed that the time spent using tuckpointers and grinders varied
widely (see the technological feasibility analysis for this activity in
Chapter IV of the FEA). In both the PEA and in the FEA, OSHA used ERG's
estimate that 2.5 percent of the time for workers in each of the
applicable occupations would be spent on using this equipment.
Heavy Equipment Operators and Ground Crew Laborers
    For the final rule, heavy equipment operators and ground crew
laborers were split into two categories in Table 1 based on how the
heavy equipment and utility vehicles are being used, which reflects
distinctions added in the final rule. This equipment is considered to
either be used a) to abrade or fracture silica-containing materials
(e.g., hoe-ramming, rock ripping) or used during the demolition of
concrete or masonry structures; or b) for tasks such as grading and
excavating but not including: demolition of concrete or masonry
structures or abrading or fracturing silica-containing materials.
    ERG estimated that workers using heavy equipment to abrade or
fracture silica-containing materials or for demolition devoted only 2.5
percent of their time, on an FTE-equivalent basis, to doing this work.
    Key workers in the companion group using heavy equipment for
grading and excavating often spend the bulk of their work shift on the
equipment itself, engaged in construction work. OSHA Inspection Reports
and other documentation consistently show that heavy equipment
operators perform their tasks for more than 7 hours per shift (OSHA SEP
Inspection Reports 122212079, 116179359; Greenspan, et al., 1995; NIOSH
HETA 93-0696-2395, 1999; NIOSH, 1999b; NIOSH ECTB 233-120, 1999c.).\43\
Nevertheless, the heavy equipment operator occupational category also
includes operators of such equipment as pile drivers, cranes, and air
compressors that are not generally associated with silica dust
generation. For the PEA, OSHA used ERG's estimate of 75 percent for
operating engineers and 50 percent for excavating and loading machine
and dragline operators in this category to estimate the number of heavy
equipment operators performing silica-generating activities. OSHA did
not receive any comment on these estimates and therefore has retained
their substance for the FEA.
---------------------------------------------------------------------------

    \43\ Document ID 0133, 0192, 0716, 0220, and 0266, respectively.
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Hole Drilling Using Handheld or Stand-Mounted Drills
    While many workers might occasionally be assigned to drill holes in
concrete, this equipment category represents a very small part of the
activities of the occupational groups performing this work. ERG judged
that carpenters, electricians, plumbers, sheet metal workers, and
helpers (construction laborers) spend one percent of their time
drilling holes in silica-containing materials in the affected
industries. OSHA presented this estimate in the PEA and did not receive
comment or alternate estimates and has therefore retained the estimate
for the FEA.
Jackhammers and Other Powered Handheld Chipping Tools
    OSHA estimated in the PEA that in the key occupation of
construction laborers, relatively few use equipment in this category.
In developing the estimate of time spent using equipment in this
category for the PEA, ERG examined a snapshot of construction
activities from the BLS publication, Injuries to Construction Laborers
(BLS, 1986, Document ID 0559). That source presents a survey of injured
construction workers and includes questions about their activities at
the time they were injured. The survey indicated that 3 percent of
construction workers were using jackhammers at the time they were
injured. ERG judged that, while the survey was not intended to
characterize typical construction activities, and a survey of injured
workers introduces considerable potential bias into the observations,
this estimate was useful as an observation of representative
construction activities. ERG also judged that, because jackhammers are
heavier, more cumbersome, and more powerful than much construction
equipment, workers are probably injured more frequently while using
jackhammers, on average, than when using all other construction
equipment. Thus, the 3 percent figure is likely to be an upper bound of
the amount of time spent using jackhammers and other powered handheld
chipping tools. In the absence of other data, OSHA used ERG's estimate
that 3 percent of laborers are using this equipment for the PEA. The
Agency received no additional data or comment on this estimate and has
therefore retained this estimate for the FEA.
Masonry and Concrete Cutters Using Portable Saws--I
    The key occupations using portable saws to cut masonry and
concrete, namely brickmasons, blockmasons, stonemasons, and their
helpers, spend, on average, a small share of their time cutting these
materials with portable saws. In Table 1, OSHA notes three types of
portable saws: (1) Hand-held saws, (2) walk-behind saws, and (3)
drivable saws. Each of those is encompassed in this analysis, although
small-diameter handheld saws are addressed separately. According to
OSHA and NIOSH reports, the workers in these occupations perform
multiple masonry activities and might engage in cutting for only a
small portion of their shift (OSHA SEP Inspection Report 300646510;
NIOSH, 1999a) (Document ID 0084). Another glimpse of this activity can
be gleaned from the BLS injury report for construction laborers, where
3 percent of workers were injured while breaking up or cutting
concrete, asphalt, brick, rocks, etc. For each of the applicable
occupations, OSHA estimated in the PEA that 10 percent of the workers'
time would be spent using

the equipment in this category. The Agency received no comment on this
estimate and has therefore retained this estimate for the FEA.
Masonry and Concrete Cutters Using Portable Saws--II--Small Diameter
Saws for Cutting Fiber-Cement Board
    The task of using handheld power saws for cutting fiber-cement
board (with blade diameter of 8 inches or less) was separated out in
Table 1 in the final rule to recognize portable saws used for cutting
cement fiberboard or cement fibersiding as a potential source of
silica-containing dust. OSHA judged that portable saws would be used by
carpenters or their helpers to cut fiber-cement board and that, on
average, they would spend 2.5 percent of their time using equipment in
this category to cut the referenced materials.
Masonry Cutters Using Stationary Saws
    As noted earlier, OSHA and NIOSH surveillance publications report
that saw operators perform multiple masonry cutting activities and
might engage in cutting silica-containing materials for only a small
portion of their shift (OSHA SEP Inspection Report 300646510; NIOSH,
1999a). For the PEA, OSHA used ERG's estimate that workers in mason
occupations spend 10 percent of their time cutting silica-containing
materials with stationary saws. The Agency received no comment on this
estimate and has therefore retained this estimate for the FEA.
Millers Using Portable or Mobile Machines
    In the PEA, ERG identified two key occupation groups where millers
are using portable or mobile machines: (1) Cement masons and (2)
paving, surfacing, and tamping equipment operators. In response to
comments (see Document ID 3585, Tr. 3036; 4220, p. 9; 3756, Attachment
1), for the FEA, OSHA added a third key occupation group: Terrazzo
workers and finishers. Milling using this equipment represents a small
share of the overall job duties of these applicable key occupations: In
the PEA OSHA judged that 5 percent of all work for the first two
occupation groups is spent using this equipment, and OSHA is retaining
that estimate in the FEA because there were no comments challenging
that estimate. OSHA estimates that terrazzo workers use the equipment
about half as much as the other two occupation groups, so OSHA
estimates that 2.5 percent of all work time spent by terrazzo workers
and finishers will be spent using this equipment.
Rock Crushing Machine Operators and Tenders
    According to information collected from ERG communication and OSHA
SEP inspection reports, rock crushing machine operators spend most, if
not all, of their shifts at and around the rock crushing process
(Polhemus, 2000, Document ID 0958; Haney, 2001, Document ID 0721; OSHA
SEP Inspection Report 2116507, Document ID 0186; OSHA SEP Inspection
Report 300441862, Document ID 0030). OSHA estimated in the PEA that
this occupational group spends 75 percent of its time using rock
crushing machines and did not receive any comment on the estimate. OSHA
has retained this estimate for the FEA.
Tunnel Boring
    Underground workers perform both tunnel work and other types of
construction work. The majority of these underground tasks still fall
under Table 1 and have been accounted for elsewhere in the appropriate
construction task analysis. However, a small amount of silica-
generating underground construction work outside the scope of Table 1,
primarily in tunnel boring, is expected to occur. The cost of
engineering controls for this activity (to comply with the new PEL) is
presented after the total engineering control costs to comply with
Table 1 are presented.
SBREFA Panel Comments on Key and Secondary Occupations
    As stated in the comments during the Silica SBREFA process, one
SBREFA commenter was ``unable to reconcile ERG's statement that `the
amount of time . . . grinders and tuck-pointers perform grinding ranges
widely, from about 1 hour per shift up to a full 8-hour shift (or
longer)' [see the discussion on technological feasibility in Chapter IV
of the FEA] with the 2.5% estimate in Table 4-8 [in the ERG report
(2007a); Table V-26 in the PEA]'' (Document ID 0004; 1709). The
commenter also asserted that masonry cutters use stationary saws
approximately 20 to 30 percent of their working time (rather than 10
percent), and that masonry cutters use portable saws approximately 5
percent of their working time (rather than 10 percent) (Document ID
0004).
    In response, OSHA reiterated in the PEA that Table V-26 of the PEA
showed the estimates of the full-time-equivalent number of workers in
key and secondary occupations using equipment to perform silica-
generating tasks. These occupations are taken from the BLS Occupational
Employment Survey classification system and are much broader than the
``masonry cutter'' category referred to by the commenter, implying a
lower percentage of time devoted to tasks involving masonry cutting.
    OSHA did not receive further comment on this explanation.
Therefore, OSHA has not changed these estimates in the FEA. For each
occupation the estimates in Table V-37 of the FEA are meant to reflect
the typical or average amount of a worker's time (over a year) devoted
to the listed tasks.
FTE At-Risk Employment by Task Category
    Tables V-38a and V-38b of the FEA provide estimates, by occupation,
of the full-time-equivalent (FTE) number of key and secondary workers,
respectively, for each task category, using the percentages and ratios
from Table V-37 of the FEA. These tables are relatively direct
compilations from previous tables with adjustments needed, in a few
cases, to assure that the industry-specific FTE occupational totals did
not exceed the total occupational employment for any industry.
    Table V-39 of the FEA shows the corresponding estimates by NAICS
code for the construction industry.
    OSHA distributed FTE at-risk workers across NAICS codes according
to the combination of task categories and occupational (key and
secondary) categories (from BLS, 2012, Document ID 1560) derived and
updated by ERG for each industry group (ERG, 2007a, Document ID 1709).
    Overall, a full-time equivalent of 374,003 workers is estimated to
use equipment to perform work on silica-containing materials in
construction, ranging from 1,135 FTEs for rock crushing machine
operators and tenders to 198,585 FTEs for heavy equipment operators and
ground crew laborers (grading and excavating).
Total At-Risk Employment
    In the PEA, OSHA used a relatively crude approach to convert the
estimated number of FTE affected construction workers to the number at-
risk construction workers. There, OSHA used a multiplier of 2 or 5,
depending on the industry, to convert the number of FTEs to the number
of at-risk workers (in Table V-37 of the PEA).
    OSHA received several comments regarding the analysis used in the
PEA as being too simplistic. Joseph Liss challenged OSHA's methodology:

