By Missy Ball, MT, PT, ATP, Convaid | R82 Seating & Mobility Expert | Globally, 1.3 million people die in road crashes per year. In the US, approximately 37,000 people die per year and 2.35 million are either injured or disabled. According to the NHTSA, a third of fatalities are a result of drunk driving, half are secondary to lack of wearing seat belts, 1 in 4 deaths are due to excess speed and 10% are a result of distracted driving. In 2005, experts found motor vehicle crashes to be the leading cause of death in Americans 3-33 years old. With the mandate of the pelvic/shoulder belts by Federal Motor Vehicle Safety Standards (FMVSS), there was a 45% reduction in fatalities and 50% reduction in disabling injury to front seat occupants age five and older.
Federal Motor Vehicle Safety Standards have been established and are regulated for people using seats provided by a vehicle manufacturer. Presently there are no federal safety standards for wheelchairs used as a seat in a motor vehicle or for the tie-down and restraint systems (U.S. Dep of Transportation 1999).
The NHTSA’s National Center for Statistics and Analysis (NCSA) examined data over 10 years ago and found about 2,294 injuries/deaths occurred to individuals in wheelchairs in motor vehicles between 1991-1995 as a result of improper securement (lack of attaching all 4 tie-down straps) of occupied wheelchair in vehicle. One study reported a 45 time higher injury rate for occupants in wheeled mobility in motor vehicles compared to the general population seated in vehicle seat within a 100,000 mile period (NHTSA 2009)(RESNA White Paper).
Due to this lack of federal safety standards for wheelchairs, several groups have collaborated and developed recommendations for best practice for wheelchair transport in motor vehicles including SAE (Society of Automotive Engineers), ANSI, and RESNA(Rehabilitation Engineering and Assistive Technology Society of North America) and ISO (International Standards Organization). WC-18, WC-19, and WC-20 are the product of this collaboration. WC-18 (RESNA WC Volume 4:2012, Section 18) or (SAE J2249) promotes the design, testing, installation and use of wheelchair tie-down and occupant restraint systems (WTORS) that provide frontal crash protection for forward facing occupants in a wheelchair that is comparable to that provided by vehicle manufacturers.
The WTORS is tested at 48kph (30 mph) on sled with frontal impact using an 85kg (185lb) surrogate wheelchair and adult male dummy weighing 78kg (172 lbs) to dynamically test the wheelchair tie-down occupant restraint system. This standard allows compliance with four-point, strap-type tie-downs and docking systems. The WTORS must include a 3 point pelvic/shoulder belt restraint with vehicle anchored pelvic belt. 2 frontal impact tests must be conducted and passed to meet standard for WTORS as of December 2015, ensuring effective securement of wheelchair in vehicle during 30 mph frontal crash.
In 2000, ANSI/RESNA developed WC-19 (Wheelchair Used as Seat in Motor Vehicle) to address wheelchair design and performance when used as a seat in a motor vehicle. It applies to wheelchair design features that reduce error in securing wheelchair with four point, tie-down systems. Standard applies to manual, power, scooters, tilt-in-space chairs and specialized mobile seating bases with removable seat inserts. The following comes from RESNA’s Position Paper on Wheelchairs Used as Seats in Motor Vehicles.
The wheelchair will have the following:
- 4 permanent labeled securement points that can withstand forces at 30mph and 20g impact
- Specific securement geometry to allow a one-hand attachment of tie-down hooks from system
- Anchor points for a wheelchair-anchored crashworthy pelvic belt and an interface on this belt to connect a vehicle-anchored shoulder belt at the occupant’s hip
- Clear tie-down pathway between anchor points on vehicle floor and securement points on wheelchair (with angles of 30-45* from horizontal if possible, rear tie down straps best if located directly behind securement points on wheelchair and front slightly wider)
- Base frame and seating system with securement points which have been successfully crash tested at 30mph, 20g frontal impact with appropriate size dummy using four point strap tie-down system
- Measure of wheelchair lateral stability when secured with four-point, strap tie-down system forward facing
- Minimal sharp points and edges that could impact occupant or belts
— Sufficiently high back support/headrest
— Crash- worthy wheelchair integrated 5 pt. harness
WC- 20 (Wheelchair Seating Systems for Use in Motor Vehicles) tests the seating system alone separate from the frame base. Seating systems are installed on a surrogate wheelchair frame designed to withstand a 30 mph, 20 g frontal sled crash. A complete seating system consists of a seat, back, attaching hardware and may or may not include positioning supports. If seating system passes WC20 testing it should be mounted on WC 19 frame for best results. WC-20 addresses adults and children with total body mass of greater than 23 kg (51lbs).
Regarding postural supports refer to the following:
- Parts weighing greater than 100g (3.5oz) must be firmly attach to wheelchair to avoid breakage
- Any parts likely to contact person in wheelchair must be covered with high density padding
- Only contact bony parts of body with occupant restraint belts: pelvic belt low and across pelvis and shoulder belt crossing collar bone, breast bone(sternum) and anchored near hip
- SUB ASIS bar – do not use in travel if possible; use 4 pt. belt or 2 belts anchored in 2 locations rearward and downward
- Headrests should be close to head and no more than 2” from rear of head
- Headrest height should be positioned with middle of pad aligned with top of ears
- Headrest should be firmly attached so it does not break free; ensure occupant’s head cannot go around or under pad
- Avoid anterior head support or neck support- if essential only use soft neck collar not attached to wheelchair
In conclusion, using wheelchairs and seating systems that have undergone such rigorous testing provides a much greater degree of safety for end users while in motor vehicle transport during regular driving and during sharp turns, quick stops or when in an accident. Wheelchair users have a right to the same degree of safety as the rest of society. Transit allows them access to the community for school, work, recreation, and exploration which enriches their lives and the community.
Convaid manufacturer performs in-house crash testing, which is rare, as well as testing off site at the University of Michigan Transportation Research Institute. Their line of chairs including the EZ Rider, Cruiser, Rodeo, Safari and Trekker, all are crash tested WC-19 approved. R82 products including Multi frame, Multi frame X, and Stingray are also crash tested and ISO 7176-19 approved, hence ensuring the child, adolescent, or adult in these systems are receiving best practice guidelines for transport in motor vehicles.