The Health, Safety and Welfare at Work Act 2005 – apart from other legislation e.g. Equal Status Act 2000, Employment Equality Act 1998-2011 and indeed Section 18 of the Fire Services Act 1981 – states;
11.—(1) Without prejudice to the generality of section 8 , every employer shall, in preparing and revising as necessary adequate plans and procedures to be followed and measures to be taken in the case of an emergency or serious and imminent danger—
(a) provide the necessary measures to be taken appropriate to the place of work for first aid, fire-fighting and the evacuation of employees and any other individual present in the place of work, taking account of the nature of the work being carried on and the size of the place of work,…
…(c) for the purposes of implementing the plans, procedures and measures referred to in this section and section 8
(i) designate employees who are required to implement those plans, procedures and measures, and
(ii) ensure that the number of those employees, their training and the equipment available to them are adequate, taking into account either or both the size of and specific hazards relating to the place of work.