    Even though OSHA estimates the number of workers needing
training for silica exposure under the proposed rule by

multiplying full-time equivalents by a factor of either 2 or 5,
depending upon the sub-industry, the multiplicative factor for
training purposes is likely to be much higher. For example, while
paving, surfacing, and tamping operators spend a total of only 5% of
their time on tasks exposed to silica, as estimated by ERG, it is
not unlikely that many of the 51,857 workers in that industry sub-
group will do silica-exposed work at some point, and, thus, require
training. There are 823,737 construction laborers, and ERG estimated
that 3% of their time is spent on silica-exposed work, but the
severe turnover in that industry means firms may need to train many
of those workers in silica safety procedures and health effects.
OSHA estimates the nation's 575,000 residential construction workers
spend 5% of their time on construction work and uses a
multiplicative factor of two, thus assuming that only 10% of those
workers require training and exposure monitoring. Costs may increase
if the number of workers exposed increases, since OSHA requires
training for all newly hired workers as well as all initial training
for all workers exposed to silica (citations omitted) (Document ID
1950, p. 9).

    Additionally, the Construction Industry Safety Coalition (CISC)
submitted calculations to arrive at their own results of at-risk
workers. They note:

    These percentages represent our quick judgement across both the
key occupations and the secondary occupations that OSHA identifies
as participating in the crew when the at-risk task is performed. If
we had more time, we would like to make this judgement more
carefully (Document ID 4032, Tab 6).

    For the FEA, in response to comments, OSHA refined its process, as
described below, to allow for a more nuanced approach to estimating the
number of affected workers. As a result of this revised approach, the
ratio of the estimated number of at-risk construction workers to the
estimated number of FTE-affected construction workers increased from
approximately three to one in the PEA to over five to one in the FEA.
OSHA first assigned each of the affected NAICS construction industries
to one of four subsectors in order to account for likely differences
among specific industries with respect to the frequency with which
silica-generating equipment is used. These subsectors are shown in
Table V-40a of the FEA. Note that non-construction industries doing
construction work--state and local governments and electric utilities--
are included in Subsector 3.
    Second, because at-risk workers do not necessarily specialize in
jobs that use equipment that generates silica-containing dust, ERG
independently estimated the number of ``affected'' workers based on
judgments of the share of workers in each occupation that would likely
ever perform these tasks. These judgments were also made on a
subsector-by-subsector basis. In most cases, costs for program
requirements (but not for engineering controls) are based on the
numbers of affected workers performing each task in a given industry.
The estimated share of affected workers for the key occupations, taking
into account the specific construction subsector and task, is shown in
Table V-40b of the FEA.
    Using the FTE rates, secondary ratios, and affected rate parameters
displayed in Table V-37 of the FEA, OSHA calculated, in Table V-39 of
the FEA, that there are an estimated 374,003 FTEs affected by the rule.
Table V-41 of the FEA converts these FTEs to 2.02 million affected
construction workers disaggregated by occupation based on 2012 County
Business Pattern (CBP) total employment of 2.93 million in affected
occupations in construction industries. Thus, as shown in Table V-41 of
the FEA, about 68.9 percent of construction workers in affected
occupations will be affected by the final rule. Table V-42 of the FEA
shows the same estimated number of affected workers, but disaggregated
by NAICS industries and equipment category. There are an estimated
13.45 million workers total in the affected industries, meaning that
about 15 percent of the workers in these industries are affected by the
final rule. That percentage is misleading, however, because almost 7.7
million of total employment in affected industries (almost 60 percent)
are employed in state and local governments, of which only 2 percent
are affected by the final rule. When these public workers are removed,
approximately 32 percent of the construction workers in affected
private industries are affected by the final rule.
    All of the above statistics do not include the estimated 11,640 at-
risk abrasive blasters working in construction industries. Also,
because some occupations are associated with the use of more than one
equipment category, the ``affected'' totals are constrained to be less
than or equal to the industry total for each at-risk occupation.
Labor Cost and Total Value of Work Performed Using Silica Exposure-
Generating Equipment
    To derive labor costs and project value for construction work done
using the specified equipment where occupational exposure to silica is
found, OSHA multiplied the mean hourly wage, as reported by OES (BLS,
2012, Document ID 1560), for each affected occupation within each
affected industry, by 2,000 hours. Then, to derive the total value of
annual wages expended for work done using specified equipment to
perform silica exposure-generating activities, OSHA multiplied that
product by the number of affected full-time-equivalent employees. These
estimates were then inflated to adjust for fringe benefits. These
loaded-wage costs, totaled by industry and equipment category, are
summarized in Table V-43 of the FEA as the annual labor value (or labor
cost) of silica-generating projects. Overall, OSHA estimated the labor
value of all silica-generating construction work performed with the
specified equipment to be $21.8 billion annually.
    OSHA then converted the labor values for each industry and task
category from Table V-43 of the FEA to the total project value by
dividing by the labor share of project costs. This conversion is
possible because the labor share for each task category equals the
labor value divided by project value, so dividing the labor value by
the labor share generates an estimate of project value. The
corresponding estimates of total project value for each industry and
equipment category are shown in Table V-44 of the FEA. Overall, OSHA
estimated the value of silica-generating construction work performed
with the specified equipment at $41.2 billion. The values for specific
equipment categories ranged from $136.2 million for rock crushing
machine operators and tenders to $28.0 billion for heavy construction
equipment operations-II.
    The value of work performed using the specified equipment was then
summed by NAICS industry to derive the total value of at-risk projects,
a base from which OSHA calculated control costs associated with
compliance with Table 1 or the final PEL.
Aggregate Control Costs in Construction To Comply With Table 1 or the
New PEL
    For the final rule, OSHA revised Table 1 to include separate
engineering control and respirator requirements for tasks indoors or in
enclosed areas (``indoor tasks'') to provide a means of exhaust as
needed to minimize the accumulation of visible airborne dust. As a
result, indoor tasks will have an additional cost to reflect use of
control equipment (e.g., a fan or ``blower'') providing a means of
exhaust as needed to minimize the accumulation of visible airborne
dust. These additional indoor costs were included in Table V-34 of the
FEA. However, to properly reflect these costs in the aggregate control
costs in construction, OSHA had to add an additional methodological
step. OSHA's Office of Technological Feasibility

