64. (1) Where it is necessary for an employee to use personal protective equipment, the employer shall determine the conditions of use of such equipment, in particular the period for which it is worn, on the basis of—

(a) the seriousness of the risk,

(b) the frequency of the exposure to the risk,

(c) the characteristics of the workstation of the employee, and

(d) the adequacy of the personal protective equipment.

(2) An employer shall ensure that personal protective equipment is used only for the purposes specified, except in specific and exceptional circumstances.

(3) Where it is necessary for an employee to wear simultaneously more than one item of personal protective equipment, the employer shall ensure that such items of personal protective equipment are compatible with each other and continue to be effective against the risks involved.