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CR 215: Benefits of Retrofitting Seat Belt Reminder Systems to Australian Passenger Vehicles (2004)


The aim of this study was to determine the potential benefits of retrofitting a seat belt reminder device, in addition to the current fivesecond warning light, to existing passenger vehicles in the Australian fleet. It has been argued that the fivesecond warning is lost among the various warning lights that display when the ignition is activated, and that a more persistent reminder would lead to improvements in seat belt wearing in Australia. A more aggressive reminder system therefore would seem warranted to help further reduce road trauma in Australia.

Australia has played a leading role historically in seat belt wearing and as a result of previous government legislation, seat belt wearing rates in the front seat have been consistently around 95% for the last decade. Current nonwearing rates in casualty crashes, however, are much higher than exposure figures, with 33% of fatally injured and 19% of seriously injured occupants being unbelted. These statistics reflect the effectiveness of seat belts in preventing injuries, and possibly a tendency for unrestrained drivers to be higher risk takers.

The National Road Safety Action Plan for 2003 and 2004 identifies seat belt reminder systems in new vehicles as a priority area for road safety improvement. An earlier report by the same authors (Fildes, Fitzharris, Koppel, & Vulcan, 2002) showed that requiring compulsory seat belt reminder systems that were more aggressive than the current warning light required by Australian Design Rule (ADR) 69 was likely to be costbeneficial if the reminders were fitted to new vehicles when being manufactured.

Increases in new vehicle safety can bring substantial gains in the long term, but it takes many years for these benefits to affect the bulk of the vehicle fleet. This raises the question of whether retrofitting to existing vehicles would also be a costeffective option.

In theory, retrofitting of seat belt reminder systems could be either voluntary or mandatory, although voluntary retrofitting would be likely to have a very limited impact. Those most likely to benefit would probably be least likely to fit the device. It is unlikely that any form of mandatory retrofitting would come in until the ADRs had been changed to make more aggressive seat belt reminder systems compulsory in new vehicles. Within the Australian federal system, the Commonwealth is responsible for regulating standards for new vehicles, and state and territory governments normally regulate inservice vehicle standards. For example, the Western Australian Government requires the fitment of engine immobilisers upon the transfer of registration of used vehicles; and a similar scheme could potentially be used to facilitate the retrofitting of seat belt reminder devices to appropriate vehicles within each Australian state and territory.

Within the context of the earlier report by Fildes et al. (2002), an arbitrary assumption was made for the purpose of this report that manufacturers would be required to fit a more aggressive reminder system than the current fivesecond warning light at some time in the near future. This report then analyses the potential benefits of retrofitting a seat belt reminder system to passenger vehicles up to ten years of age. The ten year vehicle age limit was selected for four principal reasons: the potential HARM savings associated with belt use were calculated for vehicles fitted with at least a frontal driver airbag; vehicles older than ten years may have a useful life less than the retrofitted device itself, therefore limiting potential benefits of a retrofitting strategy; no structural alterations to the vehicle should be required in fitting the device, and this may be more achievable with a narrow vehicle cohort; and finally the device must be able to be fitted to every vehicle in the selected cohort. These requirements may act in concert to improve the feasibility and public acceptance of a retrofitting strategy.

Recently there have been significant advances in technology to remind people to buckle up. Ford has recently developed The BeltminderTM that comprises a flashing light on the dashboard and a warning tone of reasonable intensity. Variants of this include an option for the flashing rate and tone intensity to increase at higher travel speeds. The Insurance Institute of Highway Safety and Ford have reported increased wearing rates in the United States of around 17% for the BeltminderTM system. Further highlighting the interest in seat belt reminder systems, the European New Car Assessment Program (EuroNCAP) has commenced providing added point bonuses for cars they assess for crashworthiness if vehicles are fitted with seat belt reminders, and the Australian NCAP program has followed suit. The Swedish Insurance Industry recently held a competition aimed at locating an inexpensive retrofit seat belt reminder system for the driver. The winners of the competition are currently developing the device at Autoliv Research in Gothenburg. It is timely therefore to examine the feasibility of retrofitting seat belt reminder systems in the Australian fleet.

Calculating benefits and device costs

The benefits of seat belt reminders were computed using the HARM Reduction method developed in Australia by the Monash University Accident Research Centre (MUARC) and used for previous benefit studies for the Department of Transport and Regional Services. HARM is a metric for quantifying injury costs from road trauma. It is a function of the number and type of injuries sustained, expressed in terms of community costs.

In the absence of an available massproduced seat belt reminder device amenable to retrofitting, benefits were calculated using four levels of effectiveness from 10% to 40%, and three implementation strategies (driveronly, front occupants, all occupants). The term percent effectiveness refers to the percent improvement in current belt wearing rates afforded by the device. It was estimated that a device that afforded a 40% effectiveness rate would increase seat belt wearing to 97% in the front seats.

Annual HARM benefits were computed for these three implementation strategies and four effectiveness rates. Using a discount rate of 5%, the benefits varied from around $12 million to $72 million annually if all vehicles in the fleet were fitted with the devices, equating to an annual HARM reduction of between 0.14% and 0.81%.

In the absence of per unit device costs, estimates of $25$65 at $10 increments were used. Calculations were performed using costs excluding GST. Unit HARM benefits were calculated using three levels of discount factors (4%, 5% and 7%) and a device life of 10 years. In the light of a recent report by the Bureau of Transport and Regional Economics (BTRE, 2001), it was argued that a 5% discount rate was most appropriate for this analysis.

Download Complete Document: Belt_Analysis_9 [PDFPDF: 384 KB]

Type: Research and Analysis Report
Sub Type: Consultant Report
Author(s): Fildes B, Fitzharris M, Koppel S, Vulcan P
ISBN: 0 642 25517 2
ISSN: 1445-4467
Topics: Economic, Vehicle design
Publication Date: 01/01/04


Last Updated: 6 May, 2013