Breach of duty in English law

In English tort law, there can be no liability in negligence unless the claimant establishes both that they were owed a duty of care by the defendant, and that there has been a breach of that duty. The defendant is in breach of duty towards the claimant if their conduct fell short of the standard expected under the circumstances.
General standard of care
In order not to breach a duty of care, a defendant must generally meet the standard of a 'reasonable man' as Baron Alderson stated in Blyth v Birmingham Waterworks (1856) 11 Exch 781.
A reasonable person can be defined as 'the man on the Clapham omnibus' as Greer LJ explains in Hall v Brooklands Auto-Racing Club (1933) 1 KB 205. Lord Steyn describes the term as 'commuters on the London Underground' (MacFarlane v. Tayside Health Board (1999) 3 WLR).
This is an objective standard, based on an average person. It does not require perfection, but takes into account that an...