Singapore legislation
Regulation 26
of Workplace Safety and Health (General Provisions) Regulations
Regulation 26
Precautions with regard to explosive or flammable dust, gas, vapour or substance
Subregulation 1
Where any process in a plant used in a workplace gives rise to dust, gas, vapour or substance that may escape into any place of work and the dust, gas, vapour or substance that may escape is of such a character and is to such an extent as to be liable to explode on ignition —
all reasonably practicable steps shall be taken to prevent such an explosion —
by enclosure of the plant used in the process;
by removal or prevention of accumulation of the dust, gas, vapour or substance;
by exclusion or effective enclosure of possible sources of ignition; or
by the use of suitable flame-proof equipment; and
unless the plant in which the process is carried out is so constructed as to withstand the pressure likely to be produced by any such explosion, all reasonably practicable steps shall be taken to restrict the spread and effects of such an explosion by the provision of chokes, baffles and vents, or other equally effective appliances in the plant.
Subregulation 2
Where any part of a plant in a workplace contains any explosive or flammable gas or vapour under pressure greater than atmospheric pressure, that part shall not be opened, unless it is positively isolated, depressurised and vented to a safe location, and where necessary, purged to remove any residual gas or vapour.
Subregulation 3
No plant, tank or vessel in a workplace that contains, or has contained, any explosive or flammable substance shall be subjected to —
any welding, brazing or soldering operation;
any cutting operation which involves the application of heat; or
any operation involving the application of heat for the purpose of taking apart or removing the plant, tank or vessel or any part of it,until all reasonably practicable steps have been taken to remove the substance and any fumes, gas or vapour arising from it, or to render the substance and fumes, gas or vapour non-explosive and non-flammable.
Subregulation 4
If any plant, tank or vessel in a workplace has been subjected to any operation referred to in paragraph (3)(a), (b) or (c), no explosive or flammable substance shall be allowed to enter the plant, tank or vessel until the metal has cooled sufficiently to prevent any risk of igniting the substance.
Subregulation 5
No plant, tank or vessel in a workplace which contains, or has contained, any explosive or flammable substance shall be subjected to any operation referred to in paragraph (3)(a), (b) or (c) unless such plant, tank or vessel has been inspected and a competent person has certified that —
it is free from —
any explosive or flammable substance; and
any fumes, gas or vapour arising from any such substance; or
any explosive or flammable substance, and any fumes, gas or vapour arising from any such substance, have been rendered non-explosive and non-flammable,and that it is safe for the operation to be carried out.
Subregulation 6
Any certificate issued by a competent person under paragraph (5) in respect of any workplace referred to in that paragraph shall be kept available at all times for inspection by an inspector.
Subregulation 7
It shall be the duty of the occupier of a workplace referred to in paragraphs (1) to (6) to comply with those paragraphs.
Subregulation 8
It shall be the duty of a competent person to exercise all due diligence in making any inspection and certification under this regulation.