Advance notice of proposed rulemaking (ANPRM).
CFR Part: "49 CFR Part 571"
RIN Number: "RIN 2127-AL37"
Citation: "84 FR 51076"
Document Number: "Docket No. NHTSA-2019-0093"
Page Number: "51076"
SUMMARY: The Moving Ahead for Progress in the 21st Century Act of 2012 directs NHTSA to initiate a rulemaking proceeding to amend Federal Motor Vehicle Safety Standard No. 208, "Occupant crash protection," to require a seat belt use warning system for rear seats. NHTSA initiated a rulemaking proceeding in 2013, and as it continues with this proceeding NHTSA is seeking public comment on a variety of issues related to a requirement for a rear seat belt warning system. NHTSA seeks comment on, among other things, potential requirements for such systems, the vehicles to which they should apply, their effectiveness, the likely consumer acceptance, and the associated costs and benefits.
You should submit your comments early enough to be received not later than
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Table of Contents
I. Executive Summary 4 II. Background 7 III. Regulatory and Legislative History 13 IV.
NHTSA Researchon Effectiveness and Acceptance of Seat Belt Warnings 18 V. NHTSA's Statutory Authority21 VI. Issues on Which NHTSA Seeks Information From the Public 22 A. Potential Specifications for a Required Rear Belt Warning System 22 B. Applicability 39 C. Effectiveness 40 D. Consumer Acceptance 43 E. Technological and Economic Feasibility 45 F. Benefits and Costs 46 G. Safety Act Criteria 46 H. Non-Regulatory Alternatives 46 I. Removing the Driver's Seat Belt Warning Audible Signal Duration Upper Limit 47 VII. Regulatory Notices 48 VIII. Public Comment 49
I. Executive Summary The Moving Ahead for Progress in the 21st Century Act of 2012 (MAP-21) directs the
Using a seat belt is one of the most effective actions a motor vehicle occupant can take to prevent death and injury in a crash. Seat belts are effective in most types of crashes. Research has found that seat belts greatly reduce the risk of fatal and non-fatal injuries, compared to the risk faced by unrestrained occupants. Unbelted occupants are overrepresented in fatal crashes. For rear seat occupants, seat belts reduce the risk of fatality by 55 percent (for passenger cars) and 74 percent (for light trucks and vans). /1/
FOOTNOTE 1 Donna Glassbrenner &
Although seat belt use has steadily increased over the past few decades, usage rates for rear belts have consistently been below those for the front seats. According to data from
Seat belt warning systems encourage seat belt use by reminding unbuckled occupants to fasten their belts and/or by informing the driver that an occupant is unbelted, so that the driver can request the unbelted occupant to fasten their seat belt. FMVSS No. 208 requires a seat belt warning system for the driver's seat, but not other seating positions. Most currently-produced vehicles also have a seat belt warning for the front outboard passenger seat, although FMVSS No. 208 does not require this. About 13 percent of model year (MY) 2019 vehicles sold in
Euro New Car Assessment Program (NCAP) /2/ awards points for front and rear seat belt reminder systems (SBRSs) as part of their Safety Assist score. Their assessment protocol dictates the requirements for the activation and duration of the warning signals for front and rear seats including a change of status warning.
In 2007, Public Citizen and Advocates for Highway and Auto Safety petitioned NHTSA to amend FMVSS No. 208 to require a seat belt warning system for rear seats on passenger cars and multipurpose passenger vehicles (MPVs) with a gross vehicle weight rating (GVWR) of 4,536 kilograms (10,000 pounds) or less. The petitioners stated that rear seat belt warnings would save hundreds of lives each year and that a large percentage of the lives saved would be children. In 2010, the agency published a Request for Comments (RFC) on the petition. The RFC discussed the agency's research and findings regarding rear seat belt warnings and solicited comments.
FOOTNOTE 3 This requires, among other things, that a federal motor vehicle safety standard be practicable, meet the need for motor vehicle safety, and be stated in objective terms. END FOOTNOTE
FOOTNOTE 4 Below we seek comment on possible sample selection bias (because these survey respondents were drivers of vehicles equipped with rear seat belt warning systems). END FOOTNOTE
NHTSA has granted Public Citizen and Advocates for Highway and Auto Safety's petition. In accordance with that grant and continuing with the proceeding that MAP-21 required to be initiated, the agency is publishing this Advance Notice of Proposed Rulemaking. In it, we seek comment on a variety of issues related to a requirement for a rear seat belt warning system, including potential requirements for such systems, the vehicles to which they should apply, their effectiveness, the likely consumer acceptance, and the associated costs and benefits. This document also provides relevant background information, such as up-to-date information on rear seat belt warning systems that are currently available on some new motor vehicles. The document also seeks comment on removing the 8-second maximum duration for the driver's seat belt warning specified in FMVSS No. 208, S7.3; this amendment would reflect MAP-21's repeal of the statutory limitation that was the basis for this provision.
Section 31503 of the Moving Ahead for Progress in the 21st Century Act (MAP-21) (Pub. L. 112-141) directs the Secretary /5/ of Transportation to initiate a rulemaking proceeding to amend Federal Motor Vehicle Safety Standard (FMVSS) No. 208, "Occupant crash protection" (49 CFR 571.208) to require a seat belt use warning system for rear seats. /6/ As it continues with this proceeding, the
FOOTNOTE 5 Authority has been delegated to NHTSA. END FOOTNOTE
FOOTNOTE 6 Seat belt use warning systems may also be referred to in this document as seat belt "warning systems" or seat belt "reminder" systems. END FOOTNOTE
Using a seat belt is one of the most effective actions a motor vehicle occupant can take to prevent death and injury in a crash. /7/ Seat belts protect occupants in various ways. They prevent occupants from being ejected from the vehicle; provide "ride-down" by gradually decelerating the occupant as the vehicle deforms and absorbs energy; and reduce the occurrence of occupant contact with harmful interior surfaces and other occupants. /8/ Seat belts are effective in most types of crashes. Research has found that seat belts greatly reduce the risk of fatal and non-fatal injuries, compared to the risk faced by unrestrained occupants. Unbelted occupants are overrepresented in fatal crashes. /9/ Seat belts reduce the risk of fatality for rear outboard occupants by 54 percent (passenger cars) and 75 percent (light trucks and vans), and for center occupants, by 58 percent (passenger cars) and 75 percent (light trucks and vans). /10/
FOOTNOTE 7 68 FR 46262 (
FOOTNOTE 8 Charles J. Kahane. 2015. Lives Saved by Vehicle Safety Technologies and Associated Federal Motor Vehicle Safety Standards, 1960 to 2012--Passenger Cars and LTVs--With Reviews of 26 FMVSS and the Effectiveness of Their Associated Safety Technologies in Reducing Fatalities, Injuries, and Crashes. DOT HS 812 069.
FOOTNOTE 9 Mark Freedman et al. 2009. Effectiveness and Acceptance of Enhanced Seat Belt Reminder Systems: Characteristics of Optimal Reminder Systems, Final Report. DOT HS 811 097.
FOOTNOTE 10 Charles J. Kahane. 2017. Fatality Reduction by Seat Belts in the Center Rear Seat and Comparison of Occupants' Relative Fatality Risk at Various Seating Positions. DOT HS 812 369.
Although seat belt use has steadily increased over the past few decades, usage rates for rear belts have consistently fallen below those for the front seats. According to data from
FOOTNOTE 11 Li, R., Pickrell, T.M. (2019, February). Occupant restraint use in 2017: Results from the NOPUS controlled intersection study (Report No. DOT HS 812 594).
FOOTNOTE 12 Li, R., Pickrell, T.M. (2019, February). Occupant restraint use in 2017: Results from the NOPUS controlled intersection study (Report No. DOT HS 812 594).
See illustration in Original Document.
