The Explosives Act 1875 etc. (Metrication and Miscellaneous Amendment) Regulations 1984 No. 510

Application to premises and plant in existence or under construction

6.  Where any premises or plant in existence or under construction immediately before the coming into operation of these Regulations complied with the requirements of the principal instruments as then in force, those premises or that plant shall be deemed to comply with the principal instruments as amended by these Regulations.