helped to develop estimates of the distribution of silica-related work
disaggregated by the type of control equipment used, the duration of
the task, and the location of the task (i.e., indoors or outdoors). The
resulting distribution of silica-related work, which is later used to
weight costs by the percentage of tasks performed indoors or outdoors,
is displayed in Table V-45 of the FEA.
    To derive estimates in Table V-46 of the FEA of aggregate
incremental compliance costs to meet final Table 1, the total value of
construction work using the specified equipment and requiring controls
(in Table V-44 of the FEA) was multiplied by the percentage of
incremental cost associated with the controls required for each
equipment category (in Tables V-36a and V-36b of the FEA), weighted by
the percentage of work using each type of equipment performed outdoors
and indoors (in Table V-45 of the FEA), and reduced by the percentage
of baseline compliance.
    As indicated in Table V-46 of the FEA, OSHA estimates that the
incremental compliance costs for engineering controls (excluding tunnel
boring and abrasive blasting) will total $386.4 million for
construction work performed using the specified equipment affected by
the final standard.
Control Costs for Construction Tasks Not Under Table 1
Abrasive Blasting
    In the PEA, OSHA estimated that some abrasive blasting crews were
not currently using all feasible engineering controls and added costs
for wet methods for them to achieve the proposed PEL. OSHA did not
receive comments on the PEA estimates of engineering control costs for
abrasive blasting crews and has retained the same methodology to
estimate costs for the FEA.
    Consistent with what was done in the PEA, Table V-47a of the FEA
presents the unit costs and analytical assumptions applied in OSHA's
cost analysis of controlling silica exposures during abrasive blasting
operations. As shown in the table, after accounting for the number of
affected workers, crew size, daily output, blasting cost per square
foot, number of blasting days per year, and the percentage of crews
using sand, OSHA estimates that baseline annual costs for sand blasting
total $126.7 million. As in the PEA, ERG estimated that the incremental
cost for wet blasting is 30 percent of baseline costs and that 50
percent of crews currently use wet methods. Therefore, the annual costs
to comply with the final standard by using wet methods during sand
blasting are expected to total $19.0 million, or $2,366 per worker for
the approximately 8,033 workers exposed to silica dust.
    Distributing these annualized costs by industry, OSHA estimates
that employers in NAICS 238200, Building Finishing Contractors, will
incur compliance costs of $12.1 million annually, while firms in NAICS
238900, Other Specialty Trade Contractors, will incur compliance costs
of $6.9 million annually.
Tunnel Boring
    Tunnel boring is not included on Table 1 of the final rule. An
employer engaged in tunnel boring must comply with the PEL of 50 [mu]g/
m\3\ specified in Sec.  1926.1153(d). Employers in tunnel boring must
already comply with the ventilation and dust suppressant requirements
in subpart S of Part 1926 (Underground construction), which would have
allowed those employers to meet the previous PEL of 250 [mu]g/m\3\.
Therefore, OSHA calculates the additional controls necessary to reduce
exposures from the preceding PEL to the new PEL of 50 [mu]g/m\3\.
    In most cases, employers are able to reduce exposures to the
preceding PEL by providing suction at the drill head, removing the dust
as soon as it is generated. The technological feasibility chapter of
the FEA demonstrates that employers can do so by extending the existing
suction controls as the drill head progresses. There are limits on
these extensions, however, and the amount of worker exposure can
increase if the suction is not extended frequently enough to keep it at
the drill head. This extension does not require additional machinery,
but it is likely to require the employer to invest more labor time to
extend the suction device more frequently to meet the new PEL than
previously necessary to meet the preceding PEL. OSHA has estimated in
Table V-47 of the FEA the control costs for tunnel boring using the
same cost methodology applied in the PEA (see Tables V-21 and V-24 in
the PEA) to calculate the incremental cost as a percentage of baseline
control costs (0.013%). The rest of the calculations in Table V-47
reflect 2012 data on the number of affected FTE tunnel workers and 2012
hourly wage rates. The resulting estimate of annualized incremental
control costs for tunnel boring is about 0.02 million.
    Table V-48 of the FEA adds the abrasive blasting and the tunnel
boring control costs in construction to the control costs for Table 1
tasks presented in Table V-46 of the FEA.
Adjustment for Self-Employed Workers on a Multi-Employer Worksite
    The OSH Act provides authority for OSHA to regulate employers for
the protection of their employees. Because sole proprietors without
employees, referred to as ``self-employed workers'' for the purposes of
this discussion, are not ``employers'' under the Act, OSHA cannot
require them to comply with the silica standard. On a multi-employer
worksite, however, their silica activities could expose employees
protected by the Act to respirable crystalline silica.
    Employers must still protect their employees from exposure to
silica in accordance with the standard, whether it is generated by work
performed by their own employees or by the work performed by a sole
proprietor not regulated by the Act (see the summary and explanation of
the written exposure control plan requirements in paragraph Sec.
1926.1153(g)(1)(iv)). Under OSHA's multi-employer citation policy (CPL
02-00-124), employers of workers who may be exposed to silica are
considered ``exposing employers'' who have a duty to protect their
employees, even from hazards they do not correct themselves. However,
the controlling employer, the employer in overall charge of the
worksite or project, also has a duty to exercise reasonable care to
prevent and detect violations of the silica standard on the multi-
employer worksite. The silica standard does not limit the means by
which either employer may fulfill this duty, and in many cases the
issue may be resolved if the work schedule does not place the self-
employed worker in the same area of the worksite at the same time as
employees, thereby avoiding the need for additional measures.
    As discussed in Chapter III of the FEA, CISC requested that the
Agency account for the costs arising from self-employed workers
separately based on the theory that self-employed workers will use the
controls necessary to comply with Table 1 to reduce exposures to others
when working on a multi-employer worksite where employees are present
(Document ID 4217, p. 80). CISC identified several reasons why this
might happen, including self-interested recognition of ``Table 1
specifications as the safe way to perform their work''; demands by
construction general contractors that anyone working on their site,
whether self-employed or not, conform to regulatory requirements; and
demands by nearby employers that their employees ``not suffer increased
silica

exposures from inappropriate practices by self-employed workers.''
    While these are not costs that OSHA typically includes in its
analysis, OSHA recognizes that Table 1 is unique among OSHA standards,
and that it is possible that controlling employers on a multi-employer
construction worksite may assume some costs of engineering controls--
either by providing the controls or by reimbursing the self-employed
persons for the costs of the controls through increased fees--when they
cannot resolve the issue through simple scheduling choices. Therefore,
OSHA is estimating the additional cost of the engineering controls in
that scenario.
    In order to estimate the number of self-employed persons in
construction, CISC's contractor, Environomics, Inc., took the following
approach:

    The U.S. Census Bureau, in Revised 2008 Nonemployer Statistics
Reflecting 2009 Methodology Changes, provides information on the
number of self-employed individuals (``nonemployers'') working in
each of the 4-digit construction industries (total of 2.52 million
self-employed construction workers), but no further information on
the occupations of these self-employed workers. In order to estimate
the number of self-employed workers in each of the various at-risk
construction occupations that OSHA identified and that we added, we
simply assumed that these 2.52 million ``nonemployers'' are
distributed among occupations within each construction NAICS in the
same proportion as employed workers are distributed among
occupations within the NAICS (Document ID 4217, p. 80).

    Note that the Census data that Environomics used provides detail on
self-employed persons by 4-digit NAICS construction industries but not
by occupation. Hence, in the absence of occupational data, Environomics
simply assumed that the number of self-employed persons by occupation
was proportional to the number of employees by occupation--which
implies that the ratio of the number of self-employed persons to
employees was the same for each occupation. Using this database and
approach, Environomics estimated that the ratio of self-employed
persons to employees for all occupations affected by the rule was 40.1
percent (1,811,009 self-employed relative to 4,519,889 employees).
Based on the full-time-equivalent (FTE) number of workers--which, in
OSHA's estimation methodology, determines the amount of engineering
control equipment used--Environomics calculated that the ratio of FTE
self-employed persons to FTE employees for all occupations affected by
the rule was 35.7 percent.
    Having reviewed the Environomics self-employment analysis, OSHA has
concluded that the occupation of the self-employed persons is a much
more relevant factor for estimating costs than the 4-digit construction
industry in which self-employed persons work. Therefore, for its
analysis, OSHA has chosen to rely on data from the 2013 BLS Current
Population Survey, with the goal of estimating the ratio of the number
of self-employed persons to the number of employees by occupation.
Table V-49 of the FEA presents data from the 2013 BLS Current
Population Survey with the focus on the ratio of the self-employed to
the non-self-employed (i.e., employees).\44\ Note that this table
includes many occupations that do not involve silica exposure (e.g.,
boilermakers, paperhangers, glaziers) and others that are not covered
by OSHA (e.g., mining machine operators; roof bolters, mining--covered
by MSHA).
---------------------------------------------------------------------------

    \44\ The absolute number of self-employed and employed in
construction by occupation from this survey is not, itself, relevant
for this analysis. What matters is the ratio of self-employed to
non-self employed in construction where the estimates of both types
of workers are derived from a single source.
---------------------------------------------------------------------------

