When Donna drops by Harold's house for the second time, the first thing he does is wrap a quilt around her. Yet on her previous visit, they had both discussed how warm the house is, and that this is to protect Harold's orchids.
In the scene with Doctor Jacoby there is clearly a large sign saying "NO SMOKING OXYGEN IN USE" yet there are dozens of candles surrounding the hospital bed. It is unlikely any doctor or nurse would ignore this.