90.This section provides that in circumstances where the carrying out of the duties imposed by sections 53 to 56 and regulations under sections 57 and 58 (defined in section 79 as the “Chapter 1 duties”) would prevent a member of the armed forces of the Crown, a visiting force, a police constable or any other person of a description prescribed in regulations from carrying out their operational duties (as defined in subsection (4)), the Chapter 1 duties are temporarily suspended during that period. Subsection (3) provides that in these circumstances a person whose duties are temporarily suspended must still ensure so far as is possible the safety of relevant persons in respect of harm caused by fire.