Section 70: Dangerous fumes and lack of oxygen

70. Dangerous fumes and lack of oxygen (1) The provisions of subsections (2) to (7) of this section shall have effect where work has to be done inside any vessel, tank, pit or similar confined space in which dangerous fumes are liable to be present to such an extent as to involve risk of persons being overcome thereby. (2) The confined space shall, unless there is other adequate means of egress, be provided with a manhole, which may be rectangular, oval or circular in shape, and shall be not less than 450 millimetres long and 400 millimetres wide or (if circular) not less than 450 millimetres in diameter, or in the case of tank wagons and other mobile plant, not less than 400 millimetres long and 350 millimetres wide or (if circular) not less than 400 millimetres in diameter. (3) Subject to subsection (4), no person shall enter or remain in, and no person shall require, instruct or direct any person to enter or remain in, the confined space for any purpose unless the person entering or remaining in the confined space is wearing a suitable breathing apparatus (which shall not include a respirator) and has been authorised to enter by a competent person, and, where practicable, is wearing a belt with a rope securely attached and a person keeping watch outside and capable of pulling him out, is holding the free end of the rope. (4) Where the confined space has been certified by a competent person as being, for a specified period, safe for entry without breathing apparatus and the period so specified has not expired, subsection (3) shall not apply, but no person shall enter or remain in the space unless he has been warned when that period will expire. (5) A confined space shall not be certified under subsection (4) unless— (a) effective steps have been taken to prevent any ingress of dangerous fumes; O2 – 49 [Issue 1] Occupational Safety and Health Act (b) any sludge or other deposit liable to give off dangerous fumes has been removed and the space contains no other material liable to give off dangerous fumes in significant quantities; and (c) the space has been adequately ventilated and tested for dangerous fumes and has a supply of air adequate for breathing. (6) There shall be provided and kept readily available a sufficient supply of suitable breathing apparatus, belts and ropes, and of suitable reviving apparatus and oxygen, and the apparatus, belts and ropes shall be properly maintained and shall be thoroughly examined, at least once every 3 months by a competent person who shall make a report on every such examination, which shall be kept available for inspection. (7) A sufficient number of employees shall be trained and given practice in the use of the apparatus specified in subsection (6) and in a method of restoring breathing. (8) No person shall enter or remain in any confined space in which the proportion of oxygen in the air is liable to have been substantially reduced unless— (a) he is wearing a suitable breathing apparatus; or (b) the space has been and remains adequately ventilated and a competent person has tested and certified it as safe for entry without breathing apparatus.