Minivan Conversions | Full Size Conversion Van | Handicapped Vans
Information on Minivans Conversions, Handicapped Vans, and Wheelchair Accessible Adaptive Equipment
Let's confuse things a bit by first not discussing how to safely ride in your wheelchair. Rather, I want to try to convince you to not ride in your wheelchair in the first place. I know there are situations where the person just cannot safely or independently transfer. As part of a comprehensive evaluation, the driver rehabilitation specialist should look at your ability to transfer into a vehicle's seat. Whenever possible, and it is safe to do so, the person in a wheelchair should transfer into one of the vehicle’s original (OEM) seats. The reason is that very few wheelchairs are designed to withstand the forces of a crash, do not have the proper head restraints to prevent neck injuries, and properly securing the occupant with a seat belt can be very difficult. Car manufacturers must follow Standard No. 207 in designing a car seat and Standard No. 202 in designing a car seat's head restraints. These are federally mandated legal safety standards that all new vehicles must comply with. Most of us take for granted that vehicle seats are designed to withstand the forces imposed from a car crash. A wheelchair, on the other hand, does not and is not designed to meet those standards.
You can watch crash videos on the web and see the results for yourself. Manual wheelchairs especially are prone to failure in a vehicle crash. They appear to disintegrate during a crash. An exemption to these federally mandated safety standards exists that allows consumers to ride in a car from their wheelchair provided a lap and shoulder belt are used. Many times it is going to be hard to properly secure the occupant when riding in a wheelchair. The wheelchair’s armrests often prevent good belt fit. The location of the wheelchair in the vehicle, e.g. how far away it is from the vehicle's anchor points on the wall, can also make proper belt fit difficult. Wheelchair drivers, those who cannot transfer and also cannot fasten their own seatbelt, will have the hardest time in properly securing themselves. You can read the results of NHTSA's research into wheelchair occupant restraints in 2002. The one sentence that jumps out at you is on the second page of the report (page 84), "A number of 2,494 persons were injured or killed over a 5-year period as a result of improper or no securement of the wheelchair occupant." Here is an interesting power point file where NHTSA in 2007 is looking into the difficulties of properly securing wheelchair drivers. The following interesting observations are noted in the presentation:
Slide 6, in passing the 49CFR595 exemption, it was thought that requiring a wheelchair occupant to use FMVSS 209/210 lap and shoulder belt system would fix the issue of occupant restraints. That was 2001. In 2007 and even to this day, this issue hasn't been solved, especially for wheelchair drivers.
Starting around slide 16, you'll get to see pictures of how wheelchair drivers are often secured in the real world. Not at all like what the typical person riding in the OEM seat and using the standard seat belts experiences.
Slide 21, "Restraints are often an afterthought in the modification process." Even though the solutions are limited and sometimes non existent, even though wheelchair designs make the job difficult to impossible at times, this is the biggest problem in my opinion.
Starting around slide 35, you'll see the results of some tests that try to copy what wheelchair drivers are using for occupant restraint systems. The results aren't great.
In coming up with the legal exemptions to the safety standards, NHTSA weighed the downside of more vehicular crash deaths and injuries with the benefits of getting people with disabilities out into the community. Since the law was passed its obvious the benefits of getting people with disabilities out into the community won. That’s a very good thing. You should just be aware of the risks associated with riding in a wheelchair before making that decision and should know all of your options to mitigate the risks. When possible and if it makes sense with your physical abilities, transfer to a crash tested seat. When that is not possible, then try to get the most crash resistant wheelchair you can. The wheelchair and occupant restraint system should be analyzed by the driver rehabilitation specialist during the driver evaluation. You should also discuss this with the vehicle modifier during the modification process. As is too often the case, this should not be an afterthought that is left to the end.
The following products are available to assist with transfers:
A good resource for information on the latest developments in wheelchair transportation safety is the RERCWTS. Restraint systems put the occupant in a forward facing position because the majority of vehicle crashes are forward impact.
Forces required to restrain a wheelchair and occupant are proportional to mass and change in velocity. A good website that discusses the physics of car crashes is here. From physics, Force = Mass x Acceleration (in this case deceleration). The force to stop your body and wheelchair must be provided by the restraint system. If the restraint system cannot handle the forces, you will not be restrained and bad things will happen. Deceleration is the rate of change from a faster initial speed to a slower one, in our case zero or a complete stop. The initial velocity is the car speed prior to the crash. It's the amount of time (or stopping distance) that is takes to go to a complete stop that determines the rate of deceleration for a given initial speed. Nothing fancy here. Stop immediately by hitting a brick wall and you decelerate very quickly = large restraint forces. Hit another car with a glancing blow and coast to a stop 30 ft later and you decelerate not as fast = smaller restraint forces. The change in velocity depends on factors such as initial speed (faster you're traveling the larger the stopping force), time to come to a stop (hitting a brick wall or large tree is more severe than a glancing blow with another car), stopping distance (or converted to time in how long it takes to come to a stop), vehicle crush (this lessens the severity of hitting a brick wall because the stopping distance, assuming the brick wall doesn't move, is the amount of front end crush. Think Volvo car crash commercial.), and belt stretch (belts are designed with some stretch to them that prolongs the time for your body to come to a complete stop).