    Table V-50 of the FEA presents the same data as shown in Table V-49
of the FEA, but restricted to just those occupations where OSHA
estimated that workers are potentially exposed to hazardous levels of
respirable crystalline silica. One thing that is immediately obvious in
this table is the very wide variation from occupation to occupation in
the ratio of the self-employed to the employed, with the ratio ranging
from 0 percent to 47.53 percent. This wide variation is clearly
incompatible with the assumption made by Environomics that the ratio of
the number of self-employed to employees is the same for all
occupations. Table V-50 of the FEA also shows that average ratio of
self-employed to employees over all construction occupations involving
silica exposure (when the ratio is allowed to vary by occupation) is
22.82 percent when weighted by the number of employees (as compared to
40.1 percent as estimated by Environomics).
    As noted above, in OSHA's methodology, the amount of engineering
control equipment used is based on the FTE number of workers. In Table
V-51 of the FEA, OSHA multiplied the FTE rate for each occupation (from
Tables V-38a and V-38b of the FEA) by the number of self-employed
workers and employees in that occupation (from Table V-48 of the FEA).
As shown in Table V-51 of the FEA, there are an estimated 69,461 FTE
self-employed workers in at-risk occupations, relative to the total of
377,913 FTE employees in at-risk occupations. In other words, the
number of at-risk FTE self-employed workers is 18.38 percent of the
number of at-risk FTE employees (as compared to 35.7 percent as
estimated by Environomics).
    The analysis of the number of self-employed persons conducted by
Environomics stopped at this point. However, as OSHA explained in
Chapter III of the FEA, self-employed workers are not required to
comply with the final rule and are only likely to do so in two
situations: (1) Where self-employed workers are generating silica dust
while working in a multi-employer construction worksite such that their
activities could expose the employees of others, and (2) where the host
employer (or competent person) is unable to schedule the self-employed
worker's activities or location so as to prevent the exposure or
overexposure of other, covered workers. OSHA does not have data on the
likelihood of either of these two conditions. OSHA judges that self-
employed workers work at multi-employer construction sites at the same
times as others a minority of their worktime, and work even less
frequently within the same area such that covered employees could be
exposed. Nevertheless, OSHA is conservatively estimating here that they
do so 50 percent of the time. OSHA also judges that the host contractor
(with the assistance of the competent person) would be able to schedule
the self-employed workers' activities or location so as to prevent the
exposure or overexposure of other, covered workers a majority of the
time. This makes sense because self-employed workers would often be
used on multi-employer sites when they possess special skills not
otherwise available onsite. Therefore, their work frequently could be
performed at a different time or location from the other work. In any
case, for costing purposes, OSHA is conservatively estimating that the
work of self-employed persons cannot be isolated in time or space so as
to prevent the exposure or overexposure of other, covered workers 50
percent of the time that those self-employed workers are on the multi-
employer worksite.
    Based on these estimates, OSHA calculates that only 25 percent of
the at-risk work of self-employed workers would meet the conditions in
which a host or controlling employer would incur engineering control
costs to mitigate the exposures to employees on the site. At the bottom
of Table V-51 of the FEA, OSHA has accordingly reduced the number of
FTE self-

employed workers using equipment to perform silica-dust-producing work
relative to the number of FTE at-risk employees to 25 percent of the
earlier estimate of 18.38 percent. OSHA therefore concludes that the
number of FTE at-risk self-employed workers imposing costs on host
employers is equal to 4.60 percent of the number of FTE at-risk
employees. This result is shown at the bottom of Table V-51 of the FEA.
    Finally, in Table VII-13, OSHA increased the estimates of the
control costs for work performed using the specified equipment in
construction presented in Table V-48 of the FEA by 4.60 percent to
include the engineering control costs that would be incurred by host or
controlling employers to control the exposures caused by self-employed
workers. This increases the annualized cost of engineering controls
needed in construction to comply with the final rule from $405.5
million to $423.4 million.

[GRAPHIC] [TIFF OMITTED] TR25MR16.053

2. Respiratory Protection
    OSHA's cost estimates assume that implementation of the recommended
silica controls prevents workers in general industry and maritime from
being exposed over the PEL in most cases. Specifically, based on its
technological feasibility analysis, OSHA expects that the engineering
controls are adequate to keep silica exposures at or below the PEL for
an alternative PEL of 100 [mu]g/m\3\ (introduced for economic analysis
purposes).\45\ For the new 50 [mu]g/m\3\ PEL, OSHA's feasibility
analysis

suggests that the controls that employers use, either because of
technical limitations or imperfect implementation, might not be
adequate in all cases to ensure that worker exposures in all affected
job categories are at or below 50 [mu]g/m\3\.
---------------------------------------------------------------------------

    \45\ As a result, OSHA expects that establishments in general
industry do not currently use respirators to comply with the current
OSHA PEL for quartz of approximately 100 [mu]g/m\3\.
---------------------------------------------------------------------------

    For the FEA, OSHA estimates that respirators will be required: (1)
For all workers that the Agency's technological feasibility analysis
has determined will require respirator use; and (2) for ten percent of
the remaining workers currently exposed above 50 [mu]g/m\3\ at covered
workplaces.
    This is a change in methodology from the PEA, where OSHA estimated
the percentage of workers requiring respirators in an industry as
either (1) or (2), whichever was larger. The Agency believes that the
FEA formula, which results in higher estimates of respirator usage, is
more accurate in that it reflects the combined effects of (1) and (2)
whereas the earlier methodology did not. The number of workers that the
FEA estimates will need respirators is presented in Table V-13 in the
FEA.
    In the PEA, OSHA concluded that all maritime workers engaged in
abrasive blasting were already required to use respirators under
existing OSHA standards and, therefore, maritime establishments would
incur no additional costs for maritime workers to use respirators as a
result of this final rule. However, for the FEA, OSHA has determined
from its earlier technological feasibility analysis that only abrasive
blasting operators, but not abrasive blasting helpers, are already
required to use respirators under existing OSHA standards. The Agency,
therefore, has added respirator costs for abrasive blaster helpers in
maritime (half of all the abrasive blaster workers) as a result of this
final rule.
    For construction, employers whose workers are exposed to respirable
silica above the proposed PEL were assumed to adopt the appropriate
task-specific engineering controls and, where required, respirators
prescribed in Table 1 and paragraph (g)(1) in the final standard.
Respirator costs in the construction industry have been adjusted to
take into account OSHA's estimate (consistent with the findings from
the NIOSH Respiratory Survey, 2003, Document ID 1492) that 56 percent
of establishments in the construction industry are already using
respirators that would be in compliance with the final silica rule.
    OSHA used respirator cost information from a 2003 OSHA respirator
study to estimate the annual cost of $367 (general industry) or $286
(construction) for disposable filtering facepiece respirators, $520
(general industry) or $409 (construction) for a half-mask, non-powered,
air-purifying respirator and $644 (general industry) or $533
(construction) per year (in 2012 dollars) for a full-face non-powered
air-purifying respirator (ERG, 2003, Document ID 1612). These unit
costs reflect the annualized cost of respirator use, including
accessories (e.g., filters), training, fit testing, and cleaning where
relevant.
    The PEA estimated that (with the exception of workers who are
entering regulated areas) all workers in general industry and
construction who need respirators with an assigned protection factor
(APF) of 10 would use non-disposable, half-face respirators. The FEA
estimates that in general industry half of the workers who need
respirators will use half-face elastomeric respirators and half will
use disposable N95 respirators. This is because, as clarified in the
final rule, both disposable and non-disposable respirators are
available with an APF of 10, and, with each type of respirator offering
certain advantages, OSHA accordingly estimates that about half of the
employees in general industry and maritime will prefer the ease of use
of disposable respirators while the other half will prefer the
durability of non-disposable respirators. For the construction sector,
the FEA estimates that 10 percent of workers needing respirators will
use elastomeric half-face respirators and 90 percent will use
disposable N95 respirators. This is because very few workers in
construction engage in tasks requiring respirator use full-time. Under
those circumstances, disposable respirators are both more convenient to
use and much less expensive than reusable respirators.
    In addition to bearing the costs associated with the provision of
respirators, employers will incur a cost burden to establish respirator
programs. OSHA projects that this expense will involve an initial 8
hours for establishments with 500 or more employees and 4 hours for all
other firms. After the first year, OSHA estimates that 20 percent of
establishments would revise their respirator program every year, with
the largest establishments (500 or more employees) expending 4 hours
for program revision, and all other employers expending 2 hours for
program revision. Consistent with the findings from the NIOSH
Respiratory Survey (2003) (Document ID 1492), OSHA estimates that 56
percent of establishments in the construction industry that would
require respirators to achieve compliance with the final PEL already
have a respirator program.\46\ OSHA further estimates that 50 percent
of firms in general industry and all maritime firms that would require
respirators to achieve compliance already have a respirator program.
---------------------------------------------------------------------------

    \46\ OSHA's derivation of the 56 percent current compliance rate
in construction, in the context of the final silica rule, is
described in Chapter V in the FEA.
---------------------------------------------------------------------------

3. Exposure Assessment
    OSHA developed separate cost estimates for (1) initial monitoring
or any exposure monitoring at hydraulic fracturing sites and (2)
scheduled monitoring at fixed sites (which excludes hydraulic
fracturing). Costs under (2) were estimated to be lower because the
exposure monitoring is expected to be of shorter duration (possibly
obviating an overnight stay) and could be conducted by a lower-cost
Industrial Hygienist (IH) or IH technician rather than by a CIH. Based
on the comments received in the record, OSHA decided to significantly
increase its estimate from $500 (in the PEA) to $2,500 for an IH
consultant to perform initial exposure monitoring or to perform at
sites that have not previously been well characterized. In the
construction sector, the $2,500 cost estimate for IH services applies
to all exposure monitoring since the worksite is not fixed and has not
been previously characterized. OSHA estimates that the IH periodic
exposure monitoring costs would be approximately $1,250, or half of the
$2,500 estimate. These IH monitoring costs would cover 2, 6, and 8
personal breathing zone (PBZ) samples per day for small, medium, and
large establishments, respectively.
    For initial monitoring or any exposure monitoring at hydraulic
fracturing sites, the total unit cost of an exposure sample is
estimated to range from $487 to $1,425 (depending on establishment
size). For periodic monitoring in general industry and maritime,
excluding hydraulic fracturing sites, the total unit cost of an
exposure sample is estimated to range from $328 to $796 (depending on
establishment size).
    Tables V-14 and V-61 in the FEA shows the unit costs and associated
assumptions used to estimate exposure assessment costs. Unit costs for
exposure sampling include direct sampling costs, the costs of
productivity losses, and recordkeeping costs, and, depending on
establishment size, range from $328 to $1,421 per sample in general
industry and maritime and from $488 to $1,425 per sample in
construction.