NHTSA has, over time, used a variety of strategies to increase seat belt use, including sponsoring national media campaigns, providing assistance to states enacting seat belt use laws and high-visibility enforcement campaigns, and facilitating or requiring vehicle-based strategies. Some of these strategies are non-regulatory; some are regulatory. NHTSA has implemented a variety of non-regulatory approaches to increase seat belt use, such as the annual Click It or Ticket mobilization, which includes a national advertising campaign backed up by high-visibility local enforcement of state seat belt laws. Some states with mandatory rear seat belt laws include rear-seat specific messaging in their media campaigns.
One type of vehicle-based strategy is seat belt warning systems. Seat belt warning systems encourage seat belt use by reminding unbuckled occupants to fasten their belts and/or by informing the driver that an occupant is unbelted, so that the driver can request the unbelted occupant to fasten their seat belt. /13/ The warnings provided by seat belt warning systems typically consist of visual and/or audible signals. An optimized warning system balances effectiveness and annoyance, so that the warning is noticeable enough that the occupants will be motivated to fasten their belts, but not so intrusive that an occupant will circumvent or disable it or the public will not accept it. /14/ FMVSS No. 208 requires a seat belt warning system for the driver's seat, but not other seating positions. Most currently-produced vehicles also have a seat belt warning for the front outboard passenger seat, although FMVSS No. 208 does not require this.
FOOTNOTE 13 Akamatsu, M., Hashimoto, H., and Shimaoka, S., "Assessment Method of Effectiveness of Passenger Seat Belt Reminder," SAE Technical Paper 2012-01-0050, 2012, doi:10.4271/2012-01-0050. END FOOTNOTE
FOOTNOTE 14 See, e.g., Transportation Research Board Study, p. 25; DOT 2009 Belt Warning Study, p. 2. END FOOTNOTE
Based on the agency's New Car Assessment Program (NCAP) Buying a Safer Car data, about 13 percent of model year (MY) 2019 vehicles sold in
Euro NCAP introduced SBRS bonus points in 2002. The Euro NCAP protocol for Safety Assist systems describes which features a seat belt reminder must have to qualify for extra points. /15/ For rear seats, a visual signal must start once the ignition switch is engaged. The visual signal must be at least 60 seconds long. For systems without occupant detection, the visual signal must clearly indicate to the driver which seat belts are in use and not in use. For systems with occupant detection on all rear seating positions, the visual signal does not need to indicate the number of seat belts in use or not in use, but the signal must remain active if a seat belt remains unfastened on any of the occupied seats in the rear. No visual signal is required if all the rear occupants are belted. For systems with rear seat occupant detection, a 30-second audible signal needs to activate before reaching a vehicle speed of 25 km/h or before traveling 500 meters when any occupied seat has an unbuckled belt. Except for change of status events, the system may allow the driver to acknowledge the signal for rear seats and switch it off. /16/ Furthermore, when any seat belt experiences a change of status at vehicle speeds above 25 km/h, an audiovisual signal is required; the requirements for this warning are the same as for the seat belt reminder.
FOOTNOTE 15 European New Car Assessment Programme Assessment Protocol--Safety Assist, Version 8.0.2,
FOOTNOTE 16 For front seat belts, the assessment protocol requires both a visual and an audible warning signal. The front occupant visual signal must remain active until the seat belt is fastened. The audible signal for the front occupants has two stages, an initial and final audible signal, which have different onset criteria. The initial audible signal must not exceed 30 seconds and the final audible signal must be at least 90 seconds. To prevent unnecessary signals, the system must also be capable of detecting whether the front passenger seat is occupied. END FOOTNOTE
FOOTNOTE 17 ECE Regulation No. 16, Revision 9. END FOOTNOTE
FOOTNOTE 18 The regulation will be introduced in two phases:
III. Regulatory and Legislative History
Current Driver's Seat Belt Warning Requirements
FMVSS No. 208 is intended to reduce the likelihood of occupant deaths and the likelihood and severity of occupant injuries in crashes. The standard took effect in 1968 and from its inception required seat belts in passenger cars. /19/
FOOTNOTE 19 32 FR 2408, 2415 (
The standard currently requires a seat belt warning for the driver's seat belt on passenger cars; /20/ trucks and multipurpose passenger vehicles (MPVs) with a gross vehicle weight rating (GVWR) of 4,536 kilograms (kg) (10,000 pounds (lb)) or less (except for some compliance options which do not require the warning); /21/ and buses with a GVWR of 3,855 kg (8,500 lb) or less and an unloaded weight less than or equal to 2,495 kg (5,500 lb). /22/ The regulations do not require seat belt warnings for any seating position other than the driver's seat. /23/
FOOTNOTE 20 S22.214.171.124(a)(3); S7.3. END FOOTNOTE
FOOTNOTE 21 S4.2.6; S7.3. END FOOTNOTE
FOOTNOTE 22 S4.2.6 (with the exception of some options). END FOOTNOTE
FOOTNOTE 23 See, e.g., Interpretation Letter from NHTSA to
Manufacturers have two compliance options for the driver's warning. /24/ The first option requires that if the key is in the "on" or "start" position and the seat belt is not in use, the vehicle must provide a visual warning for at least 60 seconds, and an audible warning that lasts 4 to 8 seconds. Under the second option, when the key is turned to the "on" or "start" position, the vehicle must provide a visual warning for 4 to 8 seconds (regardless of whether the driver seat belt is fastened) and an audible warning lasting 4 to 8 seconds, if the driver seat belt is not in use. What is now the second option (S7.3(a)(2)) became effective in 1974 and has remained unchanged since then. /25/ What is now the first option (S7.3(a)(1)) was added to S7.3 in 1991. /26/
FOOTNOTE 24 49 CFR 571.208, S7.3. END FOOTNOTE
FOOTNOTE 25 See 39 FR 42692 (
FOOTNOTE 26 See 56 FR 3222 (
NHTSA Experience in the 1970s: Consumer Backlash Against Seat Belt Interlock and Subsequent Statutory Limitation on Belt Warning Requirements
Prior to 1974, NHTSA had promulgated a series of occupant protection regulations that, at various times, specified as compliance options various combinations of active and passive occupant crash protection, seat belt interlocks, and seat belt warnings. /27/ A seat belt warning was first required in 1971, when NHTSA sought to increase seat belt use by adopting occupant protection compliance options that included the use of a seat belt warning for the front outboard seating positions. /28/ This seat belt warning option required audible and visible warning signals that lasted for as long as the occupant was unbelted, the ignition was "on," and the transmission was in forward or reverse. In 1972, NHTSA adopted occupant protection options for passenger cars that included (for cars that did not provide automatic protection) an interlock system that would prevent the engine from starting if any of the front seat belts were not fastened. /29/ Contrary to the agency's expectations, the initial vehicle introduction of these systems in the early 1970s was not well-received by the public. In particular, continuous buzzers and ignition interlocks annoyed many consumers to the point of their disabling or circumventing the systems.
