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LC Urgent Q2: Health risks posed by Legionella bacteria to the staff at Tamar

     Following is a question by Dr Hon Priscilla Leung under Rule 24(4) of the Rules of Procedure and a reply by the Secretary for Food and Health, Dr York Chow, in the Legislative Council meeting today (January 11):


     Since the Secretary for Education was found to have contracted Legionnaires' disease in December last year, the authorities have conducted sampling checks of water at various locations at the new Central Government Complex (new CGC) and the Legislative Council Complex (LegCo Complex) at Tamar, and Legionella bacteria have been found in a number of the water samples.  In less than six months since the occupation of the new CGC and LegCo Complex, such a serious bacteria breeding problem has already occurred; and there have been media reports that since the occupation of the new CGC and LegCo Complex, internal remedial works have been continuously carried out, and the pollutions caused by the dust and chemical materials generated during this period have caused the staff at the aforesaid sites to have fallen ill one after another.  In this connection, will the Government inform this Council:

(a) of the total number of water samples taken from the water taps at the new CGC and LegCo Complex by the Department of Health for testing as at this Tuesday, and among them, the number of samples confirmed to contain Legionella bacteria; whether the immediate remedial measures currently taken by the authorities are sufficient to completely eliminate the threat of the bacteria and fully care for the health of the staff at the aforesaid sites;

(b) at present remedial works are still being carried out continuously each day at the new CGC and LegCo Complex, whether this is due to the rush to move in before completion of the works, and when the remedial works are expected to be thoroughly completed; whether the authorities will immediately conduct a comprehensive risk assessment in respect of the pollutions caused by the dust and chemical materials generated during the remedial works, so as to ensure that Legionnaires' disease or other diseases will not be triggered, or serious health risks will not be posed to staff; and

(c) whether the authorities will pursue with the related persons over the responsibility of this incident; and whether they will, by learning a lesson from the incident, immediately require prior checking of water supply systems in all newly completed buildings to ensure the cleanliness before approving the occupation of the buildings?



     My reply to Dr Hon Priscilla Leung's question, with input from various Government departments incorporated, is as follows:

(a) On December 22, 28 and 29, 2011, the Centre for Health Protection (CHP) collected a total of 43 water samples before cleansing operations at the Central Government Offices (CGO), the Chief Executive's Office, the Legislative Council (LegCo) Complex and Tamar Park.  According to the final laboratory testing results, 23 water samples taken at 19 locations were found to contain bacteria exceeding standards, with the level ranging from 0.7 to 14.2 colony forming units per millilitre (cfu/ml).  Details are set out in the Annex.

     Cleansing and disinfection operations have been carried out in phases and were fully completed on January 8.  The disinfection procedures referred to the guidelines of the British Standards Institute.  The water supply system and water outlets were soaked with hyperchlorinated water for at least one hour in order to kill Legionella bacteria, then flushed with water such that chlorine levels reverted to drinking water standards recognised by the Water Supplies Department (WSD).

     Following the cleansing and disinfection operations, CHP, the Architectural Services Department (ArchSD) and the Water Supplies Department took about 400 post-cleansing water samples at CGO, the Chief Executive's Office, LegCo Complex and Tamar Park.  Laboratory testing is under way.  In addition, the Henry Fok Professor in Infectious Diseases, Department of Microbiology, the University of Hong Kong, Professor Yuen Kwok-yung, conducted testing after the cleansing and disinfection operations.  Among the 227 samples taken at showers and water taps, only 1 was found to contain a small amount of genetic fragment of Legionella bacteria.

     The Chief Secretary for Administration's preceding reply has set out in detail health measures adopted by the Administration for staff of CGO and LegCo.  This includes the setting up of health seminars and briefings, a telephone hotline and a designated help desk at Ruttonjee Hospital.  I shall not repeat here.

(b) The second part to the question is about remedial works.  The Tamar Development Project is in no way rushed.  The works contract was signed in 2008 for a period of 39 months and was completed in 2011.  As in other construction projects, it is normal for remedial works to be required after taking over the building.

     In addition, the Administration has received a number of suggestions from relevant organisations or users.  The Administration will consider these and suitably enhance the design, such as the improvement of barrier-free facilities.  These works may only be followed up one-by-one after users move in.

     As in the case of all new buildings, remedial works and adjustments are expected at the initial periods of moving in.  ArchSD will urge its contractor to complete the remedial works as soon as possible.  ArchSD has always strictly implemented quality control and will follow established procedures and standards for inspection on acceptance, to ensure that requirements are met.  It will certainly not accept works that are not in compliance with requirements or safety standards.  According to the terms of contract, the contractor shall be responsible for remedial works and follow up on sub-standard items during the warranty period.

     While remedial works are in progress, the contractor shall take appropriate measures such as portioning of the works area, the use of protective barriers, and the adoption of noise and dust barriers.  It shall also co-ordinate the timing of works to minimise impact and disruption to users' daily operations.  In fact, most of the remedial works have been arranged to take place during weekends or holidays.

     If colleagues with chronic illnesses are worried about their working environment, or if any colleagues feel unwell, they may consult medical practitioners.

(c) It has always been the Government's target for the Tamar Development Project to be completed in 2011 and to commission it in phases.  Construction and acceptance have generally been on schedule.  The procedures and standards of construction and acceptance were in strict accordance with relevant legislation, codes of practice and works-related guidelines.  The Government has been following WSD's established guidelines and conducted tests on water quality prior to commissioning the CGO building.  In fact, the World Health Organization's guidelines on drinking water do not carry requirements on testing Legionella bacteria.  WSD does not make such requirements either.

     At present, relevant departments are investigating the cause of the incident.  Professor Yuen Kwok-yung presented some of his preliminary analysis at the press conference on January 9.  He said that there has been a lapse in time between the completion and commissioning of CGO, which meant low water usage rates on certain floors.  Infrequent water flow, stagnation of water and relatively low temperatures of water heaters might cause the growth of bacteria.  ArchSD will study the investigative results from various parties and work with the Prevention of Legionnaire's Disease Committee, the University of Hong Kong and relevant departments, in order to review the design, testing and inspection of water supply systems and make relevant improvements.

Ends/Wednesday, January 11, 2012
Issued at HKT 14:26


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