[Federal Register Volume 83, Number 31 (Wednesday, February 14, 2018)]
[Notices]
[Pages 6718-6722]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-03033]


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DEPARTMENT OF TRANSPORTATION

Federal Motor Carrier Safety Administration

[Docket No. FMCSA-2016-0167]


Parts and Accessories Necessary for Safe Operation, Lamps and 
Reflective Devices; Application for an Exemption From STEMCO LP

AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT.

ACTION: Notice of final disposition; grant of application for 
exemption.

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SUMMARY: The Federal Motor Carrier Safety Administration (FMCSA) 
announces its decision to grant STEMCO LP's (STEMCO) application for a 
limited 5-year exemption to allow motor carriers to operate certain 
commercial motor vehicles (CMVs) that are equipped with STEMCO's 
TrailerTail[supreg] aerodynamic device with rear identification lamps 
and rear clearance lamps that are mounted lower than currently 
permitted by the Agency's regulations. The Federal Motor Carrier Safety 
Regulations (FMCSRs) require rear identification lamps and rear 
clearance lamps to be located ``as close as practicable to the top of 
the vehicle.'' While the TrailerTail[supreg] aerodynamic device is 
currently mounted slightly below the roof of the vehicle, STEMCO states 
that this offset prevents the device from delivering the maximum 
available fuel economy benefit as opposed to mounting it flush with the 
top of the vehicle which may block the visibility of the rear 
identification lamps and rear clearance lamps. The Agency has 
determined that locating the rear identification lamps and rear 
clearance lamps lower on the trailers and semitrailers, mounted at the 
same level as the stop lamps, tail lamps, and turn signals will 
maintain a level of safety that is equivalent to, or greater than, the 
level of safety achieved without the exemption.

FOR FURTHER INFORMATION CONTACT: Mr. Jose Cestero, Vehicle and Roadside 
Operations Division, Office of Bus and Truck Standards and Operations, 
MC-PSV, (202) 366-5541; Federal Motor Carrier Safety Administration, 
1200 New Jersey Avenue SE, Washington, DC 20590-0001.

SUPPLEMENTARY INFORMATION:

Background

    Pursuant to 49 CFR part 381, FMCSA has authority to grant 
exemptions from certain Federal Motor Carrier Safety Regulations 
(FMCSRs). FMCSA must publish a notice of each exemption request in the 
Federal Register (49 CFR 381.315(a)). The Agency must provide the 
public with an opportunity to inspect the information relevant to the 
application, including any safety analyses that have been conducted. 
The Agency must also provide an opportunity for public comment on the 
request.
    The Agency reviews the safety analyses and the public comments and 
determines whether granting the exemption would likely achieve a level 
of safety equivalent to or greater than the level that would be 
achieved by the current regulation (49 CFR 381.305(a)).
    The decision of the Agency must be published in the Federal 
Register (49 CFR 381.315(b)). If the Agency denies the request, it must 
state the reason for doing so. If the decision is to grant the 
exemption, the notice must specify the person or class of persons 
receiving the exemption and the regulatory provision or provisions from 
which an exemption is granted. The notice must specify the terms and 
conditions of the exemption, as well as its effective period (up to 5 
years). The exemption may be renewed (49 CFR 381.315(c) and 49 CFR 
381.300(b)).