The restraint system protects the occupant by: preventing the occupant from being ejected from the vehicle, motion is restricted to prevent hitting objects in the vehicle as well as whiplash effect, increases time for the occupant to come to a stop (belt stretch).
The restraint system works by securing the wheelchair to the vehicle using four point strap tie downs or an electric docking station, restrains the occupant to the vehicle or to the wheelchair, and removes loose accessories and parts that can injury the occupant such as laptop trays and communication devices.
Retractable versus non retractable belts: The retractable belts offer move freedom of movement and help greatly with stowing unused belts. Non retractable belts should be used with occupants who have difficulty with upper body control. However, it is important to remember that a seat belt is not a postural support belt, and a dedicated postural support belt in combination with safety belts should be used when required.
The standard that applies to the design of these safety systems is SAE J2249 Wheelchair Tiedowns and Occupant Restraint Systems (WTORS)
Crash worthiness is simulated by a sled test 30mph, 20g. The 20g is the deceleration force (change in velocity), while 30mph is the initial velocity. 95% of all vehicle crashes are estimate to be less than the severity of a 30mph, 20g crash. Also it is on the border of survivability for the human body. Wheelchair and occupant restraint systems able to withstand forces more severe than the 30mph, 20g sled test would be of no real benefit because the human body is very unlikely to survive them anyway.
Note: manual strap tie downs are never used to secure a wheelchair in the driver position. Just in case that needed to be said.
inexpensive, can be used with almost any wheelchair (may require additional straps), don't add any equipment to the wheelchair (see disadvantages of electric restraint)
can be difficult to find good securement points on the wheelchair, require assistance from a person who can reach down and manipulate the straps (some caregivers cannot physically do this), tie downs get run over and walked upon damaging their integrity, takes a while to secure as opposed to an electric wheelchair docking station
Faster to secure the wheelchair, independent securement (especially needed in driver position), minimizes human errors
More expensive, hardware added to wheelchair (for manual wheelchairs the hardware adds weight and prevents the chair from being folded, for electric wheelchairs the hardware reduces the ground clearance), cannot be used all all wheelchairs (manufacturers state specific wheelchair models that work with their equipment), cannot be used with a ANSI/RESNA WC-19 lap and shoulder belt
A three point occupant restraint is utilized to properly secure the wheelchair occupant. The lap belt is secured by anchor points on either side of the occupant (2 points). The shoulder belt is secured to an anchor point on the vehicle (1 point, so 2+1=3) and on the other end to the lap belt. Note: The different types of seatbelts are: type 1 system = lap belt only (not legal since the 80's), type 2 system = lap belt and separate shoulder belt (although not allowed in new cars, many wheelchair occupants will need this style as opposed to type 2A due to their wheelchair), type 2A system = lap and shoulder belt are combined in the same belt (current standard, best because it ensures lap and shoulder belt will be used).
the lap belt attaches directly to the floor track. When used with a separate shoulder belt to form a complete system the occupant restraint is completely separate from the wheelchair restraint.
the lap belt attaches directly to the rear wheelchair restraints. When used with a separate shoulder belt to form a complete system the occupant restraint is integrated into the wheelchair restraint.
In a ANSI/RESNA WC-19 wheelchair, the lap belt is anchored to the wheelchair itself. Note: it's very important to know if your lap belt is a crash tested safety belt. A positioning belt may look like a car safety belt but will come loose in a car crash. The shoulder belt attaches to the lap belt with a standard pin interface. Note: It's important to realize that the occupant restraint forces will therefore be largely carried by the wheelchair restraint system. Electric wheelchair docking stations are not rated to carry this additional load. You must use a occupant restraint system that anchors to the vehicle in combination with the electric wheelchair docking station.
Usually the passenger is restrained in the cargo area of the van but sometimes the right front passenger seat is removed to allow the passenger to ride up front.
Wheelchairs are normally secured by 4 point manual strap system. Although an electric wheelchair docking station can be used, it might be difficult to maneuver the wheelchair into especially in a passenger only designed minivan such as a Braun CompanionVan® with limited space.
A 3 point restraint system is used. The type of system will depend in part on the wheelchair, whether it is WC-19 compliant, and whether the armrests will interfere with the use of the OEM combination lap and shoulder belt.
Wheelchair drivers can often be difficult to impossible to properly secure especially if the driver cannot buckle their seat belts.
An electric wheelchair docking station must be used to secure the wheelchair.
A 3 point restraint system is used. The type of system will depend in part on the driver's abilities and whether the armrests and wheelchair frame will interfere with the use of the OEM combination lap and shoulder belt. A female seatbelt stalk is attached to the floor near the wheelchair. If the driver can buckle their own seatbelt, the OEM seatbelt should be used if the wheelchair allows. Otherwise separate lap and shoulder belts are employed. The situation becomes very tricky for clients who cannot manage their own seatbelts. What is called the "drive-in" method is often used. The lap and shoulder belts are attached to the female stalk. Enough slack needs to be on the seatbelts so that it can held up by the steering wheel. The driver then drives into the seatbelt. Often the belt will not properly fit the client, will go around wheelchair frame members, and will not be pulled tight but there are few alternatives.
Sure-Lok
866 787-3565
www.sure-lok.com
Q’Straint
800 987-9987
www.qstraint.com
EZ Lock, Inc.
225 926-2403
www.ezlock.net/
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