    For costing purposes, based on OSHA (2016), OSHA estimated that
there are four workers per work area. OSHA interpreted the initial
exposure assessment in general industry and maritime as requiring
first-year testing of at least one worker in each distinct job
classification and work area who is, or may reasonably be expected to
be, exposed to airborne concentrations of respirable crystalline silica
at or above the action level.
    For periodic monitoring, the final standard provides employers an
option of assessing employee exposures either under a performance
option (paragraph (d)(2)) or a scheduled monitoring option (paragraph
(d)(3)). For the performance option, the employer must assess the 8-
hour TWA exposure for each employee on the basis of any combination of
air monitoring data or objective data sufficient to accurately
characterize employee exposures to respirable crystalline silica. For
the scheduled monitoring option (termed the ``periodic'' monitoring
option in the proposal), the employer must perform initial monitoring
to assess the 8-hour TWA exposure for each employee on the basis of one
or more (PBZ) air samples that reflect the exposures of employees on
each shift, for each job classification, in each work area. Where
several employees perform the same job tasks on the same shift and in
the same work area, the employer may sample a representative fraction
of these employees in order to meet this requirement. In representative
sampling, the employer must sample the employee(s) who are expected to
have the highest exposure to respirable crystalline silica. Under the
scheduled monitoring option, requirements for periodic monitoring
depend on the results of initial monitoring. If the initial monitoring
indicates that employee exposures are below the action level, no
further monitoring is required. If the most recent exposure monitoring
reveals employee exposures to be at or above the action level but at or
below the PEL, the employer must repeat monitoring within six months of
the most recent monitoring. If the most recent exposure monitoring
reveals employee exposures to be above the PEL, the employer must
repeat monitoring within three months of the most recent monitoring.
OSHA used the fixed schedule option under the frequency-of-monitoring
requirements to estimate, for costing purposes, that exposure
monitoring will be conducted (a) twice a year where initial or
subsequent exposure monitoring reveals that employee exposures are at
or above the action level but at or below the PEL, and (b) four times a
year where initial or subsequent exposure monitoring reveals that
employee exposures are above the PEL.
    As required under paragraph (d)(4) of the final rule, employers
must reassess exposures whenever a change in the production, process,
control equipment, personnel, or work practices may reasonably be
expected to result in new or additional exposures at or above the
action level, or when the employer has any reason to believe that new
or additional exposures at or above the action level have occurred. In
response to comments, OSHA increased its estimate from 15 percent to 25
percent of the share of workers whose initial exposure or subsequent
monitoring was at or above the action level would undertake additional
monitoring.
    Changes from the proposed to the final rule have resulted in a
significant reduction in OSHA's estimate of the annual number of
samples taken by construction employers. For the final rule, employers
following Table 1 are not required to engage in initial or subsequent
exposure monitoring for those construction workers engaged in tasks on
Table 1. Therefore, OSHA only estimated scheduled semi-annual exposure
monitoring (for expected exposures at or above the action level but at
or below the PEL) and scheduled quarterly exposure monitoring costs
(for expected exposures above the PEL) for those operations are not
listed on Table 1. In addition, OSHA estimated that some small fraction
of employers--1 percent--will choose to conduct initial sampling to
investigate the possibility that exposures are so low (below the action
level) that Table 1 need not be followed.
    A more detailed description of unit costs, other unit parameters,
and methodological assumptions for exposure assessments is presented in
Chapter V of the FEA.
4. Medical Surveillance
    Paragraph (i) of the final standard requires the employer to make
medical surveillance available for each employee occupationally exposed
to respirable crystalline silica at or above the action level of 25
[mu]g/m\3\ for 30 days or more per year. ERG (2013) assembled
information on representative unit costs for initial and periodic
medical surveillance (Document ID 1712). Separate costs were estimated
for current employees and for new hires as a function of the employment
size (i.e., 1-19, 20-499, or 500+ employees) of affected
establishments. Table V-16 in the FEA presents ERG's unit cost data and
modeling assumptions used by OSHA to estimate medical surveillance
costs.
    In accordance with paragraph (i)(2) of the final standard, the
initial medical examination will consist of (1) a medical and work
history, (2) a physical examination with special emphasis on the
respiratory system, (3) a chest x-ray interpreted and classified
according to the International Labour Office (ILO) International
Classification of Radiographs of Pneumoconiosis by a NIOSH-certified B
Reader, (4) a pulmonary function test administered by a spirometry
technician with a current certificate from a NIOSH-approved course, (5)
testing for latent tuberculosis (TB) infection, and (6) any other tests
deemed appropriate by the PLHCP. In accordance with paragraph (i)(3) of
the final standard, the contents of the periodic medical examinations
are the same as those for the initial examination, with the exception
that testing for latent tuberculosis infection is not required.
    As shown in Table V-16 in the FEA, the estimated unit cost of the
initial health screening for current employees in general industry and
maritime ranges from approximately $415 to $435 and includes direct
medical costs, the opportunity cost of worker time (i.e., lost work
time, evaluated at the worker's 2012 hourly wage, including fringe
benefits) for offsite travel and for the initial health screening
itself, and recordkeeping costs. The variation in the unit cost of the
initial health screening is due entirely to differences in the
percentage of workers expected to travel offsite for the health
screening. In OSHA's experience, the larger the establishment the more
likely it is that the selected PLHCP would provide the health screening
services at the establishment's worksite. OSHA estimates that 20
percent of establishments with fewer than 20 employees, 75 percent of
establishments with 20-499 employees, and 100 percent of establishments
with 500 or more employees would have the initial health screening for
current employees conducted onsite.
    The unit cost components of the initial health screening for new
hires in general industry and maritime are identical to those for
existing employees with the exception that the percentage of workers
expected to travel offsite for the health screening would be somewhat
larger (due to fewer workers being screened annually, in the case of
new hires, and therefore yielding fewer economies of onsite screening).
OSHA estimates that 10 percent of establishments with fewer than 20