FOOTNOTE 27 "Active protection" refers to features, such as manual seat belts, that require action by the occupant, while "passive protection," sometimes called "automatic protection," refers to safety features that do not require any action by the occupant other than sitting in a designated seating position. Seat belt interlocks prevent starting or operating a motor vehicle if an occupant is not using a seat belt. For a fuller discussion of the history of the active and passive protection requirements in FMVSS No. 208, see
FOOTNOTE 28 36 FR 4600 (
FOOTNOTE 29 37 FR 3911 (
As a result of the strong negative consumer reaction,
FOOTNOTE 30 These amendments were codified at 49 U.S.C. 30124. As explained below, this provision was amended in 2012 by MAP-21. END FOOTNOTE
FOOTNOTE 31 39 FR 42692 (
Recent Regulatory History
In 2001, the
FOOTNOTE 32 House Report 107-108,
FOOTNOTE 33 Transportation Research Board Study, p. 9. END FOOTNOTE
In 2002 and 2003, NHTSA sent letters to several vehicle manufacturers encouraging them to enhance seat belt warning systems beyond the FMVSS No. 208 minimum requirements. /34/ (An "enhanced" warning system is one with visual and/or audible warning signals that exceed the maximum durations specified in S7.3, and/or that applies to seating positions other than the driver's seat). The agency also determined that the Safety Act did not prohibit manufacturers from implementing enhanced warning systems as long as the manufacturer provided some means of differentiating the voluntarily-provided signal from the required signal (for example, by a clearly distinguished lapse in time between the two signals). /35/ Many vehicle manufacturers subsequently implemented enhanced seat belt warnings for the driver and front outboard passenger seating positions. Based on information submitted to the agency in connection with the agency's NCAP for MY 2018, 99.9 percent of participating vehicle models offered for sale in the
FOOTNOTE 34 See
FOOTNOTE 35 See
FOOTNOTE 36 IIHS reported that enhanced SBRSs are standard equipment for the driver and front passenger in 90 and 78 percent, respectively, of the 2013 vehicle models. This is based on the data maintained in their
FOOTNOTE 37 Public Law 109-59,10306 (2005). END FOOTNOTE
FOOTNOTE 38 Docket No. NHTSA-2010-0061-0002. END FOOTNOTE
FOOTNOTE 39 75 FR 37343 (
FOOTNOTE 40 Moving Ahead for Progress in the 21st Century Act (MAP-21), Public Law 112-141 (2012). END FOOTNOTE
FOOTNOTE 41 Id. at
FOOTNOTE 42 Id. at
FOOTNOTE 43 Section 30111 requires that a Motor Vehicle Safety Standard meet the need for safety, be stated in objective terms, and be practicable, among other requirements. See infra, Part V. END FOOTNOTE
FOOTNOTE 44 78 FR 5865 (
In light of the Congressional directives concerning seat belt warnings, NHTSA has taken a variety of actions to research the effectiveness and acceptance of seat belt warnings.
In 2002, the agency chartered an integrated project team to recomm8end strategies for increasing seat belt use. /45/ The team's report, issued in 2003, observed that "[d]espite the significant increases over the past twenty years, safety belt use in
FOOTNOTE 45 See 68 FR 46262 (
In response to the 2005 SAFETEA-LU mandate, NHTSA undertook a multi-phase research study of seat belt warnings. NHTSA published several reports. Three are particularly relevant to today's ANPRM. The first is a large-sample national observational study on the effectiveness of front seat belt warnings. /47/ The study covered several states in different parts of the country. The vehicles in the study sample had a wide variety of seat belt warning systems. These included warning systems that had only the minimum features required by FMVSS No. 208, as well as twenty different enhanced warning systems. Because of the detail of the data gathered (e.g., occupant demographic and vehicle-specific information), the analysis was able to control for confounding factors. The second study used an experimental or focus-group-based approach to study consumer acceptance as well as effectiveness. /48/ The third report summarized and extended the analyses from the previous two reports. /49/ This series of research studies showed, among other things, that the presence of an enhanced front seat belt reminder system increased front outboard passenger seat belt use by about 3 to 4 percentage points more than in vehicles with only a driver seat belt warning system meeting the minimum requirements in S7.3.
FOOTNOTE 47 Mark Freedman et al. The Effectiveness of Enhanced Seat Belt Reminder Systems Draft Report: Observational Field Data Collection Methodology and Findings. 2007. DOT HS-810-844.
FOOTNOTE 48 N. Lerner et al. 2007. Acceptability and Potential Effectiveness of Enhanced Seat Belt Reminder System Features. DOT HS 810 848.
FOOTNOTE 49 DOT 2009 Belt Warning Study, supra. END FOOTNOTE
NHTSA continued and expanded on this work several years later. In 2015 the agency completed an additional report on the effectiveness and consumer acceptance of rear seat belt warnings, based on a consumer survey. /50/ This study utilized a telephone survey of the drivers of vehicles with and without rear seat belt warning systems. The study found that overall, drivers of vehicles with a rear seat belt warning system were satisfied with the system and noticed an increase in rear seat belt use. For example, among drivers of vehicles with a rear seat belt warning, approximately 80 percent were satisfied with the system and 65 percent reported that the rear seat belt warning made it easier to encourage rear seat passengers to buckle up.
FOOTNOTE 50 Paul Schroeder &
The results of NHTSA's research are discussed in more detail in Section VI.A and VI.C-D. The relevant research reports have also been placed in the docket for this rulemaking.
FOOTNOTE 51 49 U.S.C. 30111(a). END FOOTNOTE
FOOTNOTE 52 49 U.S.C. 30102(a)(8). END FOOTNOTE
FOOTNOTE 53 30102(a)(9). END FOOTNOTE
FOOTNOTE 54 30111(b)(1). END FOOTNOTE
FOOTNOTE 55 30111(b)(3)-(4). END FOOTNOTE
FOOTNOTE 56 See 49 CFR part 1.95. END FOOTNOTE
MAP-21 requires the Secretary to initiate a rulemaking proceeding to amend FMVSS No. 208 to provide a safety belt use warning system for designated seating positions in the rear seat. /57/ It directs the Secretary to either issue a final rule, or, if the Secretary determines that such an amendment does not meet the requirements and considerations of 49 U.S.C. 30111, to submit a report to
FOOTNOTE 57 Moving Ahead for Progress in the 21st Century Act (MAP-21), Public Law 112-141, 31503 (2012). END FOOTNOTE
VI. Issues on Which NHTSA Seeks Information From the Public
As it continues with the proceeding required to be initiated by MAP-21, NHTSA seeks comment on a variety of issues related to amending FMVSS No. 208 to require a rear seat belt warning system. These include: The types of seat belt warning system requirements the agency should propose; the effectiveness of such systems at increasing rear seat belt use; the degree to which consumers would accept such systems; the associated benefits and costs; and the vehicles to which any proposed requirements should apply.
A. Potential Specifications for a Required Rear Belt Warning System
NHTSA is considering proposing any of a variety of minimum requirements for a rear seat belt warning system. There are a variety of aspects of the possible proposed requirements that we seek comment on. NHTSA especially seeks any data related to these issues.
1. Should the warning be visual-only, audible-only, or audio-visual? If NHTSA were to propose requirements for a warning that is similar to existing seat belt warnings, should the warning be visual-only (e.g., a telltale displaying text or icons), audio-only, or audio-visual? (Below we also seek comment on alternative non-traditional approaches.) FMVSS No. 208 requires the driver's seat belt warning to be audio-visual. Seat belt warnings for front outboard passenger seats (which are not required by FMVSS No. 208) currently on the market are also typically audio-visual. NHTSA's research suggests that audible warnings in conjunction with visual warnings are generally more effective than text or icons alone, but are also more intrusive. /58/ However, research has not yet firmly established which system characteristics are optimal. /59/ Neither Euro NCAP or the ECE regulation require an audible warning for rear seats.
FOOTNOTE 58 DOT 2009 Belt Warning Study, supra, p. 39 (drivers); p. 45 (passengers). END FOOTNOTE
FOOTNOTE 59 DOT 2009 Belt Warning Study, p. 1. END FOOTNOTE
. Below we ask specific questions about potential specifications for visual and audible warnings, and, more generally, which of these NHTSA should propose for the rear seat belt warning system minimum requirements. Should whether the warning is visual or audible depend on when the warning is given and what it is for (e.g., a visual warning at the beginning of the trip and an audible warning during the trip if a buckled belt becomes unfastened)? Should it also depend on the recipient of the warning (for example, driver versus rear passenger)?
NHTSA also seeks comment on whether an audible warning alone, without a visual warning, would be an effective way to alert the driver to the status of the rear seat belts and increase rear seat belt use. For example, would an audible notification (e.g., a chime) indicating that a rear-seat occupant had buckled the belt effectively inform the driver (or facilitate the driver in determining) whether there were any unbuckled rear-seat occupants? We also seek comment on the costs and benefits of different types of warnings.
