Latest sampling results for Legionella bacteria at fresh water cooling towers announced

     The Electrical and Mechanical Services Department (EMSD) today (May 8) announced the latest statistics for Legionella bacteria following sampling tests at selected fresh water cooling towers.

     In April, the EMSD tested 31 water samples collected from cooling towers in 20 buildings. The Legionella bacteria count (LBC) in all tested samples was below the upper threshold, which is 1,000 colony forming units per millilitre.

     From January to April 2012 the EMSD tested 302 water samples collected from fresh water cooling towers in 264 buildings. Two samples were found with an LBC equal to or above the upper threshold, leading to the issuance of nuisance notices by the EMSD under the Public Health and Municipal Services Ordinance. The required disinfection work was subsequently completed in these two cases.

     The EMSD publishes on its website ( on a half-monthly basis the latest Legionella bacteria statistics following sampling tests at fresh water cooling towers. Also listed are any buildings where the LBC was found in the fresh water cooling tower to be equal to or above the upper threshold during the preceding three-month period, and which were thus served with nuisance notices.

     A department spokesman said, "Fresh water cooling tower owners have the responsibility to design, operate and maintain cooling towers properly. They should arrange regular inspections, timely maintenance and periodic testing of the water quality of their cooling towers in accordance with the Code of Practice for Water-cooled Air Conditioning Systems issued by the EMSD in order to prevent the proliferation of Legionella bacteria."

Ends/Tuesday, May 8, 2012
Issued at HKT 14:31