Just looking at the pictures, I'd call it "feasible" but not advisable. The hose is probably strong enough, as were the welded steel office chairs of resteryear. The rigging looks solid (bowline and clove hitches).
https://garethrhodes.files.wordpress.com/2014/01/20940_3.jpgBut, it would be suicide to try it with todays plastic and mesh chairs.
If I had to recreate the the attempt, I would forgo the office chair and tie the hose into any number of field expedient rescue or climbing harnesses.