95%
                                                                            95%
                                                                            95%
                                                                            85%
                                                                            95%
                                                                            95%
                                                                            95%
Average ATI Reduction (%) [c]
                                                                           1.3%
                                                                           1.4%
                                                                           1.4%
                                                                           1.4%
                                                                           1.3%
                                                                           1.4%
                                                                           1.4%
                                                                           1.4%
Weight Reduction (pounds)
Weight [b]

Notes:
A blank cell indicates a zero value
[a]:  The majority of short box trailers are 28 feet in length.  We recognize that they are often operated in tandem, which limits the technologies that can be applied (for example, boat tails). We propose standards assuming these shorter trailers were run solo, but projected smaller aerodynamic improvements compared to improvements to long box trailers with similar technologies to reflect their frequent tandem operation.
[b]: Combines projected adoption rates with performance levels shown in Table IV-8
[c]: This set of proposed adoption rates did not apply any assumed weight reduction to meet the proposed standards for these trailers
Non-aero box trailers, with two or more work-related special components, and non-box trailers are not shown in the tables above.  We are proposing that manufacturers of these trailers meet design-based (i.e., technology-based) standards, instead of performance-based standards that would apply to other trailers.  That is, manufacturers of these trailers would not need to use aerodynamic technologies, but they would need to use appropriate lower rolling resistance tires and ATI systems, based on our assessments of the typical CO2 and fuel consumptions performance of this equipment (See Section IV.2.c).  Thus, we are projecting 100 percent adoption rates of these technologies at each stage of the program.  Compared to manufacturers that needed aerodynamic technologies to comply, the approach for non-aero box trailers and non-box trailers would result in a significantly lower compliance burden for manufacturers by reducing the amount of tracking and eliminating the need to run GEM (see Section  IV. F. ) The agencies are proposing these design standards in two stages.  In 2018, the proposed standards would require manufacturers to use tires meeting a rolling resistance of Level 1 or better and to install ATI systems on all non-box and non-aero box trailers.  In 2024, the proposed standards would require manufacturers to use LRR tires at a Level 2 or better, and to still install ATI systems.  We seek comment on all aspects of this design-based standards concept.   We also seek comment on providing manufacturers with the option of adopting Level 2 tires in the early years of the program (MY 2018-2023) and avoiding the use of ATI systems if they chose.
Table IV-15:  Projected Adoption Rates and Average Performance Parameters for Non-Aero Box and Non-Box Trailers
TECHNOLOGY
                                 NON-AERO BOX
                            & NON-BOX TRAILERS
Model Year
                                     2018
                                     2021
                                     2024
                                     2027
Aerodynamic Technologies
Bin I
                                                                           100%
                                                                           100%
                                                                           100%
                                                                           100%
Bin II

Bin III

Bin IV

Bin V

Bin VI

Bin VII

Bin VIII

Average Delta CDA (m[2]) [a]
                                                                            0.0
                                                                            0.0
                                                                            0.0
                                                                            0.0
Trailer Tire Rolling Resistance
Baseline tires

Level 1 tires
                                                                           100%
                                                                           100%

Level 2 tires
                                                                           100%
                                                                           100%
Average CRR (kg/ton) [a]
                                                                            5.1
                                                                            5.1
                                                                            4.7
                                                                            4.7
Tire Inflation System
ATI
                                                                           100%
                                                                           100%
                                                                           100%
                                                                           100%
Average ATI Reduction (%) [a]
                                                                           1.5%
                                                                           1.5%
                                                                           1.5%
                                                                           1.5%
Weight Reduction (pounds)
Weight [b]

             Notes:
             A blank cell indicates a zero value
             [a]: Combines projected adoption rates with performance levels shown in Table IV-8
             [b]: This set of adoption rates did not apply weight reduction to meet the proposed standards for these trailers

We request comment and any data related to our projections of technology adoption rates. The following section (d) explains how the agencies combined these adoption rates with the performance values shown previously to calculate the proposed standards.
Derivation of the Proposed Standards
  The average performance parameters from Table IV-14, and Table IV-15 were applied as input values to the GEM vehicle simulation to derive the proposed HD Phase 2 fuel consumption and CO2 emissions standards for each subcategory of trailers. The proposed standards are shown in Table IV-16.   The proposed standards for partial-aero trailers, which are not explicitly shown in Table IV-16, would be the same as their full-aero counterparts through MY 2026.  In MY 2027 and later, partial aero trailers would continue to meet the MY 2024 standards.
Over the four stages of the proposed rule, box trailers longer than 50 feet would, on average, reduce their CO2 emissions and fuel consumption by two percent, four percent, seven percent and eight percent compared to their reference cases.  Box trailers 50-foot and shorter would achieve reductions of two percent, three percent and four percent compared to their reference cases.  The tire technologies used on non-box and non-aero box trailers would provide reductions of two percent in the first two stages and achieve three percent by 2027.
Table IV-16:  Proposed Standards for Box Trailers
MODEL
YEAR
SUBCATEGORY
                                    DRY VAN
                               REFRIGERATED VAN
LENGTH
                                     LONG
                                     SHORT
                                     LONG
                                     SHORT
2018 - 2020
EPA Standard
                                      83
                                      144
                                      84
                                      147

(CO2 Grams per Ton-Mile)

Voluntary NHTSA Standard
                                    8.1532
                                    14.1454
                                    8.2515
                                    14.4401

(Gallons per 1,000 Ton-Mile)

2021 - 2023
EPA Standard
                                      81
                                      143
                                      82
                                      146

(CO2 Grams per Ton-Mile)

NHTSA Standard
                                    7.9568
                                    14.0472
                                    8.0550
                                    14.3418

(Gallons per 1,000 Ton-Mile)

2024 - 2026
EPA Standard
                                      79
                                      141
                                      81
                                      144

(CO2 Grams per Ton-Mile)

NHTSA Standard
                                    7.7603
                                    13.8507
                                    7.9568
                                    14.1454

(Gallons per 1,000 Ton-Mile)

2027 +
EPA Standard
                                      77
                                      140
                                      80
                                      144

(CO2 Grams per Ton-Mile)

NHTSA Standard
                                    7.5639
                                    13.7535
                                    7.8585
                                    14.1454

(Gallons per 1,000 Ton-Mile)

It should be noted that the proposed standards are based on highway cruise cycles that include road grade to better reflect real world driving and to help recognize engine and driveline technologies.  See Section III.E.  The agencies have evaluated some alternate road grade profiles recommended by the National Renewable Energy Laboratory (NREL) and have prepared possible alternative trailer vehicle standards based on these profiles.  The agencies request comment on this analysis, which is available in a memorandum to the docket.
Technology Costs for the Proposed Standards
The agencies evaluated the technology costs for 53-foot dry and refrigerated vans and 28-foot dry vans, which we believe are representative of the majority of trailers in the 50-foot and longer and shorter than 50-foot categories, respectively.  We identified costs for each technology package evaluated and projected the costs for each year of the program.  A summary of the technology costs is included in Table IV-17 through Table IV-20 for MYs 2018 through 2027, with additional details available in the draft RIA Chapter 2.12. Costs shown in the following tables are for the specific model year indicated and are incremental to the average reference case costs, which includes some level of adoption of these technologies as shown in Table IV-13.  Therefore, the technology costs in the following tables reflect the average cost expected for each of the indicated trailer classes.  Note that these costs do not represent actual costs for the individual components because some fraction of the component costs has been subtracted to reflect some use of these components in the reference case.  For more on the estimated technology costs exclusive of adoption rates, refer to Chapter 2.12 of the draft RIA.  These costs include indirect costs via markups and reflect lower costs over time due to learning impacts.  For a description of the markups and learning impacts considered in this analysis and how technology costs for other years are thereby affected, refer to Chapter 7 of the draft RIA.
Table IV-17:  Trailer Technology Incremental Costs in the 2018 Model Year (2012$)

                                    53-foot
                                    Dry Van
                                    53-foot
                               Refrigerated Van
                                    28-foot
                                    Dry Van
                                   Non-Aero
                                & Non-Box
Aerodynamics
                                                                           $285
                                                                           $285
                                                                             $0
                                                                             $0
Tires
                                                                            $65
                                                                            $65
                                                                            $78
                                                                           $185
Tire inflation system
                                                                           $239
                                                                           $239
                                                                           $435
                                                                           $683
Total
                                                                           $588
                                                                           $588
                                                                           $514
                                                                           $868

Table IV-18:  Trailer Technology Incremental Costs in the 2021 Model Year (2012$)

                                    53-foot
                                    Dry Van
                                    53-foot
                               Refrigerated Van
                                    28-foot
                                    Dry Van
                                   Non-Aero
                                & Non-Box
Aerodynamics
                                                                           $602
                                                                           $602
                                                                           $468
                                                                             $0
Tires
                                                                            $65
                                                                            $65
                                                                            $79
                                                                           $175
Tire inflation system
                                                                           $234
                                                                           $234
                                                                           $426
                                                                           $632
Total
                                                                           $901
                                                                           $901
                                                                           $974
                                                                           $807

Table IV-19: Trailer Technology Incremental Costs in the 2024 Model Year (2012$)