2. Triggering conditions. Since seat belt warning systems are generally initiated at the beginning of a trip (i.e., when the ignition switch is moved to the "on" or "start" position) so as to assure that occupants are safely restrained prior to any potential vehicle crash, this is perhaps the most intuitive approach for rear seat belt warnings as well. However, might it be preferable to delay the warning to a time when the warning could be given greater attention and, perhaps, the driver (or other occupant) is less distracted? Would delaying the warning until the vehicle is placed in gear make it more likely that the occupants fasten their belts before the vehicle is in motion? Are there other triggering conditions for the start of a trip NHTSA should consider, and what would be the justification for choosing them? Would the triggering condition necessitate occupant detection? Should the warning be required/allowed/disallowed if the/a belt is buckled?
In addition to a warning at the beginning of a trip, should there be a warning if a seat belt becomes unbuckled in the course of a trip (a change-of-status warning)? Such a warning may reduce the risk of injury to children by alerting the driver that a child has unbuckled his or her seat belt, providing the driver an opportunity to direct the child to re-buckle the belt. The signal may also potentially prevent children from unbuckling their seat belts. The agency's 2015 Survey of Principal Drivers of Vehicles with a Rear Seat Belt Reminder System found that a change of status warning is effective in getting passengers to refasten their seat belt. /60/ Volvo and Jaguar Land Rover vehicles sold in
FOOTNOTE 60 Paul Schroeder &
FOOTNOTE 61 ECE Regulation No. 16, Revision 9
If NHTSA should propose a change-of-status warning, what should the triggering condition(s) be? Should it be linked to the vehicle's speed and/or transmission position (e.g., forward or reverse, or other criteria), and if so, what should the criteria be, and why? Similarly, should there be criteria for the duration of the warning? In order to earn bonus points, Euro NCAP requires the system to activate the change of status warning immediately at vehicle speeds over 25 km/h. If the change of status occurs below 25 km/h and no doors are opened, the signal may be delayed until the vehicle has been in motion for 500 meters. /62/ The ECE regulation uses similar thresholds, but lets the manufacturer choose either a speed, distance traveled, or a duration threshold. /63/ Are there situations when the warning at a low speed would result in an unnecessary or unwanted warning, and how frequently would such situations occur?
FOOTNOTE 62 European New Car Assessment Programme Assessment Protocol--Safety Assist,
FOOTNOTE 63 ECE Regulation No. 16, Revision 9
3. Alternative warning systems. NHTSA also seeks comment on whether it should require or specify as a compliance option a rear seat belt warning that differs from the type of audio-visual warning that is currently required for the driver's seat belt. Alternatives to a visual warning (telltale) on vehicle start-up could include an audible signal, either electronic or mechanical, or a haptic warning (e.g., steering wheel or seat vibration). Similarly, an audible or visual warning of a change in the status of rear seat belts could be either electronic or mechanical and could include a haptic signal. For example, to what extent does the sound of the latch plate clicking into the buckle when a belt is fastened currently serve as an indication of seat belt use? Would that sound, perhaps augmented, serve as an effective notice to the driver that a rear-seat occupant had buckled the belt, or the lack of such sound indicate that a rear-seat occupant had not buckled the belt? To facilitate an effective warning that advances safety and is appropriate for diverse vehicle types and uses, NHTSA seeks comment on alternative cost-effective solutions that would alert the driver when a rear seat passenger buckles and/or unbuckles. For any alternative warning systems/signals that are identified, NHTSA seeks information on the issues we identify below. For example, how would such an alert function if there were multiple rear-seat occupants? Would the warning be distinguishable from other alerts that are provided to the driver? How would the costs and benefits of such a warning compare to more traditional types of warnings?
4. Occupant detection technology. NHTSA also seeks comment on warning systems that utilize occupant detection.
Rear seat warning systems that employ occupant detection have potential advantages over systems that do not utilize it. With occupant detection, a warning system can provide more informative warnings. The system can determine whether any seats are occupied by an unbelted occupant, as opposed to simply notifying the driver which or how many belts, if any, are fastened. Such systems are also better able to appropriately target audible warnings or longer-duration visual warnings (enhanced warnings). Having an audible or longer-duration visual warning activate for an unoccupied seat (such as might be the case if the system did not have occupant detection) could be a nuisance for the driver and might either desensitize the occupants to the warning signal, or lead them to circumvent or defeat the system.
However, occupant detection for the rear seats may present both technical and cost challenges. /64/ Rear seats are used in ways that complicate occupant detection. Rear seats may frequently be used to transport cargo such as groceries, pets, and other heavy objects, which could be mistaken for an occupant. Rear seats are frequently used for child restraint systems attached by a child restraint anchorage system, or LATCH. /65/ An occupant detection system in the rear seat may have difficulty detecting a child restraint system. In addition, rear seats may be less well-defined than most front seats, which could make it more challenging for a sensor to define seat occupancy accurately. For example, it may be technically challenging for an occupant detection system to recognize a large occupant spanning multiple seating positions as a single occupant rather than two occupants. These challenges may be greater or lesser depending on the rear seat configuration of the vehicle. A seat belt warning system utilizing occupant detection technology could provide false reminders if the occupant detection were inaccurate. A problem with false reminders is that they can lead occupants to disregard or attempt to circumvent the system, defeating the purpose of such systems. Occupant detection is also likely to add cost to a rear sear warning system. Euro NCAP does not specify that occupant detection for rear seats is needed in order to obtain bonus points. /66/ The ECE regulations do not require occupant detection.
FOOTNOTE 64 In the
FOOTNOTE 65 Many in the child passenger safety community refer to the child restraint anchorage system as the "LATCH" system, an abbreviation of the phrase "
FOOTNOTE 66 European New Car Assessment Programme Assessment Protocol--Safety Assist,
We seek comment on whether NHTSA should propose warning system requirements that would necessitate occupant detection for the rear seats, and the technical and cost feasibility of doing so.
NHTSA also seeks comment on proposing multiple compliance options for the warning system requirements. Should all the compliance options require occupant detection, or should there be some compliance options that do not require occupant detection? To what extent should we expect increased effectiveness and benefits for a system utilizing occupant detection compared to a system without such technology? What would be the increased cost associated with such a system (on a per seat and per vehicle basis), and how would it compare to the increased benefits (if any)?
5. Enhanced warning systems. Enhanced warning systems utilize warnings that are relatively longer-lasting or have an audible component beyond the minimum FMVSS No. 208 requirements for the driver's seat warning. Research by NHTSA and others suggests that audible warnings in conjunction with visible warnings are potentially more effective than visible warnings alone. /67/ As noted above, an enhanced warning that activates for an unoccupied seat could be a nuisance that either desensitizes the occupants to the warning signal or leads them to circumvent or defeat the warning. Enhanced warnings therefore generally need to work in conjunction with an occupant detection system, and even this might not completely eliminate the possibilities of false warnings (for example, if a rear seat is occupied by a pet or groceries).
FOOTNOTE 67 See, e.g., DOT 2009 Belt Warning Study, supra, pp. 54, 57. See also
In addition to this, while enhanced warnings are potentially more effective due to their persistence and annoyance, /68/ they also present potential consumer acceptance challenges for the same reasons. Considering the history in this area as described above, the agency is particularly concerned with striking the right balance. NHTSA's research suggests that there is an inherent trade-off between effectiveness and acceptability. /69/ The agency's research has noted that no clear consensus exists about which warning system features are most acceptable, /70/ and that the data regarding acceptance so far are "limited, subjective, and anecdotal." /71/ It has also been pointed out that the research on seat belt use and acceptability among drivers may not be representative of situations where multiple passengers are present and that further evaluation is warranted on the annoyance and acceptance of seat belt warnings. /
FOOTNOTE 68 See, e.g., DOT 2009 Belt Warning Study, supra, p. 54. END FOOTNOTE
FOOTNOTE 69 See id. p. 60. END FOOTNOTE
FOOTNOTE 70 DOT 2009 Belt Warning Study, supra, p. 8; Schroeder & Wilbur, supra, p. 33. END FOOTNOTE
FOOTNOTE 71 DOT 2007 Acceptability Study, supra, p. 41. END FOOTNOTE
FOOTNOTE 72 DOT 2007 Acceptability Study, supra, pp. 41-42. END FOOTNOTE
FOOTNOTE 73 ECE Regulation No. 16, Revision 9
6. Belt use criteria. The current driver's belt warning requirements specify that a belt is "not in use" when, at the option of the manufacturer, either the seat belt latch mechanism is not fastened or the belt is not extended at least 10.16 centimeters (cm) (4 inches (in)) from its stowed position. /74/ Should NHTSA retain these criteria to determine if a rear seated occupant is belted, and if not, what should the criteria be, and why?
