(1) This section applies if a confined space must be cleared of contaminants to comply with section 56 (Entry to and work in confined spaces).
(2) A person in control of a workplace must ensure that, if appropriate, the confined space is cleared of all contaminants by using a suitable purging agent that displaces contaminants from the confined space.
(3) A person in control of a workplace must ensure that pure oxygen or a gas mixture in a concentration of more than 21% of oxygen by volume is not used to purge or ventilate the confined space.