I work for the NHS, I work in families homes and not on a ward. I am an asthmatic, one of my triggers is cigarette smoke and until recently, this has not been a problem. But now one of the homes we go into has a bathroom that is very obviously used by a smoker. The bathroom contains the only toilet in the house and we are expected to bath the child we are caring for. I recently had a nasty chest infection and said at my back-to-work interview that cigarette smoke is a trigger and requested that I did not go to this family (I work in a team, there are others that can go), I am still be regularly rostered on to go to this family. Can I say no?