A workman who is employed by a contractor to do work in a building or on a site which is occupied by a third party and who suffers injury while working there may, subject to any contributory negligence on his part, have a claim against both the employer and the occupier.

Commonsense principles are used to apportion liability (see for example Andrews v. Initial Cleaning Services Ltd and anor CA 2000 ICR 166, CA in which the employers were held to have had 75 per cent responsibility for an accident with the occupiers only 25 per cent responsible and Makepeace v. Evans Brothers (Reading) & anor CA 2001 ICR 241 in which a painter who was injured when a scaffold tower collapsed was held to be 25 per cent responsible himself with the employer being responsible for the other 75 per cent and the site occupier having no liability at all).