employees, 50 percent of establishments with 20-499 employees, and 90
percent of establishments with 500 or more employees would have the
initial health screening for new hires conducted onsite. As shown in
Table V-16 in the FEA, the estimated unit cost of the initial health
screening for new hires in general industry and maritime ranges from
approximately $417 to $437.
    The unit costs of medical surveillance in construction were derived
using identical methods. As shown in Table V-63 of the FEA, the
estimated unit costs of the initial health screening for current
employees in construction range from approximately $429 to $467; the
estimated unit costs of the initial health screening for new hires in
construction range from $433 to $471.
    In accordance with paragraph (h)(2) of the final standard, the
initial medical examination will consist of (1) a medical and work
history, (2) a physical examination with special emphasis on the
respiratory system, (3) a chest x-ray interpreted and classified
according to the International Labour Office (ILO) International
Classification of Radiographs of Pneumoconioses by a NIOSH-certified B
Reader, (4) a pulmonary function test administered by a spirometry
technician with a current certificate from a NIOSH approved course, (5)
testing for latent tuberculosis (TB) infection, and (6) any other tests
deemed appropriate by the physician or licensed health care
professional (PLHCP). In accordance with paragraph (h)(3) of the final
standard, the contents of the periodic medical examinations are the
same as those for the initial examination, with the exception that
testing for latent tuberculosis infection is not required.
    The estimated unit cost of periodic health screening also includes
direct medical costs, the opportunity cost of worker time, and
recordkeeping costs. As shown in Table V-16 in the FEA, these triennial
unit costs in general industry and maritime vary from $415 to $435. For
construction, as shown in Table V-63 in the FEA, the triennial unit
costs for periodic health screening vary from roughly $429 to $467. The
variation in the unit cost (with or without the chest x-ray and
pulmonary function test) is due entirely to differences in the
percentage of workers expected to travel offsite for the periodic
health screening. OSHA estimated that the share of workers traveling
offsite, as a function of establishment size, would be the same for the
periodic health screening as for the initial health screening for
existing employees.
    OSHA estimated a turnover rate of 75 percent in general industry
and maritime and 40 percent in construction, based on estimates of the
separations rate (layoffs, quits, and retirements) provided by the
Bureau of Labor Statistics (BLS, 2012). However, not all new hires
would require initial medical testing. As specified in paragraph (h)(2)
of the final rule, employees who had received a medical examination
that meets the requirements of this section within the previous three
years would be exempt from undergoing a second ``initial'' medical
examination. OSHA estimates that 25 percent of new hires in general
industry and maritime and 60 percent of new hires in construction would
be exempt from the initial medical examination.
    Although OSHA believes that some affected establishments in
construction currently provide some medical testing to their silica-
exposed employees, there was significant testimony in the record that
many employers would at least have to make changes to their existing
practices in order to comply with the new standard. Therefore, for
costing purposes, the Agency assumed no current compliance with the
health screening requirements of the rule.
    OSHA requested information from interested parties on the current
levels and the comprehensiveness of health screening in general
industry, maritime, and construction. Although testimony in the record
indicated that current medical surveillance programs exist to a limited
extent among affected employers (see Chapter V, Costs of Compliance)
for costing purposes for the rule, OSHA has conservatively assumed no
current compliance with the health screening requirements.
    Finally, OSHA estimated the unit cost of a medical examination by a
pulmonary specialist for those employees found to have signs or
symptoms of silica-related disease or are otherwise referred by the
PLHCP. OSHA estimates that a medical examination by a pulmonary
specialist costs approximately $335 for workers in general industry and
maritime and $364 for workers in construction. This cost includes
direct medical costs, the opportunity cost of worker time, and
recordkeeping costs. In all cases, OSHA anticipates that the worker
will travel offsite to receive the medical examination by a pulmonary
specialist (see Chapter V in the FEA for a full discussion of OSHA's
analysis of medical surveillance costs under the final standard).
5. Familiarization Costs and Costs of Communication of Silica Hazards
to Employees
    OSHA did not estimate any employer familiarization costs in the PEA
in support of the proposed rule. OSHA's rationale for not including
familiarization costs in the PEA was that there was already an existing
silica standard in place and, therefore, the Agency expected that any
familiarization costs for a revised silica standard would be
negligible.
    However, several commenters on the proposed rule argued that
employers will need to spend time to become familiar with the
requirements of the final rule; that the employer time spent is the
direct result of the final rule itself; and, therefore, that OSHA
should include employer familiarization costs as part of the costs of
the final rule.
    OSHA found the comments in support of including some
familiarization costs persuasive and the Agency has now concluded that
employers will need to spend some time to understand the ancillary
provisions and the other new and revised components of the final rule
and to determine what actions they must take in order to comply. OSHA
estimated that 8 hours would be spent on familiarization in its 2012
update to the Hazard Communication Standard (see 77 FR 17637-17638
(March 26, 2012)) and believes that this is a reasonable estimate of
familiarization time for a typical firm for this final silica rule.
    For the silica rule OSHA used the number of employees as a proxy
for the level of familiarization that would be needed. Accordingly,
OSHA has reduced the average of 8 hours of familiarization time for
establishments with fewer employees and increased it significantly for
establishments with a larger number of employees: 4 hours per covered
employer with fewer than 20 employees; 8 hours per covered employer
with 20 to 499 employees; and 40 hours per covered employer with 500 or
more employees. These estimates represent average familiarization
times; it is expected that some establishments will spend less time on
familiarization than estimated here (e.g.,, if worker exposure never
meets or exceeds the action level) and some will spend more time on
familiarization than estimated here. The annualized costs per
establishment range from $19 to $189 for establishments in general
industry and maritime and from $21 to $207 for establishments in
construction.
    The final standard requires two forms of hazard communication to
employees: Paragraph (j)(1) notes that employers

must include respirable crystalline silica in their existing hazard
communication programs required by the hazard communication standard
(HCS) (29 CFR 1910.1200), and paragraph (j)(3) requires that employers
must provide employees with specific information and training. As
specified in paragraph (j)(3)(i) of the final rule and the HCS,
training is required for all employees in general industry and maritime
are covered by the standard. This requirement applies to newly hired
workers who would require training before starting work, workers who
change jobs within their current workplace or are assigned new tasks or
exposure protection, and any covered worker an employer believes needs
additional training. Thus OSHA has estimated a one-time training cost
for existing employees as well as recurring training costs to account
for new hires.
    OSHA estimated separate costs for initial training of current
employees and for training new hires. Given that new-hire training
might need to be performed frequently during the year, OSHA estimated a
smaller class size for new hires. OSHA anticipates that training, in
accordance with the requirements of the final rule, will be conducted
by in-house safety or supervisory staff with the use of training
modules or videos and will last, on average, one hour. OSHA judged that
establishments could purchase sufficient training materials at an
average cost of $2.10 per worker, encompassing the cost of handouts,
video presentations, and training manuals and exercises. Included in
the cost estimates for training are the value of worker and trainer
time as measured by 2012 hourly wage rates (to include fringe
benefits). OSHA also developed estimates of average class sizes as a
function of establishment size. For initial training, OSHA estimated an
average class size of 5 workers for establishments with fewer than 20
employees, 10 workers for establishments with 20 to 499 employees, and
20 workers for establishments with 500 or more employees. For new hire
training, OSHA estimated an average class size of 2 workers for
establishments with fewer than 20 employees, 5 workers for
establishments with 20 to 499 employees, and 10 workers for
establishments with 500 or more employees.
    The unit costs of training are presented in Tables V-22 (for
general industry/maritime) and V-69 (for construction) in the FEA.
Based on ERG's work, OSHA estimated the annualized cost (annualized
over 10 years) of initial training per current employee at between
$3.39 and $4.10 and the annual cost of new-hire training at between
$30.90 and $47.05 per employee in general industry and maritime,
depending on establishment size. For construction, OSHA estimated the
annualized cost of initial training per employee at between $4.21 and
$4.99 and the annual cost of new hire training at between $38.14 and
$55.76 per employee, depending on establishment size.
    OSHA recognizes that many affected establishments currently provide
training on the hazards of respirable crystalline silica in the
workplace. In the PEA OSHA estimated that 50 percent of affected
establishments already provide such training. However, some of the
training specified in the final rule requires that workers be familiar
with the training and medical surveillance provisions in the rule.
    The Agency reviewed its baseline training estimates in light of
comments in the record decided to take a more conservative approach to
estimating current compliance with the training provisions in the final
rule. Therefore, for the FEA, OSHA assumed no baseline respirable
crystalline silica training (other than that already required under the
HCS) and that a full hour of training, on average, will be required for
all covered workers. This removal of baseline respirable crystalline
silica training in estimating training costs has the effect, by itself,
of increasing the effective training costs in the FEA relative to the
PEA by 33 percent (from an average training time, per employee, of 45
minutes to 60 minutes). OSHA recognizes that this change may lead to an
overestimation of training costs for some employers.
6. Regulated Areas
    Paragraph (e)(1) of the final standard requires employers in
general industry and maritime to establish a regulated area wherever an
employee's exposure to airborne concentrations of respirable
crystalline silica is, or can reasonably be expected to be, in excess
of the PEL. Paragraph (e)(2)(i) requires employers to demarcate
regulated areas from the rest of the workplace in a manner that
minimizes the number of employees exposed to respirable crystalline
silica within the regulated area. Paragraph (e)(2)(ii) requires
employers to post signs at all entrances to regulated areas bear the
legend specified in paragraph (j)(2) of the standard. Under paragraph
(e)(3), employers must limit access to regulated areas and under
paragraph (e)(4), employers must provide each employee and designated
employee representative entering a regulated area with an appropriate
respirator (in accordance with paragraph (g) of the standard) and
require each employee and designated employee representative to use the
respirator while in a regulated area.
    Based on OSHA (2016), OSHA derived unit cost estimates for
establishing and maintaining regulated areas to comply with these
requirements and estimated that one area would be necessary for every
eight workers in general industry and maritime exposed above the PEL.
Planning time for a regulated area is estimated to be an initial seven
hours of supervisor time (initial cost of $282.67 in 2012 dollars), and
one hour for changes annually (at a cost of $40.38 in 2012 dollars);
material costs for signs and boundary markers (annualized at $66.93 in
2012 dollars); and costs of $526 annually for two disposable
respirators per day to be used by authorized persons (other than those
who regularly work in the regulated area) who might need to enter the
area in the course of their job duties. Tables V-25 in the FEA shows
the cost assumptions and unit costs applied in OSHA's cost model for
regulated areas in general industry and maritime. Overall, OSHA
estimates that each regulated area would, on average, cost employers
$666 annually in general industry and maritime.
7. Written Exposure Control Plans
    A written exposure control plan provision was not included in the
silica proposal, and no costs for a written exposure control plan were
estimated in the PEA. Paragraph (f)(2) in the final standard for
general industry and paragraph (g) in the final standard for
construction specify the following requirements for a written exposure
control plan: (i) A description of the tasks in the workplace that
involve exposure to respirable crystalline silica; (ii) a description
of the engineering controls, work practices, and respiratory protection
used to limit employee exposure to respirable crystalline silica for
each task; (iii) a description of the housekeeping measures used to
limit employee exposure to respirable crystalline silica; and (iv) for
construction, a description of the procedures used to restrict access
to work areas, when necessary, to minimize the number of employees
exposed to respirable crystalline silica and their level of exposure,
including exposures generated by other employers or sole proprietors.
    In the FEA, Table V-27 shows the unit costs and assumptions for
written exposure control plans in general