STEMCO Application for Exemption

    STEMCO, on behalf of motor carriers utilizing its 
TrailerTail[supreg] aerodynamic devices, applied for an exemption from 
49 CFR 393.11 to allow rear identification lamps and rear clearance 
lamps to be mounted lower than currently permitted by the Agency's 
regulations.
    Table 1 of section 393.11, ``Required lamps and reflectors on 
commercial motor vehicles,'' specifies the requirements for lamps, 
reflective devices and associated equipment by the type of CMV. All 
CMVs manufactured on or after December 25, 1968, must, at a minimum, 
meet the applicable requirements of Federal Motor Vehicle Safety 
Standard (FMVSS) No. 108, ``Lamps, reflective devices, and associated 
equipment,'' in effect at the time of manufacture of the vehicle. Rear 
identification lamps must be mounted as close as practicable to the top 
of the vehicle. One lamp must be as close as practicable to the 
vertical centerline and one on each side of the center lamp with the 
lamp centers spaced not less than 6 inches or more than 12 inches 
apart, and all on the same level. One rear clearance lamp must be 
located on each side of the vertical centerline of the vehicle to 
indicate overall width, both of which must be on the same level and as 
high as practicable.
    In February 2015, STEMCO purchased ATDynamics and its 
TrailerTail[supreg] product line, a collapsible

[[Page 6719]]

boat tail technology that improves the rear aerodynamic shape of CMV 
trailers. In its application, STEMCO states that motor carriers are 
evaluating the TrailerTail[supreg] rear aerodynamic device to help meet 
(1) proposed standards from the U.S. Environmental Protection Agency 
(EPA) and the Department of Transportation's National Highway Traffic 
Safety Administration (NHTSA) that would establish the next phase of 
greenhouse gas (GHG) emissions and fuel efficiency standards for 
medium- and heavy duty vehicles,1 2 and (2) the California 
Air Resources Board (CARB) Tractor-Trailer Greenhouse Gas Regulation 
for dry van and refrigerated van type trailers that has been in effect 
since 2010.
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    \1\ On October 25, 2016, EPA and NHTSA jointly published a final 
rule establishing rules for a comprehensive Phase 2 Heavy-Duty (HD) 
National Program that will reduce greenhouse gas (GHG) emissions and 
fuel consumption from new on-road medium- and heavy-duty vehicles 
and engines, helping to address the challenges of global climate 
change and energy security (81 FR 73478). NHTSA's fuel consumption 
standards and EPA's carbon dioxide (CO2) emission 
standards are tailored to each of four regulatory categories of 
heavy-duty vehicles: Combination tractors; trailers used in 
combination with those tractors; heavy-duty pickup trucks and vans; 
and vocational vehicles. The rule also includes separate standards 
for the engines that power combination tractors and vocational 
vehicles.
    \2\ In response to letters submitted by the Truck Trailer 
Manufacturers Association seeking reconsideration of the October 
2016 final rule, both EPA and NHTSA decided on August 17, 2017 to 
conduct additional rulemaking on the issues of GHG emissions and 
fuel efficiency standards for medium- and heavy-duty vehicles.
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    For newly manufactured trailers, STEMCO states that the 
TrailerTail[supreg] top panel is mounted 1.5-3.5 inches below the roof 
of the trailer in order to comply with the FMVSS No. 108 and FMCSR 
mounting location requirements for rear identification and clearance 
lamps. However, STEMCO states:

    This inset creates an unaerodynamic gap as airflow transitions 
from the trailer roof onto the TrailerTail panels and has prevented 
TrailerTails from delivering the maximum available fuel economy 
benefit. Wind tunnel flow visualization highlights the contrast in 
airflow between flush and inset panels and our own internal testing 
estimates an additional 0.14 delta CDA (measured drag 
area) gain and 70 million gallons of annual diesel fuel savings can 
be achieved simply by installing TrailerTails flush with the trailer 
roof. In order to evaluate the actual performance of flush mounted 
TrailerTail aerodynamic systems on actual fleet based fuel economy, 
it is necessary to request relief from the location requirements for 
upper identification lamps and rear clearance lamps on commercial 
van trailers and box trucks. Additionally, these lower clearance and 
identification lamp locations will pave the way for the commercial 
launch of collapsible boat tails for roll door box trailers, where 
the rear upper header is a critical mounting location of boat tail 
components.

