Without prejudice to section 21 of the Act -
(a) where employees are present in or at the same workplace to which this Part refers and they are employed by different employers, each employer shall ensure the safety of the employer's employees and for that purpose shall ensure that the matters that arise under the employer's control comply with this Part, and
(b) where 2 or more employers share the same workplace in which an explosive atmosphere may occur, the employer responsible for the workplace shall co-ordinate the implementation of all the measures required by this Part to be taken to protect employees from any risk from the explosive atmosphere.