FOOTNOTE 74 S7.3(c). END FOOTNOTE
7. Seat occupancy criteria. If NHTSA were to propose system requirements for occupant detection (either mandatory or as a compliance option), seat occupancy criteria might be necessary to objectively specify when a seat is occupied for the purposes of NHTSA's compliance testing. Because the existing seat belt warning requirements in S7.3 apply only to the driver seat, they do not contemplate an occupant detection system (because, traditionally, driver seat occupancy could be assumed).
Accordingly, NHTSA might need to propose seat occupancy criteria. If so, what should the criteria be? First, what type of occupants should the criteria be based on; e.g., should they be based on a mid-size male, small-size female, or a child? Should the system be required to register small children that would presumably be placed in a child restraint system? Should the criteria take into account the presence of child restraint systems?
Next, for the type(s) of occupants upon which the criteria are based, what should the criteria be? Should NHTSA consider the same seat occupancy criteria specified in FMVSS No. 208 for compliance testing of low-risk deployment and suppression air bag systems? To test whether an air bag system either suppresses or properly deploys the front outboard passenger air bag in the presence of a child or small-stature individual, NHTSA tests the air bag system with a variety of different dummies. For example, for the static suppression and low-risk deployment compliance options, FMVSS No. 208 specifies multiple performance tests using 1-, 3-, and 6-year-old Anthropomorphic Test Devices (test dummies) both in and out of a Child Restraint System (CRS). In addition, in order to ensure that the suppression feature does not inappropriately suppress the air bag for small-statured adults, FMVSS No. 208 requires the air bag system to be active during several static tests using a 5th percentile adult female dummy in the right front passenger seat.
In order to perform compliance testing on a rear seat belt warning system that uses occupant detection, should NHTSA use one or more of these dummies, or specify occupancy conditions based on one of these dummies? For example, NHTSA could specify use of the 6-year-old test dummy. Alternatively (or in addition), NHTSA could specify that a rear seat would be considered "occupied" when an occupant who weighs at least 21 kg (46.5 lb), and is at least 114 cm (45 in) tall is seated there. These measurements come from FMVSS No. 208, S29.1(e), and correspond to the height and weight requirements for a child who is used as an alternative for the 6-year-old child test dummy for compliance testing of advanced air bag systems utilizing static suppression. Is this an appropriate threshold? NHTSA also seeks comment on the potential for false warnings, and how this might be addressed.
8. Making the system resistant to intentional and inadvertent defeat. As part of the agency's seat belt interlock research program, we recently performed research on the development of a seat belt misuse detection system, /75/ so we are aware there are a number of ways in which a rear seat belt warning system might be intentionally defeated, as well as potential countermeasures. For example, a warning system could be defeated if:
FOOTNOTE 75 Mazzae, E.N., Baldwin, G.H.S., & Andrella, A.T. (2018, October). Performance assessment of prototype seat belt misuse detection system (Report No. DOT HS 812 593).
* The belt was buckled before the occupant sat in the seat. This could be addressed by requiring a sequential logic system. A sequential logic system would require that the belt be buckled after the seat has been occupied in order for the system to recognize the seat belt as being buckled;
* An occupant buckles the seat belt behind themselves. This could be addressed by utilizing seat belt buckle and spool-out sensors and deactivating the warning only if the webbing were spooled out more than a predetermined length. However, even these sensors could be defeated by pulling out additional webbing and clipping it off to prevent retraction; or
* The seat belt and/or occupant detection sensors utilized by the rear warning system in vehicles with removable rear seats are intentionally disconnected.
There are also scenarios involving inadvertent circumvention that could impact the effectiveness and accuracy of a rear belt warning system. One scenario is when the driver uses a remote engine starter so that the initial warning activates before the driver (and perhaps the rear seat occupants) are in the vehicle. This might be addressed by programming the system to require input from door or occupant sensors to verify that the driver is in the vehicle. There are, of course, a variety of other ways the warning system might be intentionally or inadvertently circumvented.
We seek comment on whether NHTSA should propose requirements to address circumvention. We also seek comment on whether we should propose requiring a single-trip manual deactivation of the seat belt warning system once the minimal signal performance requirements are met, which might diminish the likelihood of circumvention. /76/ The ECE regulations allow the rear seat belt warning system to incorporate a short-term and/or a long-term deactivation feature for the audible change-of-status warning. /77/ Under these regulations, a short-term deactivation may only be effectuated by specific controls that are not integrated in the safety-belt buckle and only when the vehicle is stationary. /78/ When the ignition or master control switch is deactivated for more than 30 minutes and activated again, a short-term deactivated safety-belt reminder must reactivate. A long-term deactivation may only be effectuated by a sequence of operations that are detailed only in the manufacturer's technical manual or which require tools that are not provided with the vehicle. /79/ To what extent would a deactivation feature reduce the effectiveness of the warning? Would a deactivation feature only be needed for systems with a persistent audible warning?
FOOTNOTE 76 A single-trip manual activation refers to a feature that allows the driver to acknowledge a visual or audio signal--e.g., with a press of a button--and not continue seeing or hearing it. END FOOTNOTE
9. Electrical Connection Requirements. A rear seat belt warning system might require an electrical connection between the seat and the vehicle to relay the information gathered by a buckle or webbing spool-out sensor to the rest of the warning system. A rear-belt warning system may therefore present potential wiring complexities, particularly in vehicles with removable, folding, rotating, or stowable seats. These types of seats might present an issue for a rear seat belt warning system because the electrical connection might not be reestablished for these seats when the seat is reinstalled. There could be instances for manual connection seats where the driver either forgets to make the connection or makes an improper connection. Even for seats where the connections are automatically established when the seat is reinstalled, the automatic connectors might malfunction and a proper connection may not be made. If the electrical connection is not reestablished, the warning system could malfunction or provide inaccurate information. This issue might predominantly affect minivans, which make up a small percentage of the fleet. Removable seats are mainly found in the second row of minivans. Foldable, rotating or otherwise stowable seats (e.g., Stow-n-Go, Flip and Fold) are prominent in the third row of minivans or large sport utility vehicles. Foldable or stowable seats in the second row are not as prominent in minivans.
A variety of potential system requirements could be proposed to address this potential issue. The warning system in such vehicles might be required to automatically connect the electrical connections when the seat is put in place or, if a manual electrical connection is required, the connectors might be required to be readily accessible. The system could also provide a warning signal to inform the driver if a proper electrical connection has not been made with respect to an easily removable seat. Euro NCAP and the revised ECE regulations do not have such specifications. The ECE regulations provide that the rear seat belt warning requirements will not apply to removable rear seats or to seats in a row in which there is a suspension seat until
NHTSA seeks comment on this issue, particularly on whether such electrical connection requirements should be proposed, and if so what they should be, and what types of seats they should be required for. Are there new and innovative wireless technologies that could reduce or eliminate wiring complexities, such as those used in tire pressure monitoring systems? The agency also seeks comment on the safety need for such warnings and the costs and feasibility of addressing these issues.