                                    53-foot
                                    Dry Van
                                    53-foot
                               Refrigerated Van
                                    28-foot
                                    Dry Van
                                   Non-Aero
                                & Non-Box
Aerodynamics
                                                                           $836
                                                                           $836
                                                                           $608
                                                                             $0
Tires
                                                                            $61
                                                                            $61
                                                                            $76
                                                                           $160
Tire inflation system
                                                                           $220
                                                                           $220
                                                                           $412
                                                                           $578
Total
                                                                         $1,116
                                                                         $1,116
                                                                         $1,097
                                                                           $739

Table IV-20:  Trailer Technology Incremental Costs in the 2027 Model Year (2012$)

                                    53-foot
                                    Dry Van
                                    53-foot
                               Refrigerated Van
                                    28-foot
                                    Dry Van
                                   Non-Aero
                                & Non-Box
Aerodynamics
                                                                         $1,163
                                                                         $1,034
                                                                           $788
                                                                             $0
Tires
                                                                            $54
                                                                            $54
                                                                            $74
                                                                           $155
Tire inflation system
                                                                           $192
                                                                           $192
                                                                           $391
                                                                           $549
Total
                                                                         $1,409
                                                                         $1,280
                                                                         $1,253
                                                                           $704

Reasonableness of the Proposed Standards
The agencies' proposed decisions on the stringency and timing of the proposed standards focused not only on available technology and the consequent emission reductions and fuel efficiency improvements associated with use of the technology, but also carefully considered issues of cost and lead time, taking into account the circumstances of the trailer manufacturing sector.  Trailer manufacturers would be subject to first-time emission control and fuel consumption regulation under the proposed standards.  These manufacturers are in many cases small businesses, with limited resources to master the mechanics of regulatory compliance.  Thus, the agencies' proposal seeks to provide a reasonable time for trailer manufacturers to become familiar with the requirements and the proposed new compliance regime, given the unique circumstances of the industry and the compliance flexibilities and optional compliance mechanisms specially adapted for this industry segment that we are proposing.
The stringency of the standard is predicated on more widespread deployment of aerodynamic and tire technologies that are already in commercial use.  The availability, feasibility, and level of effectiveness of these technologies are well-documented.  Thus the agencies do not believe that there is any issue of technical feasibility of the proposed standards.  Rather, the key issues reflected in the agencies' proposal are considerations of cost and sufficiency of lead-time  -  including lead-time not only to deploy technological improvements, but also this industry sector to assimilate for the first time the compliance mechanisms of the proposed rule.
The highest cost shown in Table IV-20 is associated with the long dry vans. We project that the average cost per trailer to meet the proposed MY 2027 standards for these trailers would be about $1,400, which is less than 10 percent of the cost of a new dry van trailer (estimated to be about $20,000).  Other trailer types have lower projected technology costs, and many have higher purchase prices.  As a result, we project that the per-trailer costs for all trailers covered in this regulation will be less than 10 percent of the cost of a new trailer.  This trend is consistent with the expected average control costs for Phase 2 tractors, which are also less than 10 percent of typical tractor costs (see Section III).
The agencies believe these technologies can be adopted at the rates the standards are predicated on within the proposed lead-time, as discussed above in Section IV.C.(3).  Moreover, we project that most owners would rapidly recover the initial cost of these technologies due to the associated fuel savings, usually in less than two years, as shown in the payback analysis in Section IX.  This payback period is generally considered reasonable in the trailer industry for investments that reduce fuel consumption.
Overall, as discussed above in IV.D.3.c in the context of our assumed technology adoption rates, the gradual increase in stringency of the proposed trailer program over the phase-in period recognizes two important factors that the agencies carefully considered in developing this proposed rule.  One factor is that assumed adoption of technologies many of the aerodynamic technologies that box trailer manufacturers would likely choose are available today and clearly technologically feasible throughout the phase-period.  At the same time, we recognize that the adoption of these technologies across the industry scale envisioned by the proposed program would likely take time.  The standards we are proposing in the interim years represent steady and yet reasonable improvement in average aerodynamic performance toward the final MY 2027 standards.
Alternative Standards and Feasibility Considered
As discussed in Section X, the agencies evaluated several different regulatory alternatives representing different levels of stringency for the Phase 2 program.  The results of the analysis of these proposed alternatives are discussed below in Section X of the preamble.  The agencies believe each alternative is feasible from a technical standpoint.  However, each successive alternative increases costs and complexity of compliance for the manufacturers, which can be a prohibitive burden on the large number of small businesses in the industry.  Table IV-21 provides a summary of the alternatives considered in this proposal.
Table IV-21:  Summary of Alternatives Considered for the Proposed Rulemaking
Alternative 1
No action alternative
Alternative 2
Expand the use of aerodynamic and tire technologies at SmartWay levels to all 53-foot box trailers
Alternative 3
(Proposed Alternative)
Adoption of advanced aerodynamic and tire technologies on all box trailers
Adoption of tire technologies on non-box trailers
Alternative 4
Same technology and application assumptions as Alternative 3 with an accelerated introduction schedule
Alternative 5
Aggressive adoption of advance aerodynamic and tire technologies for all box trailers
Adoption of aerodynamic and tire technologies for some tank, flatbed, and container chassis trailers
Adoption of tire technologies for the remaining non-box trailers
While we welcome comment on any of these alternatives, we are specifically requesting comment on Alternative 4 for the trailer program identified as Alternative 4 above and in Section X.  The same general technology effectiveness values were considered and much of the feasibility analysis was the same in this alternative and in the proposed alternative, but Alternative 4 applies the adoption rates of higher-performing aerodynamic technologies from Alternative 3 at earlier stages for box trailers.  This accelerated alternative achieves the same final fuel consumption and CO2 reductions as our proposed alternative three years in advance.  The following sections detail the adoption rates, reductions and costs projected for this alternative.
Effectiveness, Adoption Rates, and Technology Costs for Alternative 4
Alternative 4 includes the same trailer subcategories and same trailer technologies as the proposed alternative.  Therefore, the zero-technology baseline trailers (Table IV-7), reference case trailers (Table IV-10) and performance levels (Table IV-8) described in Section IV. D. apply for this analysis as well.  The following sections describe the adoption rates of this accelerated alternative and the associated benefits and costs.
Projected Technology Adoption Rates for Alternative 4
The adoption rates and average performance parameters projected by the agencies for Alternative 4 are shown in Table IV-22 and Table IV-23.  Adoption rates for non-aero box and non-box trailers remain unchanged from the proposed standards and they are not repeated in this section.  From the tables, it can be seen that the 2018 MY aerodynamic technology adoption rates and the tire technology adoption rates for all model years are identical to those presented previously for the proposed standards.  The aerodynamic projections for MY 2021 and MY 2024 in this accelerated alternative are the same as those projected for MY 2024 and MY 2027 of the proposed standards, but are applied three years earlier.  In this alternative, the 2021 MY adoption rates would continue to apply for the partial-aero box trailers in 2024 and later model years.
Table IV-22:  Adoption Rates and Average Performance Parameters for the Long Box Trailers in
 Alternative 4
TECHNOLOGY
                                   LONG BOX
                                   DRY VANS
                                   LONG BOX
                               REFRIGERATED VANS
Model Year
                                     2018
                                     2021
                                     2024
                                     2018
                                     2021
                                     2024
Aerodynamic Technologies [a]
Bin I
                                                                             5%

                                                                             5%

Bin II

Bin III
                                                                            30%

                                                                            30%

Bin IV
                                                                            60%
                                                                            25%

                                                                            60%
                                                                            25%

Bin V
                                                                             5%
                                                                            10%
                                                                            10%
                                                                             5%
                                                                            10%
                                                                            20%
Bin VI

                                                                            65%
                                                                            50%

                                                                            65%
                                                                            60%
Bin VII

                                                                            40%

                                                                            20%
Bin VIII

Average Delta CDA (m[2]) [a]
                                                                            0.4
                                                                            0.8
                                                                            1.1
                                                                            0.4
                                                                            0.8
                                                                            1.0
Trailer Tire Rolling Resistance
Baseline tires
                                                                            15%
                                                                             5%
                                                                             5%
                                                                            15%
                                                                             5%
                                                                             5%
Level 1 tires
                                                                            85%
                                                                            95%

                                                                            85%
                                                                            95%

Level 2 tires
                                                                            95%
                                                                            95%
Average CRR (kg/ton) [a]
                                                                            5.2
                                                                            5.1
                                                                            4.8
                                                                            5.2
                                                                            5.1
                                                                            4.8
Tire Inflation System
ATI
                                                                            85%
                                                                            95%
                                                                            95%
                                                                            85%
                                                                            95%
                                                                            95%
Average ATI Reduction (%) [a]
                                                                           1.3%
                                                                           1.4%
                                                                           1.4%
                                                                           1.3%
                                                                           1.4%
                                                                           1.4%
Weight Reduction (pounds)
Weight [b]

      Notes:
      A blank cell indicates a zero value
      [a]: Combines adoption rates with performance levels shown in Table IV-8
      [b]: This set of adoption rates did not apply weight reduction to meet the proposed standards for these trailers

Table IV-23: Adoption Rates and Average Performance Parameters for the Short Box Trailers in
 Alternative 4
TECHNOLOGY
                                   SHORT BOX
                                   DRY VANS
                                   SHORT BOX
                               REFRIGERATED VANS
Model Year
                                     2018
                                     2021
                                     2024
                                     2018
                                     2021
                                     2024
Aerodynamic Technologies [a]
Bin I
                                                                           100%

                                                                           100%

Bin II

                                                                            70%
                                                                            30%

                                                                            70%
                                                                            55%
Bin III

                                                                            30%
                                                                            60%

