For the purposes of section 16(2)(a) of the 1997 Act, an employer shall carry out, in compliance with section 19 of the Act, a risk assessment, taking account of -
(a) the specific effects and hazards of night work, and
(b) the risks to the safety and health of the employee concerned that attach to the work that a night worker is employed to do,
so as to determine whether that work involves special hazards or a heavy physical or mental strain.