10. Owner's manual/label requirements. We also seek comment on whether NHTSA should propose that information be provided in the vehicle owner's manual that accurately describes the warning system's features, including the location and format of the visual warnings, in an easily understandable format. Information of this sort is already required by FMVSS No. 208 for the driver's seat belt warning. Owner's manual readership may be relatively low, /80/ so we also seek comment on whether we should require that this information be displayed in the vehicle instead of (or in addition to) the owner's manual. Should information about the reconnection of electrical components for any removable/stowable seats be placed in close proximity to the seat's electrical connection?
FOOTNOTE 80 The National Child Restraint Use Special Study found that only 13 percent of drivers reported reading the vehicle owner's manual.
11. Interaction with other vehicle warnings. NHTSA also seeks comment on whether a rear seat belt warning could conflict with other in-vehicle warnings. We seek comment on how NHTSA might specify warning requirements so that any such conflicts are avoided or minimized, and, if a conflict cannot be avoided, which warning, if any, should take precedence.
12. Harmonization with regulatory requirements or new car assessment programs in other markets. NHTSA also seeks comment on whether and to what extent any proposed requirements might (or should) be based upon or differ from other regulatory requirements (such as ECE requirements) or consumer information programs (such as Euro NCAP).
With respect to potential requirements for a visual rear seat belt warning, NHTSA seeks comment on the following:
13. Visual warning location. Who should the signal warn--the driver, the rear passenger(s), or both? A seat belt warning can function either by alerting the driver that a rear seat belt is unbuckled, leaving it to the driver to request the rear passenger to buckle up; it can warn the rear passenger(s) directly that their belt is unbuckled; or it can warn both the driver and rear passenger(s). Some research may suggest that having the warning visible to the unbelted occupant may increase effectiveness. /81/ The new ECE regulation simply requires that the visual warning be visible to the driver when they are facing forward. /82/ NHTSA seeks comment on whether the warning should be visible to the driver, the rear passenger(s), or both. To what extent would requiring a warning be visible to rear passengers increase cost and complexity, and would this be justified? Where should the visual warning be located, especially with respect to the rear passenger, if such a telltale were appropriate? To what extent would or should such requirements constrain manufacturers' design choices, and how could such constraints be minimized?
FOOTNOTE 81 DOT 2007 Acceptability Study, supra, pp. 67-68. END FOOTNOTE
FOOTNOTE 82 ECE Regulation No. 16, Revision 9
14. What type of information should the warning convey? Particularly with respect to a visual warning for the driver, what type of information should a visual warning convey? For example, the system could indicate how many or which rear seat belts are in use (a "positive-only" system); how many or which rear seat belts are not in use (a "negative-only" system); or how many or which rear seat belts are in use and how many or which rear seat belts are not in use (a "full-status" system).
Each of these systems could have strengths and limitations. A positive-only system would be the least technically complex of the three. Since it would only need to detect whether a seat belt is in use, it would require seat belt latch or webbing spool-out sensors (assuming no defeat sensing was required). With a positive-only system, the driver would need to determine how many rear seat occupants there are and then determine if that number equals the number of seat belts that are reported by the warning system as buckled. This compliance option would not necessitate occupant detection.
Negative-only and full-status systems would provide more direct information to the driver, but might be more technically complex. These systems might be more effective than a positive-only system because they would directly inform the driver whether any rear seat occupants were unbuckled, without the driver having to compare the number or location of occupants and fastened belts. In addition, as discussed above, warning systems equipped with occupant detection are more amenable to audible warnings and enhanced warning features. However, such systems might require occupant detection sensors in order to minimize or eliminate false warnings. (Because the negative-only and full-status systems would indicate the presence of an unbuckled belt, they would probably want to avoid giving this warning unless the seat were occupied; if not, such "false positives" could lead the driver the disregard the warning or circumvent the system.)
NHTSA seeks comment on the relative merits of such systems. Should NHTSA propose one or more of these systems as requirements or compliance options? How much more effective would the more informative negative-only and full-status systems be? How much more complex or expensive would they be? Would occupant detection be necessary for these systems? NHTSA also seeks comment on whether there are alternative warning systems that would convey alternative or additional information to the driver (or rear passengers). For example, would a less sophisticated warning, such as a specialized system of mirrors, be sufficient to inform the driver about the status of the rear seat belts?
15. Telltale Characteristics. If a visual warning system including a telltale were to be required, should NHTSA propose requirements for telltale characteristics, and if so, what should they be? Should the warning be standardized, and would this increase the likelihood that consumers would notice, recognize, and respond to the warnings? For example, should NTHSA propose requirements for the color of the telltale, required text, pictorial vs. alphanumeric, or whether it flashes?
16. Minimum duration. What should the minimum duration of a visual warning be? The current driver's seat belt visual warning is required to last at least 60 seconds under the second compliance option. What minimum length of time would be sufficient to capture the driver's (or passenger's) attention for the rear seat belt warning, without becoming a distraction or nuisance for the driver (or passenger)? NHTSA's research (for front seat belt warnings) suggests that longer-duration warnings are more effective, but also more annoying. /
FOOTNOTE 83 DOT 2009 Belt Warning Study, supra, p. 57. END FOOTNOTE
With respect to audible warnings, we seek comment on the following:
17. Minimum duration. If an audible warning requirement were adopted for the change-of-status warning, what should the minimum duration of an audible warning be? Because MAP-21 removed the 8-second limitation, NHTSA may require longer-lasting audible warnings. NHTSA is, however, cognizant of the fact that longer warnings lead to annoyance. What duration would appropriately balance effectiveness and annoyance? Euro NCAP specifies that a change-of-status audible warning must be 30 seconds long in order to receive bonus points. /84/ The new ECE regulation also specifies that a change-of-status audible warning component be 30 seconds long. /85/
FOOTNOTE 84 European New Car Assessment Programme Assessment Protocol--Safety Assist,
FOOTNOTE 85 ECE Regulation No. 16, Revision 9
18. Other audible signal characteristics. If it mandates an audible warning, should NHTSA specify any additional audible warning characteristics (for example, a minimum/maximum sound level)?
19. NHTSA seeks comment on the vehicles to which any proposed rear seat belt warning requirements should apply. We also seek comment on whether any vehicles within the broad applicability criteria should be exempt. Rear seat belts are generally required except in certain buses (such as school buses) between 10,000 lb and 26,000 lb, and for school, perimeter, and transit buses over 26,000 lb. (Other exceptions also apply.) We especially seek comment on whether a rear seat belt warning should be required for high-occupancy vehicles such as 15-passenger vans, large sport utility vehicles, school buses, and large trucks and vans with a GVWR less than or equal to 4,536 kg (10,000 lb). /86/
FOOTNOTE 86 Fifteen-passenger vans are classified as "buses" because they are designed for carrying more than ten persons. See S571.3. END FOOTNOTE
Vehicles with a larger number of rear seats may present visual signal complexities and other challenges. At the same time, such vehicles could be at least as likely, if not more likely, to have rear occupants. With respect to school buses, we acknowledge that a rear seat belt warning requirement might place additional cost burdens on school systems, given that such cost can lead to reductions in school bus service, resulting in greater risk to students. /87/ We also note that school buses of all sizes offer passengers compartmentalization protection to reduce the risk of crash injury, even to the unbelted.
FOOTNOTE 87 See 76 FR 53102 (
We seek comment on what vehicle types should be included and excluded, including the costs and benefits of inclusion. We also seek comment on ways to propose performance requirements that provide manufacturers with the flexibility to design a warning system that is appropriate for each vehicle type.