                                                                            30%
                                                                            40%
Bin IV

                                                                            10%

                                                                             5%
Bin V

Bin VI

Bin VII

Bin VIII

Average Delta CDA (m[2]) [b]
                                                                            0.4
                                                                            0.8
                                                                            1.1
                                                                            0.4
                                                                            0.8
                                                                            1.0
Trailer Tire Rolling Resistance
Baseline tires
                                                                            15%
                                                                             5%
                                                                             5%
                                                                            15%
                                                                             5%
                                                                             5%
Level 1 tires
                                                                            85%
                                                                            95%

                                                                            85%
                                                                            95%

Level 2 tires
                                                                            95%
                                                                            95%
Average CRR (kg/ton) [b]
                                                                            5.2
                                                                            5.1
                                                                            4.8
                                                                            5.2
                                                                            5.1
                                                                            4.8
Tire Inflation System
ATI
                                                                            85%
                                                                            95%
                                                                            95%
                                                                            85%
                                                                            95%
                                                                            95%
Average ATI Reduction (%) [b]
                                                                           1.3%
                                                                           1.4%
                                                                           1.4%
                                                                           1.3%
                                                                           1.4%
                                                                           1.4%
Weight Reduction (pounds)
Weight [c]

     Notes:
     A blank cell indicates a zero value
     [a]: The majority of short box trailers are 28 feet in length.  We recognize that they are often operated in tandem, which limits the technologies that can be applied (for example, boat tails). We established standards assuming these shorter trailers were run solo, but projected reduced aerodynamic improvements compared to the longer trailers with similar technologies to reflect their frequent tandem operation.
     [b]: Combines adoption rates with performance levels shown in Table IV-8
     [c]: This set of adoption rates did not apply weight reduction to meet the proposed standards for these trailers
Derivation of the Standards for Alternative 4
Similar to the proposed standards of Section IV. D. (3) (d), the agencies applied the technology performance values from Table IV-22 and Table IV-23 as GEM inputs to derive the proposed standards for each subcategory.
Table IV-24 shows the resulting standards for Alternative 4.  Over the three phases of the alternative, box trailers longer than 50 feet would, on average, reduce their CO2 emissions and fuel consumption by two percent, six percent and eight percent.  Box trailers 50-foot and shorter would achieve reductions of two percent, three percent, and four percent compared to the reference case.  Partial-aero box trailers would continue to be subject to the 2021 MY standards for MY 2024 and later.  The non-aero box and non-box trailers would meet the same standards as shown in the proposed Alternative 3 and achieve the same two and three percent benefits as shown in the proposed alternative.
Table IV-24:  Trailer CO2 and Fuel Consumption Standards for Box Trailers in Alternative 4
MODEL
YEAR
SUBCATEGORY
                                    DRY VAN
                               REFRIGERATED VAN
LENGTH
                                     LONG
                                     SHORT
                                     LONG
                                     SHORT
2018 - 2020
EPA Standard
                                      83
                                      144
                                      84
                                      147

(CO2 Grams per Ton-Mile)

Voluntary NHTSA Standard
                                    8.1532
                                    14.1454
                                    8.2515
                                    14.4401

(Gallons per 1,000 Ton-Mile)

2021 - 2023
EPA Standard
                                      80
                                      142
                                      81
                                      145

(CO2 Grams per Ton-Mile)

NHTSA Standard
                                    7.8585
                                    13.9489
                                    7.9568
                                    14.2436

(Gallons per 1,000 Ton-Mile)

2024+
EPA Standard
                                      77
                                      140
                                      80
                                      144

(CO2 Grams per Ton-Mile)

NHTSA Standard
                                    7.5639
                                    13.7525
                                    7.8585
                                    14.1454

(Gallons per 1,000 Ton-Mile)

Costs Associated with Alternative 4
A summary of the technology costs is included in Table IV-25 to Table IV-27for MYs 2018, 2021 and 2024, with additional details available in the draft RIA Chapter 2.12. Costs shown in the following tables are for the specific model year indicated and are incremental to the average reference case costs, which includes some level of adoption of these technologies as shown in Table IV-10.  Therefore, the technology costs in the following tables reflect the average cost expected for each of the indicated trailer classes.  Note that these costs do not represent actual costs for the individual components because some fraction of the component costs has been subtracted to reflect some use of these components in the reference case.  For more on the estimated technology costs exclusive of adoption rates, refer to Chapter 2.12 of the draft RIA.  These costs include indirect costs via markups and reflect lower costs over time due to learning impacts.  For a description of the markups and learning impacts considered in this analysis and how it impacts technology costs for other years, refer to the draft RIA.
Table IV-25:  Trailer Technology Incremental Costs in the 2018 Model Year for Alternative 4 (2012$)

                                    53-foot
                                    Dry Van
                                    53-foot
                               Refrigerated Van
                                    28-foot
                                    Dry Van
                                   Non-Aero
                                & Non-Box
Aerodynamics
                                                                           $285
                                                                           $285
                                                                             $0
                                                                             $0
Tires
                                                                            $65
                                                                            $65
                                                                            $78
                                                                           $185
Tire inflation system
                                                                           $239
                                                                           $239
                                                                           $435
                                                                           $683
Total
                                                                           $588
                                                                           $588
                                                                           $514
                                                                           $868

Table IV-26:  Trailer Technology Incremental Costs in the 2021 Model Year for Alternative 4 (2012$)

                                    53-foot
                                    Dry Van
                                    53-foot
                               Refrigerated Van
                                    28-foot
                                    Dry Van
                                   Non-Aero
                                & Non-Box
Aerodynamics
                                                                           $908
                                                                           $908
                                                                           $641
                                                                             $0
Tires
                                                                            $65
                                                                            $65
                                                                            $79
                                                                           $175
Tire inflation system
                                                                           $234
                                                                           $234
                                                                           $426
                                                                           $632
Total
                                                                         $1,207
                                                                         $1,207
                                                                         $1,146
                                                                           $807

Table IV-27: Trailer Technology Incremental Costs in the 2024 Model Year for Alternative 4 (2012$)

                                    53-foot
                                    Dry Van
                                    53-foot
                               Refrigerated Van
                                    28-foot
                                    Dry Van
                                   Non-Aero
                                & Non-Box
Aerodynamics
                                                                         $1,223
                                                                         $1,090
                                                                           $816
                                                                             $0
Tires
                                                                            $61
                                                                            $61
                                                                            $76
                                                                           $160
Tire inflation system
                                                                           $220
                                                                           $220
                                                                           $412
                                                                           $578
Total
                                                                         $1,504
                                                                         $1,371
                                                                         $1,304
                                                                           $739

The agencies believe that although the Alternative 4 costs and emission/fuel consumption reductions would be similar to those of Alternative 3, we have concerns about the adequacy of the significantly shorter lead-time for compliance with Alternative 4.  As discussed earlier, the ability for manufacturers in this industry to broadly take the necessary technical steps while becoming familiar with first-time regulatory responsibilities would be significantly limited with three fewer years of lead-time.  As reinforced in the SBAR Panel Report, this challenge would not be equal across the industry, often falling more heavily on smaller trailer manufacturers.
The agencies request comment on the feasibility and costs for trailer manufacturers to achieve the Alternative 4 standards by applying advanced aerodynamic technologies with three years less lead-time than Alternative 3 would provide.  The agencies also request comment on particular burdens that these aggressive adoption rates could have on small business trailer manufacturers.

