Part of the GET WISE series from BHTA is a guide to making sure your wheelchair remains stable.
What is stability? Generally, for a wheelchair to remain stable, it must be upright on its wheels with the combined centre of mass of the wheelchair and user being within the wheelbase of the wheelchair. These guidelines should only be used in conjunction with the manufacturers owners’ manuals and instructions for safe use.
What affects stability? Ramps and slopes can present a high risk to users if they try to climb, descend or travel across slopes that are steeper than the safe working limit of the wheelchair. Appropriate gradients and surfaces should not cause problems if they are within the capability of the wheelchair. Wheelchairs should only be used on ramps or slopes that are less than the maximum safe slope specified by the manufacturer.
Note: it is important to talk to your local BHTA retailer or supplier. They will give you good advice regarding capability and suitability of each wheelchair.
Wherever possible, wheelchairs should be tested on any slopes that will be used regularly.
Steps, kerbs and soft ground When travelling up, down or across a slope, contact with relatively small obstacles can cause instability leading to tipping or sliding. Hitting obstacles can also cause the seated occupant to slide forwards or fall forwards out of the wheelchair. Use on soft ground can lead to similar problems, as small or narrow wheels tend to sink into the ground. Negotiating kerbs or steps should be undertaken following the manufacturers’ instructions, but always try to use dropped kerbs and ramps where possible.
Cushions The addition of some seat cushions can raise the centre of gravity of the wheelchair and reduce the stability of the wheelchair in all directions. The addition of a backrest cushion will move the centre of gravity forward, improving rearward stability but decreasing forward stability.
Seating systems Seating units fitted into wheelchairs, tilting seating units or reclining backrests can have similar effects on stability to the addition of cushions, by moving the user upwards and possibly forwards or rearwards within the wheelchair compared to the original seating position. This will affect stability in all directions.
Added weight The attachment of accessories or other items such as shopping bags, ventilators or oxygen cylinders hung or positioned on the rear of the wheelchair will move the combined centre of gravity of the user and wheelchair rearward. This may not cause problems on level ground, but it can make the wheelchair unstable when climbing a slope or ramp. Never carry passengers.
User body movement The stability forwards, rearwards and sideways can be reduced by the user moving their upper body or by leaning out to operate switches or pick something up. However, rearward stability can be improved when climbing slopes if the user can lean forward.
Click below to continue reading the BHTA guide to making sure your wheelchiar remains stable.