20. NHTSA seeks comment on the effectiveness of rear seat belt warning systems. NHTSA's research suggests that at least some unbelted rear seat occupants might be amenable to wearing a seat belt. Seat belt non-users are typically categorized as either "part-time" non-users or so-called "hard-core" non-users. /88/ Part-time non-users are those non-users who generally express positive attitudes toward seat belts, but do not always buckle up, due to a range of reasons, such as short trips, forgetfulness, and being in a rush. /89/ Hard-core non-users are those who "generally do not acknowledge the benefits of seat belts and are opposed to their use." /90/ NHTSA's consumer research shows that part-time non-users make up the majority of non-users (83%), while hard-core non-users make up a smaller proportion of non-users (17%). /91/ According to the results of NHTSA's most recent self-reporting survey of seat belt use, the
FOOTNOTE 88 See, e.g., Transportation Research Board Study, supra, p. 3. END FOOTNOTE
FOOTNOTE 89 John M. Boyle &
FOOTNOTE 90 Transportation Research Board Study, supra, p. 40. END FOOTNOTE
FOOTNOTE 91 Calculated from Boyle & Lampkin, supra, p. 11 (Fig. 6). This considers respondents who reported that they "Never" or "Rarely" used a seat belt to be hard-core nonusers. See Transportation Research Board Study, supra, p. 31 n.3. This does not include respondents who indicated that they never drive. The number of non-drivers surveyed was relatively small. Boyle & Lampkin, supra, p. 75. END FOOTNOTE
FOOTNOTE 92 Boyle & Lampkin, supra, p. iv. This is a national telephone survey periodically conducted by NHTSA. Because, unlike NOPUS, it is not observational, the MVOSS is not the best indicator of national belt use. In addition, because of respondent bias, the large number of part time users, and the tendency for survey respondents to over-report belt use, MVOSS use rates have typically been about 10 percentage points higher than those from NOPUS. MVOSS does, however, provide demographic detail that cannot be observed and insight into the reasons people do and do not use seat belts. See
FOOTNOTE 93 Boyle & Lampkin, supra, p. 41. END FOOTNOTE
FOOTNOTE 94 Transportation Research Board Study, supra, pp. 39-40, 61; Boyle & Lampkin, supra, pp. 36, 38. END FOOTNOTE
A rear seat belt warning system can increase rear seat belt use in two ways: It can remind a rear seat occupant to fasten his or her belt, and it can inform the driver that a passenger is unbuckled, so that the driver can request the occupant to fasten their belt. Without a rear seat belt warning, the driver must turn around to ascertain whether a rear seat occupant is using a seat belt (or ask the occupant); in some vehicles, belt use may not be evident to the driver, even if he or she turned around, due to line-of-sight limitations. In NHTSA's 2015 Survey of Principal Drivers of Vehicles with a Rear Seat Belt Reminder System, 65 percent of drivers of vehicles equipped with rear seat belt reminders reported that the rear seat belt reminder made it easier to encourage the rear seat passengers to buckle up. /95/
FOOTNOTE 95 Paul Schroeder &
NHTSA has conducted a variety of research relating to the effectiveness of in-vehicle seat belt warnings. First, it conducted the multi-phase seat belt warning study that was part of the research program initiated pursuant to SAFETEA-LU. The analysis demonstrated that the presence of an enhanced front seat belt reminder system increased front outboard passenger seat belt use by about 3 to 4 percentage points more than in vehicles with only a driver seat belt warning system meeting the minimum requirements in S7.3. /96/
FOOTNOTE 96 DOT 2009 Belt Warning Study, supra, p. 21. END FOOTNOTE
Second, NHTSA's 2015 Survey of Principal Drivers of Vehicles with a Rear Seat Belt Reminder System studied the effectiveness and acceptability of rear seat belt warnings based on a consumer telephone survey of the drivers of vehicles with and without rear seat belt warning systems. /97/ The study found, among other things, that about one quarter of drivers (24%) of vehicles equipped with a rear seat belt warning system noticed an increase in rear seat belt use. When asked about their experience with the change of seat belt buckle status alert, close to half of drivers of vehicles with a rear seat belt warning system (49%) said that their system has indicated that a passenger had unfastened his/her seat belt within the past year. Overall, of those who reported experiencing a change of seat belt status alert (49%), over three-quarters of these drivers (77%) said that the unbuckled passenger eventually did refasten her seat belt, either on her own or at the driver's request.
FOOTNOTE 97 Paul Schroeder &
NHTSA seeks comment on whether, and to what degree, a rear seat belt warning would be effective. We seek comment on specific warning signal attributes that NHTSA could propose (e.g., duration of an audible warning), and how effective they might be, especially as compared to other possible signal attributes.
We also seek comment on how to quantify the effectiveness of a rear seat belt warning system, including data related to this. Because of the low prevalence and limited history with rear seat belt warnings, NHTSA has limited direct data on the effectiveness of rear seat belt warnings. Can we expect more or less of an increase than the 3-4% increase for enhanced front warnings? NHTSA requests any data or studies concerning the effectiveness of rear seat belt warnings. We also seek comment on balancing effectiveness with costs, technological feasibility, and acceptability.
With respect to comments that identify an innovative seat belt warning system differing from the current driver's seat belt warning and current production front and rear passenger seat belt warnings, NHTSA seeks comment on such possibilities, and the effectiveness of any such alternative.
D. Consumer Acceptance
21. NHTSA seeks comment on potential consumer acceptance concerns with a proposed seat belt warning system.
In order for a rear seat belt warning to have an impact on seat belt use, it must balance effectiveness with acceptability. The warning must be noticeable enough to prompt occupants to buckle their seat belts, but not so intrusive that the public does not accept the warning system, that an occupant will circumvent or disable it, or that the warning system could lead to driver distraction that could increase the risk of a crash. /98/
FOOTNOTE 98 DOT 2009 Belt Warning Study, supra, p. 2; Transportation Research Board Study, supra, p. 8. END FOOTNOTE
Consumer acceptance of any eventual seat belt warning requirements is an important consideration, given the potential safety benefits of rear seat belt warnings, the history of seat belt warning technologies, and the fact that consumers have not yet had widespread exposure to rear seat belt warnings.
The 2004 Transportation Research Board Report on technologies to increase seat belt use observed that, while limited, "the data available to date provide strongly converging evidence in support of both the potential effectiveness and consumer acceptance of many new seat belt use technologies[.]" /99/ As part of the research for the report, NHTSA conducted a limited number of focus group interviews with part-time and hard-core non-users. The report noted that "many part-time users interviewed by NHTSA--the primary target group for the technology--were receptive to the new systems. Nearly two-thirds rated the reminders "acceptable," and approximately 80 percent thought that they would be "effective." /100/
FOOTNOTE 99 Transportation Research Board Study, supra, pp. 75-76. END FOOTNOTE
FOOTNOTE 100 Id. p. 10. END FOOTNOTE
NHTSA's 2015 Survey of Principal Drivers of Vehicles with a Rear Seat Belt Reminder System also investigated the acceptability of rear seat belt warning systems. NHTSA surveyed (by telephone) drivers of vehicles with and without a rear seat belt warning system. /101/ The rear warning systems in these vehicles had a visual warning on start-up and an audio-visual change of status warning. The study found, among other things, that 81 percent of drivers of vehicles with a rear seat belt warning were "very satisfied" with the system warning at the beginning of a trip; less than 2 percent were dissatisfied. Seventy-eight percent of drivers were satisfied with the change-of-status warning during a trip; about 1 percent were dissatisfied. Among drivers of vehicles without a rear seat belt warning, attitudes towards rear belt warnings were generally positive as well: A majority (55%) indicated that it was important to them that their next vehicle be equipped with a rear belt warning system.
FOOTNOTE 101 The vehicles with seat belt warning systems were Volvos and certain
NHTSA seeks comment on what types of rear seat belt warnings consumers would accept. NHTSA seeks comment on specifications that would maximize effectiveness while still being acceptable to the public, as well as the potential for intrusive warnings to lead to driver distraction. NHTSA also seeks comment on how the potential for false positives can be minimized (because false positives can lead occupants to ignore or circumvent the warnings, or lead to driver distraction). NHTSA also seeks comment on the results of the 2015 survey, including whether and to what extent, selection bias might influence the results.