    In support of its application, STEMCO states that ``The relocation 
of the rear identification lamps and rear clearance lamps to a lower 
location on the trailer or box truck are equivalent to the current 
required lamp location on a flatbed trailer or intermodal chassis, so 
no safety impact is anticipated.'' In addition, according to the 
application:

    STEMCO believes that there will be no safety impact from the 
relocation of both the rear identification lamps and the rear 
clearance lamps to a location on an approximate horizontal plane 
with other rear lamps. NHTSA issued legal interpretations from 1968 
until approximately 1999 to trailer manufacturers to allow the lower 
mounting location for rear identification lamps and rear clearance 
lamps when there was no ``practicable'' means of installing the 
lamps ``as close as practicable to the top of the vehicle.'' NHTSA 
subsequently issued an interpretative rule on April 5, 1999, 64 FR 
16358, suggesting that trailer manufacturers could no longer mount 
lamps at the lower location as narrow lamps were now readily 
available, and NHTSA would no longer defer to a manufacturer's 
subjective determination of practicability for locating lamps in the 
rear upper header location on van trailers and box trucks. However, 
NHTSA noted in that same Notice that they did not intend to bring 
enforcement actions based on this interpretive rule immediately. 
Subsequently, trailer manufacturers continued to manufacture van 
trailers and box trucks with the rear identification lamps and rear 
clearance lamps mounted lower on the vehicles on an approximate 
horizontal plane with the other required lamps.

    STEMCO states that without the exemption, it will be unable to 
verify fleet performance of a higher performance TrailerTail[supreg] 
design that is expected to provide the maximum available fuel economy 
benefit that may be necessary in order to meet future fuel efficiency 
requirements.

Comments

    On June 10, 2016, FMCSA published a notice of the STEMCO 
application and asked for public comment (81 FR 37662). The Agency 
received comments from the American Trucking Associations (ATA), the 
Transportation Safety Equipment Institute (TSEI), and Wabash National 
Corporation (Wabash).
    ATA supported STEMCO's application, stating:

    Efficiency-improving technologies include tractor aerodynamics, 
fuel-efficient tires, idle reduction equipment, speed governors, use 
of lighter weight equipment and aerodynamic trailer skirts and 
tails. ATA supports efforts to improve fuel efficiency and actions 
to improve coordination between federal agencies to advance fuel 
efficiency in the trucking industry . . .
    According to the U.S. Environmental Protection Agency's SmartWay 
program trailer tails can improve heavy truck fuel efficiency by 
five percent. STEMCO's wind tunnel testing suggests that an 
additional 0.14 percent improvement can be achieved if its trailer 
tail is mounted flush with the top of the trailer. In order to 
verify this finding, STEMCO should be allowed to test the device in 
an actual on-road environment with a fleet of heavy trucks.
    As FMCSA is aware, there are many trailer types throughout the 
motor carrier industry. Some trailers, like flatbeds and intermodal 
chassis, are required to have lighting systems on the rear frame of 
the trailer to comply with FMVSS 108 and 49 CFR 393.11. And, since 
these trailer types have no upper frame or doors at the rear of the 
trailer, it is not possible for them to have marker or 
identification lamps similar to those required on van trailers. 
Unless the FMCSA has research and data showing the marker and 
identification lights on a van trailer improve safety over and above 
the light configuration on flatbed trailers and/or intermodal 
chassis, etc., the agency should grant the exemption for evaluation 
purposes.

    TSEI and Wabash both expressed concerns that allowing the 
identification and clearance lamps to be mounted lower than currently 
required, on the same horizontal plane with the stop, turn, and tail 
lamps, may not maintain a level of safety that is equivalent to or 
greater than the level of safety without the exemption because other 
motorists might not be able to adequately distinguish large trucks and 
trailers from other passenger other vehicles. TSEI stated:

