3. For regulation 4(3) of the principal Regulations there shall be substituted the following paragraphs:
“(3) The Secretary of State may exempt any ship or description of ships from all or any of the provisions of these Regulations (as may be specified in the exemption) if he is satisfied that:
(a)compliance with such provision is either impracticable or unreasonable in the case of that ship or description of ships, and
(b)the exemption is subject to such conditions and limitations as will provide a level of safety equivalent to that provided by the provision or provisions from which exemption is being granted.
(4) The Secretary of State may, on giving reasonable notice, alter or cancel any exemption granted under paragraph (3) above.”