Trailer Standards: Compliance and Flexibilities
Under the proposed structure, trailer manufacturers would be required to obtain a certificate of conformity from EPA before introducing into commerce new trailers subject to the proposed new trailer CO2 and fuel consumption standards.  See CAA section 206(a).  The certification process the agencies are proposing for trailer manufacturers is very similar in its basic structure to the process for the tractor program.  This structure involves pre-certification activities, the certification application and its approval, and end-of-year reporting.
In this section, the agencies first describe the GEM vehicle simulation tool and the general certification process, followed by a discussion of the proposed test procedures for measuring the performance of tires and aerodynamic technologies and how manufacturers would apply test results toward compliance and certification.  The section closes with discussions of several other proposed certification and compliance provisions as well as proposed provisions to provide manufacturers with compliance flexibility.
Role of the Greenhouse Gas Emission Model (GEM) Simulation Tool in Trailer Compliance
The agencies are committed to introducing a compliance program for trailer manufacturers that is straightforward, technically robust, transparent, and that minimizes new administrative burdens on the industry.  GEM is a customized vehicle simulation model that EPA developed for the Phase 1 program for demonstrating heavy-duty vehicle compliance. This approach allows characteristics of the vehicle to be measured directly and used as inputs to the simulation tool instead of performing full-vehicle testing.  For this proposed rulemaking, we are proposing that compliance with the trailer standards be demonstrated using the GEM simulation tool as a means of reducing the testing burden on trailer manufacturers.
For the proposed trailer program, the characteristics that a manufacturer would supply to the model are aerodynamic improvements (i.e., a change in the aerodynamic drag area, delta CDA), tire rolling resistance (i.e., coefficient of rolling resistance, CRR), the presence of an automatic tire inflation (ATI) system, and the use of pre-determined light-weight components.  The model quantifies the overall performance of the trailer in terms of CO2 emissions and fuel consumption on a per ton-mile basis.
General Certification Process
Under the proposed process for certification, trailer manufacturers would be required to apply to EPA for certification and would provide performance test data (see 40 CFR 1037.205) in their applications.  A staff member from EPA's Compliance Division (in the Office of Transportation and Air Quality) would be assigned to each trailer manufacturer to help them through the compliance process.  Although not required, we recommend that manufacturers arrange to meet with the agencies to discuss compliance plans and obtain any preliminary approvals (e.g., appropriate test methods) before applying for certification.
Trailer manufacturers would submit their applications through the EPA VERIFY electronic database, and EPA would issue certificates based on the information provided.  At the end of the model year, trailer manufacturers would submit an end-of-year report to the agencies to complete their annual obligations.
The proposed EPA certification provisions also contain provisions for applying to the NHTSA program.  EPA and NHTSA would coordinate on any enforcement action required.
Preliminary Considerations for Compliance
Prior to submitting an application for a certificate, a manufacturer would choose the technologies they plan to offer their customers, obtain performance information for these technologies, and identify any trailers in their production line that qualify for exclusion from the program.  Manufacturers that choose to perform aerodynamic or tire testing would obtain approval of test methods and perform preliminary testing as needed.  During this time, the manufacturer would also decide the strategy they intend to use for compliance by identifying "families" for the trailers they produce.  A family is a grouping of similar products that would all be subject to the same standard and covered by a single certificate.
At its simplest, the program would allow all products in each of the trailer subcategories to be certified as separate families.  That is, long box dry vans, short box dry vans, long refrigerated vans, short refrigerated vans, non-box trailers, partial-aero trailers (long and short box, dry and refrigerated van), and non-aero trailers, could each be certified as separate trailer families.  If a manufacturer chooses this approach, all products within a family would need to meet or do better than the standards for that trailer subcategory.  This is not to say that, for example, every long box dry van model would need to have identical technologies like skirts, tires, and tire inflation systems, but that every model in that family would need to have a combination of technologies that had performance representative of testing demonstrated for that family.  (Because the manufacturer would not be using averaging provisions, a trailer that "over-complied" could not offset a trailer that did not meet that family's emission limit).
If a trailer manufacturer wishes to take advantage of the proposed averaging provisions, it could divide the trailer models in each of the standard box trailer categories (i.e., not including the non-box trailer or non-aero box trailer categories) into subfamilies.  Each subfamily could be a grouping of trailers that have with similar performance levels, even if they use different technologies.  We call the performance levels for each subfamily as "Family Emission Limits" (FELs).  A long box dry van manufacturer could choose, for example, to create two or more subfamilies in its long box dry van family.  Trailers in one or more of these subfamilies could be allowed to under-comply with the standard (e.g., if the manufacturer chose not to apply ATI or chose tires with higher rolling resistance levels) as long as the performance of the other subfamilies over-comply with the standard (e.g., if the manufacturer applied higher-performing skirts) such that the average of all of the subfamilies' FELs met or did better than the stringency for that family on a production-weighted basis.  Section IV.F.6.a below further discusses how the proposed averaging program would function for any such trailer subfamilies.
Submitting a Certification Application and Request for a Certificate to EPA
Once the preliminary steps are completed, the manufacturer can prepare and submit applications to EPA for certificate of conformity for each of its trailer families.  The contents of the application are specified in 40 CFR 1037.205, though not all items listed in the regulation are applicable to each trailer manufacturer.
For the early years of the program (i.e., 2018 through 2020), the application must specify whether the trailer manufacturer is opting into the NHTSA voluntary program to ensure the information is transferred between the agencies.  It must also include a description of the emission controls that a manufacturer intends to offer.  These emission controls could include aerodynamic features, tire models, tire inflation systems or components that qualify for weight reduction.  Basic information about labeling, warranty, and recommended maintenance should also be included the application (see Section IV.F.5 for more information).
The manufacturer would also provide a summary of the plans to comply with the standard.  This information would include a description of the trailer family and subfamilies (if applicable) covered by the certificate and projected sales of its products.  Manufacturers that do not participate in averaging would include information on the lowest level of CO2 and fuel consumption performance offered in the trailer family.  Manufacturers who choose to average within their families would include performance information for the projected highest production trailer configuration, as well as the lowest and the highest performing configurations within that trailer family.
End-of-Year Obligations
After the end of each year, all manufacturers would need to submit a report to the agencies presenting production-related data for that year (see 40 CFR 1037.250 and 49 CFR 535.8).  In addition, manufacturers participating in the averaging program would submit an end-of-year report containing both emissions and fuel consumption information for both agencies.  This report would include the year's final compliance data (such as GEM results) and actual sales in order to demonstrate that the trailers either met the standards for that year or that the manufacturer generated a deficit to be reconciled within the next three years under the averaging provisions (see 40 CFR 1037.250 and 49 CFR 535.7).  All certifying manufacturers would need to maintain records of all the data and information required to be supplied to EPA and NHTSA for eight years.
Trailer Certification Test Protocols
The Clean Air Act specifies that compliance with emission standards for motor vehicles be demonstrated using emission test data (see CAA section 206(a) and (b)).  The Act does not require the use of specific technologies or designs.  Similar to the tractor and vocational vehicle programs, the agencies are proposing that, for the long term, the GEM simulation tool function as the official "test procedure" for quantifying CO2 and fuel consumption performance for trailer compliance and certification.  The model requires performance information from the trailer technologies applied in order to calculate their impact on overall trailer performance.  The agencies are proposing to assign performance levels to ATI systems and specific weight reduction values to pre-determined component substitutions.  Aerodynamic and tire rolling resistance performance would be obtained by the trailer manufacturers.  The following sections describe the approved performance tests for tire rolling resistance and aerodynamic drag.  Non-box and non-aero box trailers have tire requirements only.  Manufacturers of these trailers will only need to obtain results from the tire performance tests.  Long and short box trailers are expected to use aerodynamic and tire technologies to meet the proposed standards and will need to obtain test results from both procedures.  See generally proposed 40 CFR part 1037, subpart F for full description of the proposed performance tests, and see in particular proposed sections 1037.520(a)(1)(i)-(iii), (b)(4), and (c).
Trailer Tire Performance Testing
Under Phase 1, tractor and vocational chassis manufacturers are required to input the tire rolling resistance coefficient into GEM and the agencies adopted the provisions in ISO 28580:2009(E) to determine the rolling resistance of tires.  As described in 40 CFR 1037.520(c), this measured value, expressed as CRR, is required to be the result of at least three repeat measurements of three different tires of a given design, giving a total of at least nine data points.  Manufacturers specify a CRR value that for GEM that may not be lower than the average of these nine results.  Tire rolling resistance may be determined by either the vehicle or tire manufacturer. In the latter case, the tire manufacturer would provide a signed statement confirming that it conducted testing in accordance with this part.
Similar to the tractor program, we propose to extend the Phase 1 testing provisions for tire rolling resistance to apply to the Phase 2 trailer program.  The average rolling resistance value obtained from this test would be used to specify the tire rolling resistance level (TRRL) for the trailer tires in the GEM simulation.  Based on the current practice for tractors, we expect the trailer manufacturers to obtain these data from tire manufacturers.  We welcome comments regarding the proposed tire testing provisions as they relate to the proposed trailer program.
Trailer Aerodynamic Performance Testing
Our proposed trailer aerodynamic test procedures are based on the current and proposed tractor procedures for testing aerodynamic control devices, including coastdown, constant speed, wind tunnel, and computational fluid dynamics (CFD) modeling.  The purpose of the tests is to establish an estimate of the aerodynamic drag experienced by a tractor-trailer vehicle in real-world operation. In the tractor program, the resulting CdA value represents the aerodynamic drag of a tested tractor assumed to be pulling a specified standard trailer.  In the proposed trailer program, the CDA value modeled in GEM would represent the tested trailer pulled by a standard tractor.
Details of the test procedures can be found in 40 CFR 1037.521 and a discussion of EPA's aerodynamic testing program as it relates to the proposed trailer program are provided in the draft RIA Chapter 3.2.  The following sections outline the testing requirements proposed for the long term trailer program, as well as simpler testing provisions that would apply in the nearer term.
A to B Testing for Trailer Aerodynamic Performance
A key difference between the proposed tractor and trailer programs is that while the tractor procedures provide a direct measurement of an absolute CDA value for each tractor model, the agencies expect a majority of the aerodynamic improvements for trailers will be accomplished by adding bolt-on technologies.  As a result, we are proposing to evaluate the aerodynamic improvements for trailers by measuring a change in CDA (delta CDA) relative to a baseline.   Specifically, we propose that the trailer tests be performed as "A to B" tests, comparing the aerodynamic performance of a tractor-trailer without a trailer aerodynamic device to one with the device installed.  See Draft RIA Chapter 2.10 for more information on this approach.
The agencies note that it was relatively straightforward in Phase 1 to establish a standard trailer with enough specificity to ensure consistent testing of tractors, since there are relatively small differences in aerodynamic performance of base-model dry van trailers.  However, as discussed in Chapter 2.10 of the draft RIA, small differences in tractor design can have a significant impact on overall tractor-trailer aerodynamic performance.  An advantage of an A to B test approach for trailers is that many of the differences in tractor design are canceled-out, which allows a variety of standard tractors to be used in testing without compromising the evaluation of the trailer aerodynamic technology.  Thus, the relative approach does not require the agencies to precisely specify a standard tractor, nor does it require trailer manufacturers to purchase, modify or retain a specific tractor model in order to evaluate their trailers.
 In essence, an A to B test is a set of tests: one test of a baseline tractor-trailer with zero trailer aerodynamic technologies (A), and one test that includes the aerodynamic devices to be tested (B).  However, because an A test would relate to a B test only with respect to the test method and the test trailer length, one A test could be used for many different B tests.  This type of testing would result in a delta CDA value instead of an absolute CDA value.  For the trailer program, the vehicle configuration in the A test would include a standard tractor that meets specified characteristics, and a manufacturer's baseline trailer with no aerodynamic improvements.  The entity conducting the testing (e.g., the trailer manufacturer or the trailer aerodynamic device manufacturer, as discussed below) would perform the test for this configuration according to the procedures in 40 CFR 1037.521 and repeat the test for the B configuration, which includes the trailer aerodynamic package/device(s) being tested.  The delta CDA value for that trailer with that device would be the difference between the CDA values obtained in the A and B tests.
In the event that a trailer manufacturer makes major changes to the aerodynamic design of its trailer in lieu of installing add-on devices, trailer manufacturers would use the same baseline trailer for the A configuration as would be used for bolt-on features.  In both cases, the baseline trailer would be a manufacturer's standard box trailer.   Thus, the manufacturer of a redesigned trailer would get full credit for any aerodynamic improvements it made.
