Seat belt reminders

What are they?

Seat belt reminders are intelligent, visual and audible devices that detect whether seat belts are in use in various seating positions and give out increasingly urgent warning signals until the belts are used. Based on the Swedish experience, the European Enhanced Vehicle-Safety Committee (EEVC) Working Group recommended in 2002 that [30]:

• Seat belt reminders should target part-time users, i.e. people who understand the value of a seat belt but sometimes do not use it.
• They should not affect the driveability of the vehicle.
• A combination of visual and sound signals should be used.
• The reminder signal should use multiple steps, i.e. build up progressively.
• Seat belt reminders should also be expanded to the rear seats

EuroNCAP has developed a seat belt reminder protocol along these lines (though requiring only a visual signal for the rear seat in the absence of seat occupancy information) and encourages their installation. Cars meeting the specification receive points which contribute to the star rating.

What road safety problem do they address?

Research studies indicate that the risk of dying in a crash could be reduced by about 60% by using the seat belt and by more, when belts and air bags are combined (WHO 2004). While most drivers in EU countries wear seat belts in the fronts of cars, a significant proportion involved in crashes are unrestrained, even in countries with highest seat belt use. Seat belt wearing levels in the rear seat are not high in most EU countries [21].

How effective?

User trials and research in Sweden and the United States have shown that seat belt reminders with advanced reminder systems with visual and audible warnings were the most effective systems for increasing seat belt use [21].

A Swedish study examined differences in driver’s seat belt use in cars with or without different reminder systems and found that 99% of drivers used their seat belt in cars with the most advanced reminders (in compliance with EuroNCAP criteria), 93% of drivers used their seat belt in cars equipped with “mild” reminders producing a visual and soft sound signal, 82% of drivers used their seat belt in cars without seat belt reminders.

Earlier US studies found a 7% increase in seat belt use among drivers of cars with seat belt reminders, compared with drivers of unequipped vehicles (Williams et al, 2002). A driver survey found that of the two thirds who activated the system, three quarters reported using their seat belt and nearly half of all respondents said their belt use had increased [57].

Seat belt reminders can help part-time users to develop habits of belt use. But they are likely to have little effect on hard-core non users who actively choose not to buckle up. More aggressive solutions, such as interlock systems, may be needed to encourage this small but important non user group to belt up [21].

Benefit to cost?

A cost-benefit analysis for the mandatory introduction of audible seat belt reminders for front seats in 2004 was undertaken by ETSC in 2004. It was based on the assumption that roughly 50% of fatally injured front seat car occupants killed in the EU did not wear seat belts and that audible seat belt reminders for the front seat could increase seat belt wearing among front seat occupants to 97%. After twelve years of introduction, the costs would amount to about 11 million Euro while the benefit would be 66 million Euro. The benefit to cost ratio of seat belt reminders was estimated at 6:1 [18]. A Belgian study by the Belgian Policy Research Centre for Traffic Safety has found that a seat belt reminder system would be beneficial to society even if it prompted only 5-15% of non users to fasten up over a period of ten years [7].

Who uses them?

Of all new cars tested by EuroNCAP since 2003, over 70% are fitted with seat belt reminders. Around 80% of new cars sold in Sweden in 2006 were fitted with seat belt reminders. Sweden has created a demand for this safety equipment nationally through its own in-house safety policy for staff travel and as one of the safety requirements of its road transport contracts. By 2010, the Swedish policy is that all new cars sold in Sweden should have seat belt reminders

Next steps for implementation?

There have been calls for the mandatory fitment of seat belt reminders in all seats in Europe, given the great potential of this technology. In 2005, the CARS 21 High Level Group included EU regulation on seat belt reminders in its 10 year road map for the automotive industry in Europe.

The European Transport Safety Council has called for their installation to be extended to all front seats, then to back seats. In parallel, retro-fitting of vehicles with seat belt reminders to all seats should be introduced [21].

The SUPREME project reports that ACEA, the European Automobile Manufacturers Association, has expressed its commitment to continue to equip progressively passenger cars of categories M1 and commercial vehicles with seatbelt reminders for the driver's seat believing that the majority of new models will be equipped accordingly by 01.01.09 at the latest and of new vehicles by 01.01.10 at the latest. ACEA will also provide on a regular basis statistics regarding the availability of seatbelt warning on vehicles registered in the EU.