From Law wiki, the wiki for law research

[1958] 2 QB 265. The claimant sued the defendant for breach of his duty under the occupiers liability act (1957) to 'take such care as is reasonable in the circumstances' to ensure his safety. What had happened was the the claimant had pulled hard on a doorhandle -- fitted by the defendant himself -- which had come away from the door, with the effect that the claimant fell down some steps and was injured.

The question at issue was whether the defendant was in breach of the duty imposed by the Act. His duty was held to be to fit the doorhandle to the standard of a reasonably competent carpenter. It was not necessary that he work to the same standard as a professional tradesman working for reward, nor was it sufficient that he do the best that could be expected of an ordinary householder with no particular DIY skills.

The case is one of a number which is taken to establish that the standard of care required to discharge aduty of care is objective -- it does not depend on the capabilities or knowledge of the defendant.