The agencies are proposing to determine the delta CDA for trailer aerodynamics using the zero-yaw (or head-on wind) values.  The agencies are not proposing a reference method (i.e., the coastdown procedure in the tractor program).  Instead, we are proposing to allow manufacturers to perform any of the proposed test procedures to establish a delta CDA.  Since the proposed coastdown and constant speed procedures include wind restrictions, we are proposing to only accept the zero-yaw values from aerodynamic evaluation techniques that are capable of measuring drag at multiple yaw angles (e.g., wind tunnels and CFD) to allow cross-method comparison and certification.  The agencies welcome comment on the pros and cons of exclusive use of zero-yaw data from trailer aerodynamic compliance testing.  We recognize that the benefits of aerodynamic devices can be higher when measured considering wind from other yaw angles.  We request comment on the possibility of allowing manufacturers to use wind-averaged results for compliance if they choose to test using procedures that provide wind-averaged values.  Chapter 2.10 of the draft RIA compares zero-yaw and wind-averaged results from EPA's wind tunnel testing.  We request that commenters provide test data to support any preference for compliance test results. We also request comments on strategies that could be used to maintain consistency with other methods that cannot provide wind-averaged results.
Standard Tractor for Aerodynamic Testing in the Proposed Trailer Program
The final test procedure for trailer compliance will be to use EPA's GEM vehicle simulation tool.  Our discussion of the feasibility of our proposed standards (Section IV. D. (3) (a)) includes a description of the tractor-trailer vehicle used in that model.  We recognize the impact of the tractor and want to maintain consistency with GEM, but it is not necessary to address all aspects (e.g., the engine) of the tractor, because, as explained above, the impact of many of its features will be canceled-out with the use of an A to B test strategy.  However, some aerodynamic design features of the tractor can influence the performance of trailer aerodynamic technologies and we want to ensure a level of consistency between tests of different trailer manufacturers.
The agencies believe the A to B test strategy would reduce the degree of precision with which the standard tractor needs to be specified.  Instead of identifying a specific make and model of a tractor to be used over the entire duration of the program, the agencies would instead identify key characteristics of a standard tractor.  EPA's trailer testing program investigated the impact of tractor aerodynamics on the performance of trailer aerodynamic technologies, as mentioned in Chapter 2.10 of the draft RIA.  In order to maintain a minimal level of performance, we are proposing that tractors used in trailer aerodynamic tests meet Phase 2 Bin III or better tractor requirements (See Section III.D.).  We believe the majority of tractors in the U.S. trucking fleet will be Bin III or better in the timeframe of this rulemaking, and trailer manufacturers have the option to choose higher-performing tractors in later years as tractor technology improves.  The standard tractor for long-box trailers is a Class 8 high-roof sleeper cab.  The standard tractor for short box trailers is a Class 8 high roof day cab.  Trailer manufacturers are free to choose any standard tractor that meets these criteria in their aerodynamic performance testing.  See 40 CFR 1037.501.
Bins for Aerodynamic Performance
As mentioned in Section IV. D. (1) (a), the agencies are proposing aerodynamic bins for manufacturers to account for testing variability and to provide consistency in the model parameters provided to GEM.  These bins were developed in terms of delta CDA ranges, and designed to be broad enough to cover the range of uncertainty seen in our aerodynamic testing program in terms of test-to-test variability as well as variability due to differences in test method, tractor models, trailer models and device models.
Table IV-28:  Aerodynamic Bins Used to Determine GEM Inputs for Trailer Certification
                         DELTA CDA MEASURED IN TESTING
                                      BIN
                                   AVERAGE
                                  DELTA CDA
                                 INPUT FOR GEM
                                     0.09
                                     Bin I
                                      0.0
                                  0.10 - 0.19
                                    Bin II
                                      0.1
                                  0.20 - 0.39
                                    Bin III
                                      0.3
                                  0.40 - 0.59
                                    Bin IV
                                      0.5
                                  0.60 - 0.79
                                     Bin V
                                      0.7
                                  0.80 - 1.19
                                    Bin VI
                                      1.0
                                  1.20 - 1.59
                                    Bin VII
                                      1.4
                                   > 1.6
                                   Bin VIII
                                      1.8
A manufacturer that wished to perform testing would first identify a standard tractor (according to 40 CFR 1037.521) and a representative baseline trailer with no aerodynamic features, then perform the A to B tests with and without aerodynamic devices and obtain a delta CDA value.  The manufacturer would use Table IV-28 to determine the appropriate bin based on their delta CDA.  Each bin has a corresponding average delta CDA value which is the value manufacturers apply in GEM for compliance.
Aerodynamic Device Testing Alternative
The agencies recognize that much of the trailer manufacturing industry may have little experience with aerodynamic performance testing.  As such, we are proposing an alternative compliance option that we believe will minimize the testing burden for trailer manufacturers, meet the requirements of the Clean Air Act and of EISA, and provide reasonable assurance that the anticipated CO2 and fuel consumption benefits of the program will be realized in real-world operation.
The agencies are proposing to allow trailer aerodynamic device manufacturers to seek preliminary approval of their devices (or combinations of devices) based on the same performance tests described previously in Section IV. F. (3) (b)(i).  Device manufacturers would perform the required A to B testing of their device(s) on a trailer that meets the requirements specified in 40 CFR 1037.211 and 1037.521(b)(3) and submit the performance results, in terms of delta CDA, directly to EPA.  Trailer manufacturers could then choose to adopt approved devices and apply their performance levels in the certification application for their trailer families.  This approach would provide an opportunity for trailer manufacturers to choose EPA pre-approved technologies for installation on their new trailers and obtain the performance values needed for certification with GEM without performing their own aerodynamic testing.  We note that this proposed testing alternative is consistent with recommendations of the SBAR Panel.  The Panel Report is summarized below in Section XV.D.
If trailer manufacturers wish to use multiple devices that were individually pre-approved for Phase 2, the proposed program provides a process for combining the effects of multiple devices to determine an appropriate delta CDA value for compliance.   More specifically, such manufacturers would fully count the technology with largest delta CDA value, discount the second by 10 percent, and discount each of the remaining additional technologies by 20 percent.  This discounting would acknowledge the complex interactions among individual aerodynamic devices and would provide a conservative value for the impact of the combined devices.  For example, a manufacturer applying three separately tested devices with delta CDA values of 0.40, 0.30, and 0.10 would calculate the combined delta CDA as:
Delta CDA = 0.40 + 0.90*0.30 + 0.80*0.10 = 0.75 m[2]
In addition, the agencies believe that discounting the delta CDA values of individually-tested devices used as a combination would provide a modest incentive for trailer or device manufacturers to test and get EPA pre-approval of the combination as an aerodynamic system for compliance.  We propose that device manufacturers be allowed to test and receive EPA pre-approval for combinations of devices, and that trailer manufacturers that wish to use those specific combinations be allowed to use the results from the tests of the combined devices.
The agencies propose that this alternative testing approach  -  whereby device manufacturers rather than trailer manufacturers do aerodynamic testing  -  be an interim measure, although we are not proposing an end date at this time.  Rather we would monitor use of this option and make changes in the future as necessary.  The agencies note that many of the largest box trailer manufacturers are already performing aerodynamic test procedures to some extent, and the agencies expect other box trailer manufacturers will increasingly be capable of performing these tests as the program progresses.
The proposed alternative testing approach is intended to allow trailer manufacturers to focus on and become familiar with the certification process in the early years of the program and, if they wish, begin to perform testing in the later years, when it may be more appropriate for their individual companies.  This approach would not preclude trailer manufacturers from performing their own testing at any time, even if the technologies they wish to install are already pre-approved.  For example, a manufacturer that believed a specific trailer actually performed in a more synergistic manner with a given device than the device's pre-approved delta CDA value suggested could perform its own testing and submit the results to EPA for certification.  The process to obtain approval is outlined in the proposed 40 CFR 1037.150(n) and 1037.211.
Use of GEM for Trailer Compliance
The agencies are proposing standards for non-box and non-aero box trailers based on the use of tires with rolling resistance levels at or below a threshold, and on ATI systems.  As part of their certification application, manufacturers of these trailers would submit their tire rolling resistance levels and a description of their ATI system(s) to EPA.  As long as the trailer manufacturer certifies that they will install the appropriate tires and ATI systems on all of their trailers, the agencies do not believe it is necessary to require these trailer manufacturers to use GEM and report the results of the model to the agencies to demonstrate compliance.  We are not proposing to recognize weight reduction options for these trailers in this proposal as a means of reducing the compliance burden on these manufacturers.  We seek comment on this decision and welcome suggestions that would allow non-box and non-aero box trailers to adopt weight reduction strategies without the potential added burden of using averaging or using GEM to adequately demonstrate performance.
Box trailer manufacturers who apply more than tire technologies to meet the standards would use GEM to combine the effects of these technologies and quantify the overall performance of the vehicle to demonstrate compliance.  Trailer manufacturers would obtain delta CDA and tire rolling resistance values from testing (either from their own testing or testing performed by another entity as described previously) and note if they installed a qualifying automatic tire inflation system or made a component substitution that qualifies for weight reduction.  Manufacturers would directly apply the delta CDA and TRRL values into the model.  By selecting "yes" to an ATI system, GEM would apply a 1.5 percent reduction in CO2 and fuel consumption.  Qualifying components for weight reduction can be found in 40 CFR 1037.520(e).  Manufacturers that substitute one or more of these components on their box trailers would sum the weight reductions assigned to each component and enter that total into the GEM input file.  GEM will assign one-third of that reduced weight to increase the payload and the remaining reduces the overall weight of the simulated vehicle.
For this proposal, we are requiring that GEM be used to take advantage of the agencies' proposed averaging provisions.  Prior to submitting a certificate application, manufacturers would decide which technologies to make available for their customers and use GEM to determine the range performance of the packages they will offer.  Manufacturers would supply these GEM results in their certificate application and those manufacturers that wish to perform averaging would continue to run GEM throughout the model year and keep records of the results for each trailer package sold.  As described in Section IV.F.2.c above, at the end of the year, manufacturers would submit two reports.  One report would include their production volumes for each configuration.  The second report, required for manufacturers using averaging, would summarize the families and subfamilies, and CO2 emissions and fuel consumption results from GEM for all of the trailer configurations they build.
Box trailer manufacturers who do not participate in averaging would also use GEM to ensure that all of the trailer configurations they offer will meet the standard for the given model year.  These GEM runs could be performed by the manufacturer prior to submitting a certificate application, but it is not necessary for the manufacturer to use GEM throughout the model year unless a new technology package is offered.  These manufacturers would submit a single end-of-year report that would include their production volumes and confirmation that all of their trailers applied the technology packages outlined in their application.
Proposed Design-Based Certification Option
We are proposing interim provisions for MY 2018 through MY 2023 that would allow trailer manufacturers to forgo the use of GEM by using an optional "design-based" certification approach.  (This approach would be an optional means of complying with the standards; it is not related to the proposed "design-based standards" discussed in IV.D.3.d above)  That is, manufacturers that choose this option would need to meet certain technical characteristics.  Specifically, for those trailers, manufacturers would need to apply ATI systems and meet minimum performance thresholds for tire rolling resistance and delta CDA, where applicable (Table IV-29).  Averaging provisions would not apply under this option.  Although the SBAR Panel did not specifically consider this approach, we believe that small manufacturers of trailers would likely find this simplifying technique to be especially useful.
Several aerodynamic technology options and tire models are available that meet the minimum requirements in the table, and trailer manufacturers would continue to have a choice in ATI systems.  The agencies believe that although these provisions would somewhat reduce a trailer manufacturer's flexibility compared to the primary program, the provisions would still provide trailer manufacturers multiple means of achieving the requirements.  The added benefit of these provisions would be a significantly lower compliance burden in the early years of the program.
The agencies request comment on this proposed design-based certification option.  We are particularly interested in comments related to extending this option beyond 2023, including whether a design-based certification strategy would be feasible in the later years of the program when manufacturers would be required to apply technologies in the highest bins for 100 percent of the trailers in each family.
Table IV-29:  Minimum Requirements for Trailer Manufacturers Opting into the Proposed Design-Based Certification Provisions
TECHNOLOGY
                                   LONG BOX
                                   TRAILERS
                                   SHORT BOX
                                   TRAILERS
Model Year
                                   2018-2020
                                   2021-2023
                                   2018-2020
                                   2021-2023
Aerodynamic Technologies
Bin I

