Hong Kong Regulations

FACTORIES AND INDUSTRIAL UNDERTAKINGS (WORK IN COMPRESSED AIR) REGULATIONS - REGULATION 9

Use of man-locks

When the pressure in a working chamber exceeds 14 pounds per square inch-

   (a)  the man-lock shall, subject to paragraph (b), be used solely for the
        compression or decompression of persons;

   (b)  where it is not reasonably practicable to provide a separate man-lock
        for persons only, the single man-lock giving access to the
        working chamber shall not be used simultaneously for the compression
        or decompression of persons and the passage of plant or material other
        than tools or instruments carried by hand by persons for the purposes
        of the construction work: Provided that in the case of an emergency a
        single man-lock may be used simultaneously for the compression or
        decompression of persons and the passage of plant or material, and
        where the man-lock is so used the contractor shall keep a record
        signed by him of such use and particulars of the emergency;

   (c)  a 'blister' type man-lock shall be used for timed decompression only
        when the total decompression time does not exceed 20 minutes.