What if I have a very heavy wheelchair? Will the wheelchair tiedowns be strong enough?
WC18 requires dynamic testing of wheelchair securement systems in a 30-mph frontal impact using a rigid surrogate wheelchair that weighs 187 lb with an integrated, wheelchair-anchored lap belt. Clearly, some commercial wheelchairs weigh more than this surrogate wheelchair. In addition, if wheelchair occupants use integrated seatbelt restraints that anchor to the wheelchair or even wheelchair-attached postural belts, the forces on the wheelchair securement system will be larger.
So in a really severe crash, someone using a very heavy wheelchair could be at higher risk of tiedown failure than someone using a lighter wheelchair. However, US crash data show that 95% of the crashes in the US are lower severity than the 30-mph crash test specified in the standards, even in vans and minivans. The likelihood of such a severe crash is even lower in larger vehicles such as school buses and transit buses. So the tiedowns should work in most crashes even with a very heavy wheelchair. To ease concern when traveling in vans and minivans, additional tiedown straps could be installed for use with a heavier WC19-compliant wheelchair.
Remember that WC19 requires that compliant wheelchairs be successfully crash tested at 30 mph. Thus, even heavy WC19-compliant wheelchairs have demonstrated that they can deal with the forces generated by a 30-mph frontal crash using the securement points provided and specified in the manufacturers literature. Therefore, using a heavy wheelchair that has been tested to the WC19 standard will reduce the risk of ineffective wheelchair securement for most real-world crashes. A larger concern is people traveling in heavy wheelchairs that are not compliant with WC19, because the wheelchair may not be strong enough to remain intact during a crash.