                                                                           100%

Bin II

                                                                           100%
Bin III

Bin IV
                                                                           100%

Bin V

                                                                           100%

Bin VI

Bin VII

Bin VIII

Average Delta CDA (m[2])
                                                                            0.5
                                                                            0.7
                                                                            0.0
                                                                            0.1
Trailer Tire Rolling Resistance
Baseline tires

Level 1 tires
                                                                           100%
                                                                           100%
                                                                           100%
                                                                           100%
Level 2 tires
                                                           AVERAGE CRR (KG/TON)
                                                                            5.1
                                                                            5.1
                                                                            5.1
                                                                            5.1
Tire Inflation System
ATI
                                                                           100%
                                                                           100%
                                                                           100%
                                                                           100%
Average ATI Reduction (%)
                                                                           1.5%
                                                                           1.5%
                                                                           1.5%
                                                                           1.5%
Weight Reduction (pounds)
Weight
                                                                             NA
                                                                             NA
                                                                             NA
                                                                             NA
     Note:  A blank cell indicates a zero value

Additional Certification and Compliance Provisions
Trailer Useful Life
Section 202(a)(1) of the CAA specifies that EPA is to propose emission standards that are applicable for the "useful life" of the vehicle.  Based on our own research and discussions with trailer manufacturers, EPA and NHTSA are proposing a regulatory useful life value for trailers of 10 years.  This useful life represents the average duration of the initial use of trailers, before they are moved into less rigorous (e.g., limited use or storage) duty.  We note that the useful life value is 10 years for other heavy-duty vehicles.  However, unlike the other vehicles, we are not proposing to set a mile value for trailers because we do not require odometers for trailers.
Thus, we propose that trailer manufacturers be responsible for meeting the CO2 emissions and fuel consumption standards for 10 years after the trailer is produced.  We believe that manufacturers would be able to demonstrate at certification that their trailers will comply for the useful life of the trailers without durability testing.  The aerodynamic technologies that we expect manufacturers to use to comply with the proposed standards, including side skirts and boat tails, are designed to continue to provide their full potential benefit indefinitely as long as no serious damage occurs.  (See also Section IV.C.6 above describing why we are not proposing separate in-use standards).
Regarding trailer tires, we recognize that the original lower rolling resistance tires will wear over time and will be replaced several times during the useful life of a trailer, either with new or retreaded tires.  As with the Phase 1 tractor program, to help ensure that trailer owners have sufficient knowledge of which replacement tires to purchase in order to retain the as-certified emission and fuel consumption performance of their trailer for its useful life, we are proposing to require that trailer manufacturers supply adequate information in the owner's manual to allow the trailer owner to purchase replacement tires meeting or exceeding the rolling resistance performance of the original equipment tires.  We believe that the favorable fuel consumption benefit of continued use of LRR tires would generally result in proper replacements throughout the 10-year useful life.  Finally, we are requiring that ATI systems remain effective for at least the 10 year useful life, although some servicing may be necessary.  (See the maintenance discussion in Section IV.D.4.e).
Emission Control Labels
Historically, EPA-certified vehicles are required to have a permanent emission control label affixed to the vehicle.  The label facilitates the identification of the vehicle as a certified vehicle.  For the trailer program, EPA proposes that the labels include the same basic information as we are proposing to require for tractor labels.  For trailers, this information would include the manufacturer, a trailer identifier such as the Vehicle Identification Number, the trailer family and regulatory subcategory, the date of manufacture, and compliance statements.  Although the proposed Phase 2 label for tractors would not include emission control system identifiers (as previously required for tractors in the Phase 1 program in 40 CFR 1037.135(b) (6)), we are proposing that these identifiers be included in the trailer labels.  As for tractors, we would require manufacturers to maintain records that would allow us to verify that an individual trailer was in its certified configuration.
Warranty
Section 207 of the CAA requires manufacturers to warrant their products to be free from defects that would otherwise cause non-compliance with emission standards.  For purposes of the proposed trailer program, EPA would require trailer manufacturers to warrant all components that form the basis of the certification to the CO2 emission standards.  The emission-related warranty would cover all aerodynamic devices, lower rolling resistance tires, automatic tire inflation systems, and other components that may be included in the certification application.
The trailer manufacturer would need to warrant that these components and systems are designed to remain functional for the warranty period.  Based on the historical practice of requiring emissions warranties to apply for half of the useful life, we propose that the warranty period for trailers be 5 years for everything except tires.  For trailer tires, we propose to apply a warranty period of 1 year.  Manufacturers could offer a more generous warranty if they chose; however the emissions related warranty may not be shorter than any other warranty offered without charge for the vehicle.  If aftermarket components were installed (unrelated to emissions performance) that offer a longer warranty, this would not impact emission related warranty obligations of the vehicle manufacturer. NHTSA is not proposing any warranty requirements relating to its trailer fuel consumption program.
At the time of certification, manufacturers would need to supply a copy of the warranty statement that they would supply to the end customer.  This document would outline what is covered under the GHG emissions related warranty as well as the duration of coverage.  Customers would also have clear access to the terms of the warranty, the repair network, and the process for obtaining warranty service.
Maintenance
In general, EPA requires that vehicle manufacturers specify maintenance schedules to keep their product in compliance with emission standards throughout the useful life of the vehicle (CAA section 207).  For trailers, such maintenance could include fairing adjustments or service to ATI systems.  However, EPA believes that any such maintenance is likely to be performed by operators to maintain the fuel savings of the components, and we are not proposing  that trailer manufacturers be required submit a maintenance schedule for these components as part of its application for certification.
Since low rolling resistance tires are key emission control components under this program, and will likely require replacement at multiple points within the life of a vehicle, it is important to clarify how tires would fit into the emission-related maintenance requirements.  Although the agencies encourage the exclusive use of LRR tires throughout the life of trailers vehicles, we do not proposed to hold trailer manufacturers responsible for the actions of operators.  We do not see this as problematic because we believe that trailer operators have a genuine financial motivation for ensuring their vehicles are as fuel efficient as possible, which includes purchasing LRR replacement tires.  Therefore, as mentioned in Section IV.F.5.a above, to help ensure that trailer owners have sufficient knowledge of which replacement tires to purchase in order to retain the as-certified emission and fuel consumption performance of their trailer, we are proposing to require that trailer manufacturers supply adequate information in the owner's manual to allow the trailer owner to purchase tires meeting or exceeding the rolling resistance performance of the original equipment tires. We would require that these instructions would be submitted to EPA as part of the application for certification.
Flexibilities
The trailer program that the agencies are proposing incorporates a number of provisions that would have the effect of providing flexibility and easing the compliance burden on trailer manufacturers while maintaining the expected CO2 and fuel consumption benefits of the program.  Among these is the basic approach we used in setting the proposed standards, including the staged phase-in of the standards, which would gradually increase the CO2 and fuel consumption reductions that manufacturers would need to achieve over time as they also increase their experience with the program.  As described in the general certification discussion above (Section IV.F.2), another proposed provision would allow trailer manufacturers to designate broad trailer families that would aggregate several models with similar technologies or performance, thus potentially limiting the number of families and the associated family-level compliance requirements.
In addition to these provisions inherent to the proposed trailer program, the agencies are proposing additional options for certification that we believe would be very valuable to many trailer manufacturers.  One of these is the proposed process for component manufacturers to submit test data directly to EPA for review by the agencies in advance of formal certification, allowing a trailer manufacturer to reduce the amount of testing needed to demonstrate compliance or avoid it altogether.  (See Section IV.F.4 above).
Proposed Averaging Provisions
The agencies are also proposing a limited averaging program as a part of the trailer compliance process for box trailers.  This program would be similar to the Phase 1 averaging program for other sectors, but would be narrower in scope to reflect the unique competitive aspects of the trailer market.  The trailer manufacturing industry is very competitive, and manufacturers must be highly responsive to their customers' diverse demands.  Compared to other industry sectors, this reality can limit the value of the flexibility that averaging could provide to trailer manufacturers, since they can have little control over what kinds of trailer models their customers demand and thus limited ability to manage the mix and volume of different products.  In addition, the majority of trailer manufacturers have very few basic trailer models to offer, potentially putting them at a competitive disadvantage to the small number of larger companies that would be in a position to meet market demands that the smaller companies could not.  For example, one of the larger, more diverse manufacturers could potentially supply a customer with trailers that had few if any aerodynamic features, while offsetting this part of their business with over-complying trailers that they were able to sell to another customer; many smaller companies with limited product offerings might not be able to compete for those customers.
Although we recognize that there might be potential negative impacts on at least some trailer manufacturers of an average program, we believe that there may be overall value to such a program.  We propose that full-aero box trailer manufacturers may optionally comply with their standards on average for a trailer family in any given model year.  We are not proposing to allow partial-aero box trailers to average.  Instead, all trailers in partial-aero families would need to meet the standard for that subcategory.  We are proposing to allow a trailer manufacturer to combine partial-aero box trailers with the corresponding full-aero trailer family and reduce the number of certification applications required.  We expect this to be particularly beneficial to manufacturers in the early years of the program, when these two trailer categories have identical standards.  Although this option should reduce the compliance paperwork, the partial-aero trailers would not be able to adopt enough technologies to meet the full-aero standards in the later years, and manufacturers would have the option of creating a separate family for these trailers.  Additionally, we are proposing to allow refrigerated trailers to combine with the dry vans of the same length and meet the dry van standards and to allow short box vans to combine with their long box counterparts to meet the long box standards.
Unlike averaging programs in other sectors, including those in this Phase 2 program, we propose that averaging be limited to a single model year, and manufacturer not be allowed to "bank" credits generated from over-compliance in one year for use in a future year.  In other words, a manufacturer that produces some trailers in a family that perform better than required by the applicable standard would be allowed to produce a number of trailers that do not meet the standards, provided the average of the trailers it produces in any given model year is at or below the standards.  A trailer family performing better than the standard would not be allowed to bank credits for a future model year.  However, as a temporary recourse for unexpected challenges in a given model year, we propose that manufacturers be allowed to generate a deficit that would be resolved within the next three model years, and to allow the manufacturer to use credits they generate from over-compliance in subsequent years to address deficits from prior model years.  As discussed below, we are not proposing this allowance for non-box trailers or non-aero trailers.