    STEMCO's application does not appear to take into account the 
important role signal lighting plays in vehicle conspicuity. The 
signal lighting on heavy duty vehicles does more than provide 
``intention'' (e.g., stop or turn) signals; it also provides 
conspicuity (e.g., conspicuity triangle created between the 
identification lamp cluster and the stop/tail/turn lamps. The Agency 
should be cautious about infringing upon the longstanding 
relationship between the signal and conspicuity aspects of heavy 
duty lighting in the absence of supporting data concerning the 
effects on trailer conspicuity.
    TSEI acknowledges that many vehicles utilize low mounting 
positions due to the construction of the vehicle. Presumably, the 
practicability language in FMCSR and FMVSS accounts for differences 
in mounting positions. As NHTSA has explained, ``[s]ince the various 
types of trailers differ from one another in their configuration, 
NHTSA believes that the method of compliance that may be appropriate 
for one type may not be for another. For example, van-type trailers 
have distinct rectangular side and rear perimeters to which 
conspicuity enhancing materials could be easily applied, while tank-
type, platform trailers, or others do not.'' 56 FR 63475 (Dec. 4, 
1991) (Notice of proposed rulemaking regarding increasing 
conspicuity of trailers which have an overall width of 80 inches or 
more to enhance the likelihood of

[[Page 6720]]

their detection at night and conditions of reduced visibility).
    But acknowledging these differences does not demonstrate that 
lowering the mounting position to accommodate an aerodynamic device 
would not adversely affect safety. Because STEMCO has not provided 
any data on the safety impact of lowering the height of rear 
identification lamps and rear clearance lamps, STEMCO has not 
provided a basis for evaluating their statement that the lower 
placement will not adversely affect safety, particularly with 
respect to the trailers' conspicuity.

    Similarly, Wabash stated:

    The ability of motorists to distinguish large trucks and 
trailers from passenger vehicles is an essential component of crash 
avoidance because of size, maneuvering, and the speed differences 
between the two types of vehicles. High mounted identification lamps 
uniquely identify large trucks and wide trailers and do so with the 
longest possible sight preview of the lamps. Clearance lamps show 
the overall width of the vehicle to alert drivers of its large size. 
NHTSA has already concluded that, if rear identification lamps were 
lowered, the purpose of uniquely identifying large vehicles with the 
longest possible sight preview of the lamps would be compromised. As 
the mounting height of identification lamps is lowered, the time 
that nearby drivers have to identify the vehicle as a large truck, 
including drivers not located immediately behind the truck, is 
reduced and is contrary to the safety objective of the mounting 
height requirement.
    NHTSA's conclusions regarding the safety implications of 
unnecessarily lowering the mounting height for rear identification 
lamps and rear clearance lamps are supported by a recent FMCSA 
sponsored study which observed that, with respect to large vehicles, 
``[p]assive crash avoidance can be accomplished by the conspicuity 
of the vehicle, that is, the extent to which the vehicle is readily 
perceived by other road users. In terms of the physical and 
mechanical systems of the vehicle, conspicuity is primarily 
accomplished through the light system on the vehicle. The light 
system includes tail and top lamps, marker and identification lamps, 
as well as the reflective tape systems on trailers.

    TSEI noted that if the exemption is granted, vehicle and trailer 
manufacturers would still be required to comply with the requirements 
of FMVSS No. 108 (install the identification and clearance lamps as 
high as practicable), and repair businesses would not be permitted to 
move the lamps to a lower position because Title 49, U.S. Code 30122(b) 
of the Motor Vehicle Safety Act ``prohibits a manufacturer, 
distributor, dealer, or motor vehicle repair business from knowingly 
making inoperative any part of a device or element of design installed 
on or in a motor vehicle in compliance with an applicable motor vehicle 
safety standard.'' Because of the above, TSEI expressed concerns that 
some fleets and small-scale operators my not have the technical 
expertise to change the positioning of the identification and clearance 
lamps to a lower position.
    TSEI also noted that S6.2.2 of FMVSS No. 108 states ``If any 
required lamp or reflective device is obstructed by motor vehicle 
equipment (e.g., mirrors, snow plows, wrecker booms, backhoes, winches, 
etc.) including dealer installed equipment, and cannot meet the 
applicable photometry and visibility requirements, the vehicle must be 
equipped with an additional lamp or device of the same type which meet 
all applicable requirements of this standard, including photometry and 
visibility.'' TSEI stated ``STEMCO could equip vehicles with additional 
lamps or devices that meet FMVSS 108 to accommodate for the lamps that 
would be obstructed by the aerodynamic device. Such an approach would 
not require an exemption.''
    Wabash stated that it is possible--and practicable--to attach an 
aerodynamic tail device to the rear top sill of a trailer without 
blocking rear identification lamps and rear clearance lamps while still 
meeting the new GHG regulations. Wabash stated:

