According to the Gas Safety Ordinance, from 1 January 2003, all models of domestic gas appliances to be supplied and sold for use in Hong Kong shall have the written approval of the Gas Authority (i.e. the Director of Electrical and Mechanical Services). Approved domestic gas appliances shall bear a GU mark as identification. For safety sake, members of public and restaurants should only purchase domestic gas appliances with the GU mark and consider to replace the domestic gas appliances installed before the legislation relating to the GU mark came into force.
Relevant information under the Mandatory Energy Efficiency Labelling Scheme (MEELS) (Gas Cookers and Gas Instantaneous Water Heaters) is available in the following EMSD website.