We recognize that at each stage of the program, there may be a small fraction of trailer applications for which the trailer manufacturers cannot easily apply all of the aerodynamic and tire technologies.  Thus the proposed dry and refrigerated van standards are designed in the form of family average performance, meaning that each trailer manufacturer would comply on average across the trailer families it produces within each subcategory category (or family).  The proposed program would allow a manufacturer, for example, to comply without full adoption of aerodynamic devices across 100 percent of its box trailer production in a trailer family, as long as it also produced a sufficient number of trailers within that family that performed better than the standard, such that the overall production-weighted GEM results of the trailer models in that family complied with the appropriate standard.
In addition to the flexibility created by averaging, the proposed box trailer standards themselves are not predicated on a set adoption rate of any one technology.  Manufacturers would be free under the proposed averaging program to choose to apply the appropriate number and type of technologies that met their customers' needs and the level of performance required within a particular trailer family.  The proposed rules in general do not mandate inclusion of any particular technology or other means of emission control.  The agencies believe that, ordinarily, averaging would create an incentive for manufacturers to promote high-performing technologies for some customers, beyond the requirements for that given year, in order to provide other customers with trailers with fewer aerodynamic technologies.
The agencies also recognize, however, that an averaging program would inherently require a higher degree of data management, record keeping, and reporting than one without averaging.  Recognizing that this could impose burdens, especially on small business manufacturers, the agencies are proposing that the averaging provisions be optional; a box trailer manufacturer could choose whether to use averaging for any or all of its standard box trailer subcategories (families), or to forego averaging and simply meet the standards with 100 percent of the production within each family.  Also, unlike some other regulated motor vehicle sectors, we are not proposing that credits from over-compliance be able to be "banked" for use in a later model year, or to be "traded" among trailer manufacturers, since they would exacerbate the competitive issues, especially for small manufacturers, as discussed immediately below.  However, we are proposing to apply to trailers the provisions of Phase 1 for tractors that allow for the generation of a compliance deficit that could be resolved over several years.  Thus, a manufacturer that chose to use averaging, but by the end of the production year found that a trailer family's CO2 and fuel consumption values did not reach that year's standards, could carry a "deficit" that would need to be resolved by the third year following.
The availability of averaging options also has the potential to be a disadvantage to some companies in a competitive market that is highly customer-driven.  During the SBREFA process, several manufacturers expressed concern about their ability to manage their credit balances in a highly competitive market.  Many believe that they would have little ability to essentially force their customers to purchase the technology, especially if other manufacturers that had credits were able to sell trailers without the technology.  We see this as especially problematic for non-box trailers, which are much more likely to be produced by small businesses, and for which customers may have less interest in fuel savings technologies since they are less often used long-haul applications than are box trailers.  For these reasons, we are proposing averaging only for dry and refrigerated vans.
The agencies understand that averaging is unfamiliar to many trailer manufacturers and other stakeholders.  We have drafted a supplementary document that includes example scenarios to illustrate the concept of averaging for a hypothetical box trailer manufacturer.   Example adoption rates are provided for a standard compliance program (no averaging), an averaging program, and one that takes advantage of the design-based certification option.
One value of averaging that the agencies have historically cited in several other motor vehicle regulatory programs is that the availability of averaging provisions made it possible for the agencies to propose and enact more stringent standards than would otherwise have been appropriate, recognizing that the expected flexibility of averaging provisions would ease the path to compliance by the more challenged members of the industry.  In the case of trailer manufacturers, however, our decisions on the proposed stringency of the standards is essentially independent of the presence or absence of averaging, since, as discussed above, averaging provisions may have relatively less value to manufacturers in this customer-driven industry and we did not speculate about much or how little it might be used.
We also request comment on whether the burden of managing an averaging program could be more trouble than the flexibility is worth.  In the event that averaging were not allowed, the agencies would need to require that all trailers meeting specified characteristics meet a minimum stringency level without averaging.  If we were to finalize such non-averaging standards, manufacturers would still be allowed to select the appropriate technology package that best achieved their emission performance level, but they would not have the ability to accommodate customers that may request trailers that perform less well on an individual trailer basis.
It is also worth noting that the agencies are not proposing to allow any generation of early credits before MY 2018.  It is clear to us that small businesses would be less prepared to begin complying early than larger businesses, and that allowing large manufacturers to generate early credits that could be used later could put small businesses at a competitive disadvantage.  It does not appear to us that there would be a sufficient broader programmatic benefit from early credits to justify such an adverse impact on small businesses.
We request comment on this proposed averaging option, including whether the program should allow credit and deficit banking and credit trading, as well as on any other potential provisions that could provide compliance flexibility for trailer manufacturers while achieving the goals of the overall program.  Comments supporting averaging, banking, or trading should explain how these provisions would be valuable for trailer manufactures across the industry, including how the provisions would maintain a "level playing field."
Proposed SmartWay-Based Certification
Since many manufacturers have some experience with the SmartWay program, the agencies are proposing a gradual transition to the proposed approach that recognizes the parallel SmartWay Technology Program.  The agencies expect aerodynamic device manufacturers to continue to submit test data to SmartWay for verification.  Device manufacturers that also wish to have their technology available for trailer manufacturers to use in the Phase 2 program could, in parallel, submit their test data to EPA for pre-approval for Phase 2 (see Section IV.F.4).  The information obtained by EPA from the device manufacturers would include the technology name, a description of its proper installation procedure, and its corresponding delta CDA derived from the approved test procedures.  Any manufacturers that attained SmartWay verification prior to January 1, 2018 would be eligible to submit their previous data to EPA's Compliance Division for pre-approval, provided their test results come from SmartWay's 2014 test protocols that measure a delta CDA.  The protocols for coastdown, wind tunnel, and computational fluid dynamics analyses result in a CDA value.  Note that SmartWay's 2014 protocols allow SAE J1321 Type 2 track testing, which generates fuel consumption results, not CDA values.  The agencies request comment on whether we should pre-approve devices tested using SAE J1321 and also seek comment on an appropriate means of converting from the fuel consumption results of that test to the delta CDA values required for trailer compliance.
Beginning on January 1, 2018, EPA would require that device manufacturers that wish to seek approval of new technologies for trailer certification use one of the approved test methods for Phase 2 (i.e., coastdown, constant speed, wind tunnel or CFD) and the test procedures found in 40 CFR 1037.521.  Technologies that were pre-approved using SmartWay's 2014 Protocols would maintain their approved status until CY 2021.  After January 1, 2021, we are proposing that all pre-approved aerodynamic trailer technologies be tested using the Phase 2 test procedures.
Off-Cycle Technologies
The Phase 1 and proposed Phase 2 programs for tractors include provisions for manufacturers to request the use of off cycle technologies that are not recognized in GEM or were not in common use before MY 2010.  In the case of trailers, the agencies believe that any technologies that could improve CO2 and fuel consumption performance should be captured in the test protocols as proposed.  We are therefore not proposing a process to evaluate off-cycle trailer technologies.
Small Business Regulatory Flexibility Provisions
As a part of our small business obligations under the Regulatory Flexibility Act, EPA and NHTSA have considered additional flexibility provisions aimed at this segment of the trailer manufacturing industry.  EPA convened a Small Business Advocacy Review (SBAR) Panel as required by the Small Business Regulatory Enforcement Fairness Act (SBREFA), and much of the information gained and recommendations provided by this process form the basis of the flexibilities proposed.  As in previous rulemakings, our justification for including provisions specific to small businesses is that these entities generally have a greater degree of difficulty in complying with the standards compared to other entities.  Thus, as discussed below, we are proposing several regulatory flexibility provisions for small trailer manufacturers that we believe would reduce the burden on them while achieving the goals of the program.
We believe that the small business regulatory flexibilities discussed below and in Section XV.C could provide these entities with reduced compliance requirements and/or additional time to accumulate capital internally or to secure capital financing from lenders, and to acquire additional engineering and testing resources.
The agencies designed many of the proposed program elements and flexibility provisions available to all trailer manufacturers with the large fraction of small business trailer manufacturers in mind.  We believe the option to choose pre-approved aerodynamic devices would significantly reduce the compliance burden and eliminate the requirement for all manufacturers to perform testing.  Additionally, the proposed design-based certification provisions for non-box and non-aero box trailers would further reduce the compliance burden by providing manufacturers the option to certify without the use of GEM.
As noted above, the small trailer manufacturers raised concerns that their businesses could be harmed by provisions allowing averaging, banking, and trading of emissions and fuel consumption performance, since they would not be able to generate the same volume of credits as large manufacturers.  The agencies are proposing not to include banking and trading provisions in any part of the program, and are limiting the option to average to manufacturers of dry and refrigerated box trailers.  Since a majority of non-box trailer manufacturers are small businesses, we believe a requirement of tire technologies for all non-box trailers creates the most uniformity in requirements between manufacturers and reduces the compliance burden by eliminating the use of GEM.
In addition to the provisions offered to trailer manufacturers of all sizes, the agencies are proposing or requesting comment on several additional provisions designed specifically to ease compliance burdens on small trailer manufacturers.  For all small business trailer manufacturers, the agencies propose a one-year delay in the beginning of implementation of the program, until MY 2019.  We believe (subject to consideration of public comment) that this will allow small businesses additional needed lead-time to make the proper staffing adjustments and process changes, and possibly add new infrastructure to meet the requirements.  We also request comment about where there may be circumstances in later stages of the program, when the stringency of the standards increase in MY 2021 and 2024, when a similar 1-year delay in implementation could be warranted for small trailer manufacturers.
As mentioned previously, we are proposing to offer averaging provisions for manufacturers of dry and refrigerated box trailers only.  We recognize that the small box trailer manufacturers may not be able to fully take advantage of averaging and may be at a competitive disadvantage with larger manufacturers with larger sales volumes and more diverse product lines.  We request comment on additional provisions that could ease the potential harm to and/or incentivize small business participation in an averaging program.
For small business manufacturers of box trailers, the agencies propose that if the proposed provisions allowing EPA pre-approval of aerodynamic devices (which is proposed as an interim program) were to end, small business trailer manufacturers could continue to use pre-approved devices and avoid independent testing.  Furthermore, we are proposing to end the interim design-based certification option after MY 2023.  We request comment on whether this option should be extended beyond MY 2023 for small manufacturers.
The agencies also request comment on provisions for small manufacturers that might face a situation where the technologies needed for compliance are unavailable.  This could be a particular concern for small business non-box and non-aero box trailers that require the use of LRR tires and ATI systems.  We request that trailer manufacturers as well as tire and aerodynamic technology manufacturers provide information regarding the current projected availability of the technologies that trailer manufacturers can use to meet our proposed standards.

