Statutory Requirements

Public Utilities (Water Supply) Regulations

Potable water storage tanks which are not properly maintained can be a potential source of contamination. Under the Public Utilities (Water Supply) Regulations and Singapore Standard SS CP48 – Code of Practice for Water Services, any person responsible for the maintenance of any part of a water service installation having a water storage tank shall engage, at least once every 12 months, a licensed water service plumber to inspect, and where necessary to clean and disinfect, and certify the water storage tank. This is to ensure that:


1) The water storage tank is fit and safe for the storage of water for human consumption;
2) The water contained in the water storage tank is free from contamination or pollution and that there is no likelihood of such contamination or pollution;
3) Water samples taken from the water storage tanks pass the appropriate chemical and bacteriological examinations;
4) The water storage tank is properly maintained; and
5) There is no leakage and no likelihood of leakage in the water service installation, including the water storage tanks



Confined Space

All tanks, including water tanks, are classified as Confined Space, basically because  it is  enclosed, has no natural ventilation, no natural lighting and  with limited opening(s) for ingress/egress.


Legal definition: “confined space” means any chamber, tank, manhole, vat, silo, pit, pipe, flue or other enclosed space, in which —
(a) dangerous gases, vapours or fumes are liable to be present to such an extent as to involve a risk of fire or explosion, or persons being overcome thereby;
(b) the supply of air is inadequate, or is likely to be reduced to be inadequate, for sustaining life; or
(c) there is a risk of engulfment by material;


Workplace Safety & Health (Confined Space) Regulations 2009

Gazetted on 2nd October 2009, the Regulations take effect on 1st November, 2009. The ruling seeks to ensure safe working conditions in confined spaces.


Key provisions in the new Regulations include:


1) Displaying of warning signs;
2) Instituting requirements for confined space entry permit including gas checks by a competent person, approved and calibrated instruments, etc.;
3) Training of workers for work in confined spaces; and others.


In addition, CP84:2000 Code of Practice for Entry into and safe working in confined spaces must be observed.



The Legislation may be obtained, without charge, at Government Statue Online.

Code of Practices may be purchased from Singapore Standards eShop.

Workplace Safety & Health (Confined Space) Regulations 2009