Water Quality

Aerosol-generating Systems (AGS)

Cooling towers, a type of AGS, are used in many commercial buildings and factories, for comfort cooling or industrial process cooling. When a cooling tower is in operation, water aerosols are emitted from the top of the cooling tower, along with exhaust air. These aerosols may contain Legionella bacteria if the water in the cooling tower is not adequately maintained and disinfected. With such contaminated water aerosols potentially coming into contact with the general public, they could possibly cause serious health issues such as Legionellosis infection.


Registration and Lab Test Result Submissions

The National Environment Agency (NEA) regulates the quality of water in all cooling towers, which will be required to be registered, under the Environmental Public Health (Registrable Aerosol-generating Systems) Regulations 2021 [PDF, 113.2 KB]. The definition of cooling tower can be found in the Environmental Public Health (Registrable Aerosol-generating Systems) Order 2021 [PDF, 81.23 KB]. 

Upon successful registration, owners/occupiers will be required to ensure that the water quality of their AGS complies with the regulatory limits stipulated in the Regulations by arranging for the AGS water to be tested in a testing laboratory accredited by the Singapore Accreditation Council (SAC) and submitting water quality test results to NEA at the frequency stipulated in the Regulations.

The registration and the submission of water quality test results can be submitted electronically via NEA ePortal. Step-by-step user guides can be found as follow:

  1. Step-by-step User Guide on Registration [PDF, 557 KB]
  2. Step-by-step User Guide on Lab Test Result Submission [PDF, 313 KB]

The standard excel template for AGS lab test result bulk upload submission can be found as follow:

  1. Standard excel template for lab test results bulk upload submission [XLSX, 13 KB]

More information can also be found in the Circular and FAQs on Registration of Cooling Towers as Aerosol-generating Systems [PDF, 253 KB].

Code of Practice on Environmental Health (COPEH) 2021

The minimum design criteria for siting of cooling towers at building plan submission, can be found in section 4 of Code of Practice on Environmental Health (COPEH) 2021 [PDF, 699.1 KB].