Class 2b-8 Vocational Vehicles
Summary of Phase 1 Vocational Vehicle Standards
Class 2b-8 vocational vehicles include a wide variety of vehicle types, and serve a vast range of functions. Some examples include service for urban delivery, refuse hauling, utility service, dump, concrete mixing, transit service, shuttle service, school bus, emergency, motor homes, and tow trucks.  In the HD Phase 1 Program, the agencies defined Class 2b-8 vocational vehicles as all heavy-duty vehicles that are not included in the Heavy-duty Pickup Truck and Van or the Class 7 and 8 Tractor categories.  In effect, the rules classify everything that is not a combination tractor or a pickup truck or van as a vocational vehicle. Class 2b-8 vocational vehicles and their engines emit approximately 20 percent of the GHG emissions and burn approximately 21 percent of the fuel consumed by today's heavy-duty truck sector.
Most vocational vehicles are produced in a two-stage build process, though some are built from the "ground up" by a single entity.  In the two-stage process, the first stage sometimes is completed by a chassis manufacturer that also builds its own proprietary components such as engines or transmissions.  This is known as a vertically integrated manufacturer. The first stage can also be completed by a chassis manufacturer who procures all components, including the engine and transmission, from separate suppliers.  The product completed at the first stage is generally either a stripped chassis, a cowled chassis, or a cab chassis. A stripped chassis may include a steering column, a cowled chassis may include a hood and dashboard, and a cab chassis may include an enclosed driver compartment.  Many of the same companies that build Class 7 and 8 tractors also sell vocational chassis in the medium heavy- and heavy heavy-duty weight classes. Similarly, some of the companies that build Class 2b and 3 pickups and vans also sell vocational chassis in the light heavy-duty weight classes.
The second stage is typically completed by a final stage manufacturer or body builder, which installs the primary load carrying device or other work-related equipment, such as a dump bed, delivery box, or utility boom.  There are over 200 final stage manufacturers in the U.S., most of which are small businesses.  Even the large final stage manufacturers are specialized, producing a narrow range of vehicle body types. These businesses also tend to be small volume producers. In 2011, the top four producers of truck bodies sold a total of 64,000 units, which is about 31 percent of sales in that year.  In that same year, 74 percent of final stage manufacturers produced less than 500 units.
The businesses that act both as the chassis manufacturer and the final stage manufacturer are those that build the vehicles from the "ground up." These entities generally produce custom products that are sold in lower volumes than those produced in large commercial processes. Examples of vehicles produced with this build process would include fire apparatus and transit buses.
  The diversity in the vocational vehicle segment can be primarily attributed to the variety of customer needs for specialized vehicle bodies and added equipment, rather than to the chassis.  For example, a body builder can build either a Class 6 bucket truck or a Class 6 delivery truck from the same Class 6 chassis.  The aerodynamic difference between these two vehicles due to their bodies would lead to different in-use fuel consumption and GHG emissions.  However, the baseline fuel consumption and emissions due to the components included in the common chassis (such as the engine, drivetrain, frame, and tires) would be the same between these two types of vehicles.