    Wabash's innovative aerodynamic tail devices--which are known as 
the AeroFin\TM\ and AeroFin\TM\ XL--can be attached to the rear top 
sill of the trailer without blocking the rear identification lamps 
and rear clearance lamps. Further, STEMCO's argument that the 
exemption is needed to meet the current requirements of the 
California Air Resource Board (CARB) Tractor-trailer Greenhouse Gas 
regulations and proposed Greenhouse Gas Phase 2 regulations is 
unpersuasive. By using the AeroFin\TM\ in combination with certain 
of its trailer aerodynamic technologies, Wabash has achieved 
improvement of 9% or greater in fuel economy. In addition, the 
AeroFin\TM\ XL is CARB compliant. Again, technological advancements 
have made it possible for manufacturers to meet the safety 
objectives of FMVSS 108 without compromising other performance 
related considerations.

FMCSA Analysis

    FMCSA agrees that it is important for motorists to be able to 
readily distinguish large trucks and trailers from other passenger 
vehicles. FMVSS No. 108 and section 393.11 of the FMCSRs ensure this by 
requiring large vehicles to be equipped with a combination of lights, 
reflectors, and conspicuity treatments that help indicate the overall 
height, width, and length of these vehicles. Specifically, all CMVs 
manufactured on or after December 25, 1968, must, at a minimum, meet 
the applicable requirements of FMVSS No. 108 in effect at the time of 
manufacture of the vehicle. The purpose of FMVSS No. 108 is to reduce 
crashes and deaths and injuries from crashes, by providing adequate 
illumination of the roadway, and by enhancing the conspicuity of motor 
vehicles on the public roads so that their presence is perceived and 
their signals understood, both in daylight and in darkness or other 
conditions of reduced visibility. FMVSS No. 108 specifies requirements 
for original and replacement lamps, reflective devices, and associated 
equipment. The standard applies to passenger cars, multipurpose 
passenger vehicles, trucks, buses, trailers, and motorcycles.
    Specifically with respect to clearance lamps and identification 
lamps, all (1) trucks and buses 80 inches or more in width, (2) 
semitrailers and full trailers 80 inches or more in width (except 
converter dollies), and (3) pole trailers must be equipped with:
     Two red clearance lamps, one on each side of the vertical 
centerline of the vehicle, mounted as high as practicable to indicate 
the overall width of the vehicle; and
     A group of three red identification lights on the rear of 
the vehicle, mounted as close as practicable to the top of the vehicle. 
One lamp is required to be mounted as close as practicable to the 
vertical centerline of the vehicle, and one on each side with lamp 
centers spaced not less than 6 inches or more than 12 inches apart.
    The grouping of three identification lamps on the top rear of large 
vehicles is intended to uniquely identify large vehicles with the 
longest sight preview possible. On February 5, 2003, NHTSA denied a 
petition for rulemaking from Sierra Products, Inc. (Sierra), which--
among other things--requested that NHTSA amend FMVSS No. 108 to require 
the identification lights to be mounted at eye height on heavy trucks 
(68 FR 5863). In denying Sierra's petition, NHTSA stated ``As the 
mounting height of identification lamps is lowered, the time that 
nearby drivers will have to identify the vehicle, as a heavy truck will 
lessen. This is contrary to the intent of the requirement. On the other 
hand, the mounting height of identification lamps has been long 
established to be `as high as practicable.' This is to make nearby 
drivers aware of the vehicle's size. If these lamps were lowered to eye 
level, approaching drivers may not be able to distinguish large 
commercial vehicles from passenger vehicles.'' [Emphasis added.]
    Notwithstanding the above, FMCSA notes that the three 
identification lamps are not the only means by which drivers

