Singapore legislation
Regulation 42
Regulation 42
General conditions
The following conditions shall be complied with in regard to every such chamber, other than an underground storage tank, as is referred to in rule 41:
the chamber shall be of brickwork of a thickness of not less than 35 centimetres, rendered inside with cement plaster of a thickness of not less than 2.5 centimetres and shall be completely enclosed except for a doorway 1.2 metres in height and 0.6 metre in width and a ventilator shaft of not more than 15 centimetres in diameter with openings at the top closed by fine mesh copper or brass wire gauze;
the chamber shall be so built that the cubic capacity below the ground level is equal to at least 1½ times the cubic content of the quantity of dangerous petroleum to be stored;
the door sill shall be at such a height from the floor level of the chamber that the cubic capacity of the chamber below the sill is equal to at least twice the cubic content of the quantity of dangerous petroleum to be stored;
the door shall be of steel or iron of a thickness of not less than 3 millimetres hung in a steel or iron frame;
the floor shall be laid in cement concrete at least 15 centimetres in thickness shall be water tight and shall slope to a small catch-pit; and
if the chamber be a separate building a copper lightning-conductor shall be provided leading to an earth-plate in a pit, well, river or the sea and shall be maintained in good order.