industry and Tables V-72 and V-74 show, respectively the unit costs for
developing and implementing written exposure control plans in
construction.
    Unit costs for a written exposure control plan were calculated
based on establishment size, and the Agency assumed, for costing
purposes, that a supervisor will develop and update the written
exposure control plan for each establishment, spending 1 hour for
establishments with fewer than 20 employees, 4 hours for those
establishments with between 20 and 499 employees, and 16 hours for
those establishments with 500 or more employees. OSHA estimated that 1
hour would be sufficient for very small establishments because there
is, on average, barely more than 1 worker covered by the standard per
very small establishment in general industry and maritime.
    OSHA further determined that the additional supervisory time needed
to review and evaluate the effectiveness of the plan, and to update it
as necessary, will also vary by establishment size. OSHA estimated 0.5
hours for establishments with fewer than 20 employees, 2 hours for
those with between 20 and 499 employees, and 8 hours for those with 500
or more employees to perform the annual review and update. The Agency
expects that no other labor or materials will be required to implement
the plan, so the sole cost for this provision is the time it will take
to develop, review, and update the plan.
    In the context of general industry or maritime activities in
permanent facilities, the implementation of the written exposure
control plan will not typically involve significant time or effort
above existing operations. In construction, however, employers may be
faced with new costs to implement the written exposure plan as they
move from site to site. OSHA has therefore included costs for
implementation, in addition to the costs for development of the plan,
for construction activities. The plan must be implemented by a
``competent person,'' and OSHA has addressed the additional costs for
training the competent person after the discussion of the general
implementation costs.
    Paragraph (g)(4) requires the employer to designate a competent
person to implement the exposure control plan, and restrict access to
work areas, when necessary, to minimize the number of employees exposed
to respirable crystalline silica and their level of exposure, including
exposures generated by other employers or sole proprietors. The
competent person has two broad options to restrict access to work areas
when necessary: (1) Notifying or briefing employees, or (2) direct
access control. The direct access control component is similar to the
written access control plan included in the PEA, which OSHA has
replaced with the written exposure control plan in the final rule.
While the requirements for the written exposure control plan are more
performance-oriented and thus should provide more flexibility for
employers and reduce the cost of compliance, OSHA has estimated the
costs of these options using, where appropriate, comparable components
of the regulated area and written access control plan costs estimated
in the PEA.
    For the employee notification or briefing option, OSHA estimated
that, on average, it will take the competent person 15 minutes (0.25
hours) per job to revise the briefing plan, that each job will last 10
work-days, and that there are 150 construction working days in a year
(Document ID 1709, p. 4-6). OSHA further estimated that it will take
the competent person 6 minutes (0.1 hours) to brief each at-risk crew
member (where an at-risk crew member could be an employee, a
contractor, a subcontractor, or other worker under the control of the
competent person) and that each crew consists of 4 at-risk workers. As
shown in Table V-74 in the FEA, the annual cost of the job briefing
option is $105.25 per at-risk crew member.
    For the direct access control option, OSHA estimated that, on
average, it will take the competent person 15 minutes (0.25 hours) per
job to revise the plan concerning direct access control and, again,
that each job will last 10 work-days and that there are 150
construction working days in a year. Thus, OSHA estimates that, on
average, each employer would implement a direct access control 15 times
per year over a total of 3.75 hours per year.
    OSHA also added the cost of signage and tape for constructing
physical barriers: 100 feet of hazard tape (per job) and three warning
signs. These costs are all displayed in Table V-74 in the FEA. As also
shown there, the annualized cost of the direct access control option is
$71.40 per at-risk crew member.
    As discussed in the Summary and Explanation section of this
preamble concerning the written exposure control plan, restricting
access is necessary where respirator use is required under Table 1 or
when an exposure assessment reveals that exposures are in excess of the
PEL, or in other situations identified by the competent person. On the
other hand, when exposure to respirable crystalline silica is being
successfully contained by engineering controls and work practices
specified in Table 1 and no respirator use is required by Table 1,
implementation of access control procedures is not required.
    OSHA assumed that, in restricting access, half the time employers
would use the briefing option and the other half of the time they would
use direct access control. Consequently, as shown in Table V-74, the
annualized cost of restricting access to work areas is $88.33 per at-
risk crew member.
    As specified in paragraph (g)(4) of the final standard, a competent
person must carry out the responsibilities of implementing the written
exposure control plan. As defined in the standard, ``competent person''
means an individual who is capable of identifying existing and
foreseeable respirable crystalline silica hazards in the workplace and
who has authorization to take prompt corrective measures to eliminate
or minimize them, as well as has the knowledge and ability necessary to
fulfill the responsibilities set forth in paragraph (g) of the
standard. OSHA has utilized the competent person provision in other
construction standards, such as 1926.1127, Cadmium, and 1926.1101,
Asbestos, so the Agency expects that there is widespread familiarity
with both the concept and the responsibilities of competent person in
the construction sector. As in other OSHA construction rules, a major
purpose of the competent person provision in this final silica standard
is to identify who has the responsibility for inspections of the job
sites, materials, and equipment. Thus, OSHA expects that most employers
will have training programs in place to produce competent persons, and
the cost of training someone will only be a relatively small marginal
increase in the overall training cost. For that reason, the Agency
expects that many employees designated as competent persons will
undergo some training for the position. OSHA is estimating that each
competent person will, on average, undergo two hours of training--in
addition to the one hour of silica training estimated for all
construction employees. OSHA does not anticipate any additional costs
beyond training costs to be associated with the requirement that a
competent person implement the written exposure control plan.
    While the competent person provision does not specify a training
requirement, the competent person is required to possess the knowledge
and skills to perform the functions required by the standard. For that
reason, the Agency expects that many employees designated as competent
persons will undergo some training for the position.

OSHA estimates that, on average, there will be 1 competent person for
each establishment with fewer than 20 employees, 5 competent persons
for each establishment with 20-499 employees, and 10 competent persons
for each establishment with 500 or more employees.
    OSHA expects that competent persons will be trained by a
supervisor, presumably one who went through the process to become
familiar with the requirements of the respirable crystalline silica
standard, or by a combination of supervisory and/or technical staff
that are familiar with the operation of the engineering controls. While
the competent persons are not required to be supervisors and some of
the staff providing the training may not be supervisors, OSHA is using
a supervisor's wage to estimate the costs for time spent by both the
trainers and the trainees in order to provide the upper cost limit,
realizing that the cost for establishments who do not designate
supervisors as the competent person will be lower. OSHA estimated that
the total cost per establishment to train a competent person in
construction will range from $21 to $114 (see Chapter V in the FEA for
a full discussion of OSHA's analysis of costs for written exposure
control plans under the final standard).
8. Combined General Industry/Maritime Control, Respirator, and Program
Costs
    Table VII-14 shows that the estimated combined costs for employers
in the general industry and maritime sectors to comply with the final
silica rule are approximately $370.8 million annually. These costs
include $238.1 million annually for engineering controls and $10.5
million annually for respirators to meet the final PEL of 50 [mu]g/
m\3\. The remaining $122.2 million annually are to meet the ancillary
provisions of the final rule. These ancillary annual costs consist of
$79.6 million for exposure monitoring; $29.7 million for medical
surveillance; $6.0 million for familiarization and training; $2.6
million for regulated areas; and $4.1 million for the written exposure
control plan.
    Table V-B-1 in Appendix V-B in the FEA presents estimated
compliance costs by NAICS industry code and program element for small
business entities (as defined by the Small Business Act and the Small
Business Administration's implementing regulations; see 15 U.S.C. 632
and 13 CFR 121.201) in general industry and maritime, while Table V-B-2
in the FEA presents estimated compliance costs, by NAICS code and
program element, for very small entities (fewer than twenty employees)
in general industry and maritime.
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9. Combined Construction Control, Respirator, and Program Costs
    Table VII-15 summarizes the engineering control costs, respirator
costs, and program costs of the rule for the construction sector.
Annualized compliance costs in construction are expected to total
$659.0 million, of which $423.4 million are for engineering controls,
$22.4 million are for respirators, and $213.2 million are to meet the
ancillary provisions of the rule. These ancillary annual costs consist
of $16.5 million for exposure monitoring; $66.7 million for medical
surveillance; $89.9 million for familiarization and

