In order to claim personal injury another party must be responsible in law or at least partly responsible for the actions that led to the injury being sustained. This may be because they have been plainly negligent and perhaps because they are in breach of some statutory duty owed to you. Negligence involves breach of a duty of care owed to you by the other party. The injury / loss must have been sustained as a direct result of the breach and it have been foreseeable that it would occur given the particular circumstances.