E. Technological and Economic Feasibility
22. NHTSA also seeks comment on the technological and economic feasibility of alternative rear seat belt warning systems.
We seek comment on the technological and economic challenges that might be posed by different types of warning systems, including the type of equipment and re-design they might necessitate. Seat belt latch and webbing spool-out sensors are already used by many manufacturers to comply with the existing driver seat belt requirements. We are aware that implementing a visual warning may require physical redesign of the instrument panel. Such redesign would have to take into account visibility, interaction with existing signals and displays, available space on the instrument panel, and effectiveness, as well as other factors. In some instances, a visual signal might be displayed as a telltale on the instrument panel or on the vehicle's information display screen. Manufacturers would also have to determine whether driver and rear passenger seat belt warning visual signals would be treated the same. Occupant detection might present technological challenges, but would probably not be necessary for a positive-only warning system. We recognize that larger vehicles with many rear designated seating positions may present challenges. We seek comment on these concerns, as well as other concerns.
We also seek comment about whether a rear seat belt warning would reliably detect a child restraint system attached by a child restraint anchorage system, or LATCH. /102/
FOOTNOTE 102 Many in the child passenger safety community refer to the child restraint anchorage system as the "LATCH" system, an abbreviation of the phrase "
F. Benefits and Costs
23. The agency has presented a wide variety of different potential alert systems, all with different cost and effectiveness profiles, and is not at this time conducting a cost-benefit analysis on any particular approach. However, many of the technologies discussed in this ANPRM are currently in use, either for front seat passengers or, in more limited models, rear seat passengers. NHTSA, therefore, seeks comment on the potential benefits and costs of the different types of rear seat belt warning system discussed in this notice, including those that provide a warning similar to the kinds of seat belt warnings that are provided in current-production vehicles in
G. Safety Act Criteria
24. MAP-21 instructs NHTSA to initiate a rulemaking proceeding for a rear seat belt warning system and to issue a final rule if it would meet the requirements in section 30111 of the Safety Act. NHTSA seeks comment on whether a proposed rear seat belt warning system would meet the requirements and considerations of 49 U.S.C. 30111.
H. Non-Regulatory Alternatives
25. If commenters believe that a proposed seat belt warning system would not meet the requirements and considerations of 49 U.S.C. 30111, NHTSA seeks comment on whether it should consider any non-regulatory approaches to address this issue.
For example, NHTSA might provide recognition through NCAP for vehicles equipped with a rear seat belt warning system. Other international NCAP programs, including Euro NCAP,
NHTSA could also issue voluntary guidelines for manufacturers. The guidelines could identify best practices for manufacturers who wish to equip vehicles with a rear seat belt warning system. The best practices could include the type of information the warning system should convey and the minimum durations of the warnings. NHTSA also seeks comment on whether there would be any other non-regulatory approaches that would be appropriate.
I. Removing the Driver's Seat Belt Warning Audible Signal Duration Upper Limit
26. NHTSA also seeks comment on removing the driver's seat belt warning audible signal duration upper limit.
FMVSS No. 208 currently requires a driver's seat belt warning with an audible warning lasting between four and eight seconds. Prior to the enactment of MAP-21, the agency could not require the audible warning to operate for more than 8 seconds. As discussed above,
Although NHTSA did not previously have the authority to require, or specify as a compliance option, a seat belt warning with an audible signal lasting more than 8 seconds, the agency facilitated the voluntary adoption of enhanced warnings through a series of legal interpretations that determined that the Safety Act did not prohibit manufacturers from using enhanced warning systems (e.g., systems with audible warnings that lasted more than 8 seconds) as long as the manufacturer differentiated the voluntarily-provided signal from the required signal (for example, by a clearly distinguishable lapse in time between the two signals).
Amending FMVSS No. 208 by removing the 8-second limitation would eliminate the need to differentiate between signals and give vehicle manufacturers greater flexibility in designing their seat belt warning systems. It would not affect the minimum required duration for the audible signal (4 seconds) and would not require manufacturers to make any changes to their existing seat belt warnings that comply with the existing requirements of FMVSS No. 208.
We seek comment on this.
VII. Regulatory Notices
This action has been determined to be significant under Executive Order 12866, as amended by Executive Order 13563, and the
VIII. Public Comment
How do I prepare and submit comments?
* To ensure that your comments are correctly filed in the Docket, please include the Docket Number found in the heading of this document in your comments.
* Your comments must not be more than 15 pages long. /103/ NHTSA established this limit to encourage you to write your primary comments in a concise fashion. However, you may attach necessary additional documents to your comments, and there is no limit on the length of the attachments.
FOOTNOTE 103 49 CFR 553.21. END FOOTNOTE
* Please organize your comments so they appear in the same order as the topics to which they respond appear in this document. Please identify comments by the number with which the relevant topic is associated in this document.
* If you are submitting comments electronically as a PDF (Adobe) file, NHTSA asks that the documents be submitted using the Optical Character Recognition (OCR) process, thus allowing NHTSA to search and copy certain portions of your submissions.
* Please note that pursuant to the Data Quality Act, in order for substantive data to be relied on and used by NHTSA, it must meet the information quality standards set forth in the OMB and DOT Data Quality Act guidelines. Accordingly, NHTSA encourages you to consult the guidelines in preparing your comments. DOT's guidelines may be accessed at https://www.transportation.gov/regulations/dot-information-dissemination-quality-guidelines.
Tips for Preparing Your Comments
When submitting comments, please remember to:
* Identify the rulemaking by docket number and other identifying information (subject heading,
* Explain why you agree or disagree, suggest alternatives, and substitute language for your requested changes.
* Describe any assumptions you make and provide any technical information and/or data that you used.
* If you estimate potential costs or burdens, explain how you arrived at your estimate in sufficient detail to allow for it to be reproduced.
* Provide specific examples to illustrate your concerns, and suggest alternatives.
* Explain your views as clearly as possible, avoiding the use of profanity or personal threats.
* To ensure that your comments are considered by the agency, make sure to submit them by the comment period deadline identified in the DATES section above.
For additional guidance on submitting effective comments, visit: https://www.regulations.gov/docs/Tips_For_Submitting_Effective_Comments.pdf.
How can I be sure that my comments were received?
If you wish Docket Management to notify you upon its receipt of your comments, enclose a self-addressed, stamped postcard in the envelope containing your comments. Upon receiving your comments, Docket Management will return the postcard by mail.
How do I submit confidential business information?
If you wish to submit any information under a claim of confidentiality, you should submit three copies of your complete submission, including the information you claim to be confidential business information, to the Chief Counsel, NHTSA, at the address given above under FOR FURTHER INFORMATION CONTACT. In addition, you should submit a copy, from which you have deleted the claimed confidential business information, to the docket at the address given above under ADDRESSES. When you send a comment containing information claimed to be confidential business information, you should include a cover letter setting forth the information specified in our confidential business information regulation. (49 CFR part 512)
Will the agency consider late comments?
We will consider all comments received before the close of business on the comment closing date indicated above under DATES. To the extent possible, we will also consider comments that the docket receives after that date. If the docket receives a comment too late for us to consider in developing a final rule (assuming that one is issued), we will consider that comment as an informal suggestion for future rulemaking action.
How can I read the comments submitted by other people?
You may read the comments received by the docket at the address given above under ADDRESSES. The hours of the docket are indicated above in the same location. You may also see the comments on the internet. To read the comments on the internet, go to http://www.regulations.gov. Follow the online instructions for accessing the dockets.
Please note that even after the comment closing date, we will continue to file relevant information in the docket as it becomes available. Further, some people may submit late comments. Accordingly, we recommend that you periodically check the Docket for new material. You can arrange with the docket to be notified when others file comments in the docket. See www.regulations.gov for more information.
[FR Doc. 2019-20644 Filed 9-26-19;
BILLING CODE 4910-59-P