How to operate a wheelchair safely outdoors<br>Stay on even surfaces. Uneven surfaces can make any wheelchair get off balance. Even when someone is pushing a wheelchair, an uneven surface can cause harm.
It is safe to use your wheelchair on stairs.
( z1 safe :ARG0 ( z2 use :ARG0 ( z3 you ) :ARG1 ( z4 wheelchair :poss z3 ) :location ( z5 stair ) ) )