It's a stair lift - you didn't say - the Minivator...
They mainly make stair-lifts for indoor use - no need to make them weatherproof.
It might work outdoors for a while but not for long I suspect.
However...
The Minivator 1000 Outdoor stairlift is fully waterproofed and designed to overcome the problems caused by external straight runs of stairs.
P Mason - Attorney at Law
October 2014