[[Page 6721]]

are ``able to distinguish large commercial vehicles from passenger 
vehicles,'' as stated in NHTSA's denial of the petition from Sierra. 
While FMCSA agrees that mounting identification lamps ``as high as 
practicable'' provides approaching motorists maximum time to identify a 
CMV, and that lowering the mounting location of the identification 
lamps reduces that time, FMVSS No. 108 (and, by incorporation, section 
393.11 of the FMCSRs) also requires the rear of all trailers and 
semitrailers to be equipped with conspicuity materials (a strip of 
alternating red and white retroreflective sheeting or reflex 
reflectors) installed across both:
    (1) The full width of the trailer, as close to the extreme edges as 
practicable, and as close to practicable to not less than 375 mm (14.77 
in) and not more than 1525 mm (60.05 in) above the road surface at the 
centerline with the trailer at curb weight, and
    (2) The full width of the horizontal member of the rear underride 
protection device required by FMVSS No. 224, ``Rear impact 
protection.'' The horizontal member is required to extend to within 100 
mm (4 in) of the side extremity of the vehicle, and be located not more 
than 560 mm (20.05 in) above the ground at any point.
    The presence of these two separate conspicuity treatments on the 
rear of all trailers and semitrailers, consisting of alternating red 
and white retroreflective material or reflex reflectors, serves as a 
clear indication to the motoring public that the vehicle is a large 
commercial vehicle as opposed to a passenger car. While these 
conspicuity treatments are not located at or near the very top of the 
trailer or semitrailer, FMCSA believes that they provide a very 
distinctive visual pattern on the rear of trailers and semitrailers 
that easily enables motorists to be aware that they are approaching a 
large vehicle.\3\
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    \3\ FMCSA also notes that, per STEMCO's product literature, each 
side component of its aerodynamic device has red and white 
conspicuity tape applied to the outward face of the device, further 
enhancing the visibility of the vehicle.
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    It is important to note that STEMCO is proposing that the required 
clearance and identification lights be relocated lower on vehicles 
using the aerodynamic devices, and is not simply requesting an 
exception to the regulation because the required lights are obscured by 
the device. FMCSA believes that relocating the lamps to a lower 
position is an acceptable approach and ensures an equivalent level of 
safety for two separate reasons. First, and as STEMCO notes in its 
application, FMVSS No. 108 and section 393.11 of the FMCSRs permit the 
clearance and identification lamps to be mounted lower on flatbed 
trailers and intermodal chassis simply because there is no other 
position to mount the lamps due to the vehicle designs. FMCSA does not 
believe that locating the clearance and identification lamps in the 
same manner on trailers and semitrailers using STEMCO's aerodynamic 
devices will pose an unreasonable risk, especially given the 
conspicuity requirements discussed above. Second, and as noted by TSEI 
in its comments, S6.2.2 of FMVSS No. 108 directly addresses vehicle 
designs whereby required lamps or reflective devices are obscured by 
motor vehicle equipment such as ``mirrors, snow plows, wrecker booms, 
backhoes, winches,'' which would also include STEMCO's aerodynamic 
devices. In these instances, S6.2.2 of FMVSS No. 108 requires the 
vehicle to ``be equipped with an additional lamp or device of the same 
type which meet all applicable requirements of this standard, including 
photometry and visibility.'' This is exactly what STEMCO is proposing 
to do--to install the same clearance and identification lamps, but in a 
lower position on the vehicle.
    Regarding TSEI's concern that some fleets and small-scale operators 
may not have the technical expertise to change the positioning of the 
identification and clearance lamps to a lower position, FMCSA notes 
that it is the responsibility of each motor carrier to ensure that its 
vehicles fully comply with the FMCSRs at all times (see 49 CFR 
393.1(c)), which includes the terms and conditions of this temporary 
exemption. As such, if a motor carrier chooses to use STEMCO's device, 
it must ensure that the required lights are properly moved and are 
fully operational at all times.
    FMCSA acknowledges Wabash's comment that it has developed a 
solution whereby its aerodynamic device can be fitted to a trailer 
without obscuring the required clearance and identification lights 
located at the top of the trailer. While Wabash has designed a solution 
that does not require relief from the current standards, STEMCO has 
applied for a temporary exemption in order to test an alternative 
design based on its contention that use of that design will provide an 
equivalent or greater level of safety than without the exemption. 
Because of reasons discussed above, FMCSA believes that an equivalent 
level of safety will be maintained.
    While FMVSS No. 108 and section 393.11 of the FMCSRs require the 
two conspicuity treatments to be installed on the rear of trailers and 
semitrailers, FMCSA notes that neither of the conspicuity treatments is 
required to be installed on single unit trucks (box trucks). For this 
reason, FMCSA believes that it is appropriate to limit the use of 
STEMCO's aerodynamic device, when mounted at the top of the vehicle and 
obscuring the clearance and identification lights, to trailers and 
semitrailers only at this time.

