Public liability insurance covers businesses from the risk of being sued by a member of the public in the event of an accident. It is essentially insurance that compensates people if they experience injury or damage resulting from lack of reasonable care by an insured business.
In the context of tourist accommodation, it may cover financial damages and legal expenses resulting from accidental bodily injury or damage to property, suffered by members of the public which have been caused by your employees or at your premises.
Public liability insurance and Employers' liability insurance are not the same. Employers' liability insurance is required by law upon employment by you of an employee. Public liability insurance is not required by law for most businesses, nor does NITB require you to have this for the purposes of certification. You may however wish to consider this and should contact either your existing insurers, an independent insurance broker or financial advisor for further information.