Hong Kong – Public should take precautionary measures against carbon monoxide poisoning

     Following a notification from Yan Chai Hospital (YCH) on a cluster of carbon monoxide poisoning, the Centre for Health Protection (CHP) of the Department of Health and the Electrical and Mechanical Services Department (EMSD) today (November 24) appealed to members of the public to take precautionary measures against carbon monoxide poisoning.
 
     The cluster involved two males and one female, aged between 13 and 56, who are family members living together. The 56-year-old male was found unconscious after having shower yesterday (November 23). He was immediately sent to YCH and was later transferred to Pamela Youde Nethersole Eastern Hospital for treatment. The other two persons, who were exposed to carbon monoxide, were also sent to YCH for examination. They are in stable condition. Two of the patients have been discharged.
 
     A preliminary investigation revealed that all of them were diagnosed with carbon monoxide poisoning. When the 56-year-old patient took the shower, all the windows in the flat were closed and the exhaust fan was not turned on.
 
     A site investigation by the EMSD discovered that the subject gas water heater is of a flueless type and should not be used in bathrooms. The model concerned has not been approved by the EMSD and did not bear a “GU” mark. It is preliminarily suspected that the exhaust flue gas generated by the gas water heater without flue was discharged into the bathroom, coupled with poor ventilation, carbon monoxide accumulated due to insufficient oxygen for combustion and thus led to the carbon monoxide poisoning. The EMSD has seized the subject gas water heater and will investigate whether any person has contravened the Gas Safety Ordinance.
 
     The CHP said that carbon monoxide is a colourless, odourless and tasteless gas which is a by-product from incomplete combustion of any fuel which contains carbon, such as wood, natural gas and gasoline.
 
     Exposure to a low concentration of carbon monoxide can lead to a range of symptoms such as dizziness, headache, tiredness and nausea; whereas exposure to a high concentration of carbon monoxide can lead to impaired vision, disturbed co-ordination, unconsciousness, brain damage or even death.
 
     The CHP reminded members of the public that a gas water heater should be used in a well-ventilated area. They should seek medical attention immediately if suspected of developing symptoms of carbon monoxide poisoning.
 
     The EMSD also reminds members of the public of the following:

1. Occupants should buy and use gas water heater which has been approved by the EMSD and bears a “GU” mark;  
2. All installations, replacements or repair work on gas water heaters must be carried out by a registered gas installer employed by a registered gas contractor;
3. Gas appliances including gas water heaters and gas cookers should be used in well-ventilated areas, helped by switching on extraction fans and not closing all windows and doors; and
4. Occupants should arrange regular safety inspection of gas water heater every 18 months by a registered gas contractor. If the condition of the gas water heater is in doubt, please stop using it immediately and contact the registered gas supply company.