FMCSA Decision

    FMCSA has evaluated the STEMCO exemption application. For the 
reasons discussed above, the Agency believes that granting the 
temporary exemption to allow rear identification lamps and rear 
clearance lamps to be located lower on trailers and semitrailers, 
mounted at the same level as the stop lamps, tail lamps, and turn 
signals, will maintain a level of safety that is equivalent to, or 
greater than, the level of safety achieved without the exemption.

Terms and Conditions for the Exemption

    The Agency hereby grants the exemption for a 5-year period, 
beginning February 14, 2018 and ending February 14, 2023. During the 
temporary exemption period, motor carriers will be allowed to mount 
STEMCO's TrailerTail[supreg] aerodynamic device at the top of trailers 
and semitrailers, provided that the rear clearance and identification 
lights are mounted at the same level as the stop lamps, tail lamps, and 
turn signals. The exemption will be valid for 5 years unless rescinded 
earlier by FMCSA. The exemption will be rescinded if: (1) Motor 
carriers and/or CMVs fail to comply with the terms and conditions of 
the exemption; (2) the exemption has resulted in a lower level of 
safety than was maintained before it was granted; or (3) continuation 
of the exemption would not be consistent with the goals and objectives 
of 49 CFR part 381.
    Interested parties possessing information that would demonstrate 
that motor carriers using trailers or semitrailers with STEMCO's 
TrailerTail[supreg] aerodynamic device are not achieving the requisite 
statutory level of safety should immediately notify FMCSA. The Agency 
will evaluate any such information and, if safety is being compromised 
or if the continuation of the exemption is not consistent with 49 CFR 
part 381, will take immediate steps to revoke the exemption.

Preemption

    In accordance with 49 U.S.C. 31315(d), as implemented by 49 CFR 
381.600, during the period this

[[Page 6722]]

exemption is in effect, no State shall enforce any law or regulation 
applicable to interstate commerce that conflicts with or is 
inconsistent with this exemption with respect to a firm or person 
operating under the exemption. States may, but are not required to, 
adopt the same exemption with respect to operations in intrastate 
commerce.

    Issued on: February 8, 2018.
Cathy F. Gautreaux,
Deputy Administrator.
[FR Doc. 2018-03033 Filed 2-13-18; 8:45 am]
BILLING CODE 4910-EX-P