training; and $40.1 million for the written exposure control plan.
    Table V-B-1 in Appendix V-B in the FEA presents estimated
compliance costs by NAICS industry code and program element for small
entities (as defined by the Small Business Administration) in
construction, while Table V-B-2 in the FEA presents estimated
compliance costs, by NAICS code and program element, for very small
entities (fewer than twenty employees) in construction.
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BILLING CODE 4510-26-C
10. Total Cost Summary
    As shown in Table VII-16, annualized compliance costs associated
with the rule are expected to total $1,030 million. Table VII-16 also
provides total annualized costs for general industry, maritime, and
construction separately, by major provision or program element included
in the rule. This table shows that engineering control costs represent
64 percent of the costs of the standard for all three affected industry
sectors: general industry, maritime, and construction. Considering
other leading cost categories, costs for exposure assessment and
medical surveillance represent, respectively, 30 percent and 15 percent
of the costs of the standard for general industry and maritime; costs
for training and familiarization and medical surveillance represent,
respectively, 14 percent and 10 percent of the costs of the standard
for construction.
    While the costs presented here represent the Agency's best estimate
of the costs to industry of complying with the rule under static
conditions (that is, using existing technology and the current
deployment of workers), OSHA recognizes that actual costs could be
somewhat higher or lower, depending on the Agency's possible
overestimation or underestimation of various cost factors. In Chapter
VII of the FEA, OSHA provides a sensitivity analysis of its cost
estimates by modifying certain critical unit cost factors. Beyond this
sensitivity analysis, OSHA notes that its cost estimates do not reflect
the possibility that, in response to the rule, industry may find ways
to reduce compliance costs.
    This could be achieved in three ways. First, in construction, 36
percent of the estimated costs of the rule (all costs except
engineering controls) vary directly with the number of workers exposed
to silica. However, as shown in Table III-5 in the FEA, more than five
times as many construction workers will be affected by the rule as will
the number of full-time-equivalent construction workers necessary to do
the work. This is because most construction workers currently doing
work involving silica exposure perform such tasks for only a portion of
their workday. In response to the rule, many employers are likely to
assign work so that fewer construction workers perform tasks involving
silica exposure; correspondingly, construction work involving silica
exposure will tend to become a full-time job for some construction
workers.\47\ Were this approach fully implemented in construction, the
actual cost of the rule would decline because employers would have to
comply with the ancillary provisions of the final rule for fewer
workers.\48\ However, these workers would be subject to the full
protections of the final rule.
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    \47\ There are numerous instances of job reassignments and job
specialties arising in response to OSHA regulation. For example,
asbestos removal and confined space work in construction have become
activities performed by well-trained specialized employees, not
general laborers (whose only responsibility is to identify the
presence of asbestos or a confined space situation and then to
notify the appropriate specialist).
    \48\ OSHA expects that such a structural change in construction
work assignments would not have a significant effect on the benefits
of the rule. As discussed in Chapter VII of this PEA, the estimated
benefits of the rule are relatively insensitive to changes in
average occupational tenure or how total silica exposure in an
industry is distributed among individual workers.
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    Second, industry could demonstrate that certain construction
activities result in exposures below the action level under any
foreseeable conditions--in which case, workers engaged only in those
silica-generating activities would not be subject to the requirements
of the final rule. For example, an employer could make this
demonstration by using objective data developed for short-term,
intermittent tasks involving limited generation of silica dust. In
estimating the costs for this final rule, however, OSHA included all
costs, including ancillary costs as appropriate, associated with short-
term intermittent silica tasks.
    Third, the costs presented here do not take into account the
possible development and dissemination of cost-reducing compliance
technology in response to the rule.\49\ One possible example is the
development of safe substitutes for silica sand in activities such as
abrasive blasting operations, repair and replacement of refractory
materials, foundry operations, and in the railroad transportation
industry. Another is expanded use of automated processes which would
allow workers to be isolated from the points of operation that involve
silica exposure (such as tasks between the furnace and the pouring
machine in foundries and at sand transfer stations in structural clay
production facilities). Yet another example is the further development
and use of bags with valves that seal effectively when filled, thereby
preventing product leakage and worker exposure (for example, in mineral
processing and concrete products industries). Probably the most
pervasive and significant technological advances, however, will likely
come from the integration of compliant control technology into standard
production equipment. Such advances would both increase the
effectiveness and reduce the costs of silica controls when compared to
retrofitted production equipment. Possible examples include local
exhaust ventilation (LEV) systems attached to portable tools used by
grinders and tuckpointers; enclosed operator cabs equipped with air
filtration and air conditioning in industries that mechanically
transfer silica or silica-containing materials; and machine-integrated
wet dust suppression systems used, for example, in road milling
operations.\50\
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    \49\ Evidence of such technological responses to regulation
includes Ashford, Ayers, and Stone (1985)(Document ID 0536), OTA
(1995)(Document ID 0947), and OSHA's regulatory reviews of existing
standards under Sec.  610 of the Regulatory Flexibility Act (``610
lookback reviews''). On the other hand, 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] finds that OSHA does not systematically overestimate
costs on a per-unit basis. Nevertheless, several examples of OSHA's
overestimation of costs reported in the article are due to
technological improvements.
    \50\ A dramatic example from OSHA's 610 lookback review of its
1984 ethylene oxide (EtO) standard is the use of EtO as a sterilant.
OSHA estimated the costs of then existing add-on controls for EtO
sterilization, but in response to the standard, improved EtO
sterilizers with built-in controls were developed and widely
disseminated at about half the cost of the equipment with add-on
controls. (See OSHA, 2005.) Lower-cost EtO sterilizers with built-in
controls did not exist, and their development had not been predicted
by OSHA, at the time the final rule was published in 1984.
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    OSHA has decided not to include in its analysis any possible cost-
reducing technological advances or worker specialization because the
technological and economic feasibility of the rule can easily be
demonstrated using existing technology and employment patterns.
However, OSHA believes that actual costs, which will incorporate any
future developments of this type, will likely be lower than those
estimated here.
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a. Costs Under Alternative PEL (100 [mu]g/m\3\) Scenario
    Appendix V-C in the FEA presents, for analytical purposes, costs
for an alternative PEL of 100 [mu]g/m\3\. Total annualized compliance
costs under this alternative are $649.3 million. Table V-C-1 displays
costs for general industry, maritime, and construction by each program
element. Table V-C-2 shows total costs by NAICS industry code for all
affected general industry and maritime establishments, for business
entities in general industry and maritime defined as small by the Small
Business Administration, and for very small business entities in
general industry and maritime (those with fewer than twenty employees).
Table V-C-3 shows total costs by NAICS industry code for all affected
construction establishments, for business entities in construction
defined as small by the Small Business Administration, and for very
small business entities in construction (those with fewer than twenty
employees).
b. Costs Under Alternative Discount Rates
    An appropriate discount rate \51\ is needed to reflect the timing
of costs after the rule takes effect and to allow conversion to an
equivalent steady stream of annualized costs.
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    \51\ Here and elsewhere throughout the FEA, unless otherwise
noted, the term ``discount rate'' always refers to the real discount
rate--that is, the discount rate net of any inflationary effects.
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c. Alternative Discount Rates for Annualizing Costs
    Following OMB (2003) guidelines (Document ID 1493), OSHA has
estimated the annualized costs of the rule using separate discount
rates of 3 percent and 7 percent. Consistent with the Agency's own
practices in recent proposed and final rules,\52\ OSHA has also
estimated, for benchmarking purposes, undiscounted costs--that is,
costs using a zero percent discount rate.
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    \52\ See, for example, 71 FR 10099, the preamble for the final
hexavalent chromium rule.
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d. Summary of Annualized Costs Under Alternative Discount Rates
    In addition to using a 3 percent discount rate in its main cost
analysis, OSHA estimated compliance costs, in Appendix V-D in the FEA,
using alternative discount rates of 7 percent and zero percent. Table
V-D-1 and V-D-2 in Appendix V-D present total costs at a 7 percent
discount rate for both (1) all employers by major industry category and
program element, and (2) affected employers by NAICS industry code and
employment size class (all establishments, small entities, and very
small entities). Tables V-D-3 and V-D-4 present the same breakdowns of
total costs estimated at a zero percent discount rate.
    As shown in Appendix V-D, the choice of discount rate has only a
minor effect on total annualized compliance costs, with annualized
costs increasing from 1,030 million using a three percent discount rate
to $1,056 million using a seven percent discount rate, and decreasing
to $1,012 million using a zero percent discount rate.
e. Time Distribution of Costs
    OSHA analyzed the stream of (unannualized) compliance costs, by
industry sector, for the first ten years after the rule takes effect
under the simplifying assumption that no provisions of the rule are
phased in. As shown in Table VII-16, total compliance costs are
expected to peak in Year 1 at more than $1.5 billion. After that, costs
are estimated to decline and remain relatively flat after the initial
set of capital and program start-up expenditures has been incurred.
Costs are projected to rise somewhat in Year 4 as a result of the
triennial medical examinations and in Year 6 because of a second cycle
of control equipment purchases in construction for short-term,
intermittent work. Thereafter there are fluctuations but no strong
trend. OSHA notes that the differences between costs for Year 1 and
costs for subsequent years are narrower than might otherwise be the
case due to (1) the expectation that, in the construction sector, a
large percentage of control equipment will be rented (leading to
constant annual expenses for the rented control equipment) rather than
purchased as capital in Year 1; and (2) the expectation that the only
engineering controls needed in the maritime sector will be wet methods,
which do not require capital expenditures. On the other hand, the
ancillary provisions are expected to have a relatively large number of
initial costs (mainly labor rather than capital) in Year 1.

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F. Economic Feasibility Analysis and Regulatory Flexibility
Determination

    Chapter VI of the FEA presents OSHA's analysis of the economic
impacts of its final silica rule on affected employers in general
industry, maritime, and construction. The discussion below summarizes
the findings in that chapter.
    As a first step, the Agency explains its approach for achieving the
two major objectives of its economic impact analysis: (1) To establish
whether the final rule is economically feasible for all affected
industries, and (2) to determine if the Agency can certify that the
final rule will not have a significant economic impact on a substantial
number of small entities. Next, this approach is applied to industries
with affected employers in general industry and maritime and then to
industries with affected employers in construction. Finally, OSHA
examines the employment effects of the silica rule. This includes a