### Gas Safety (Installation and Use) Regulations 《氣體安全(裝置及使用)規例》

22. Large consumers
Where a service pipe which has an internal diameter of not less than 50 millimetres supplies gas to—
(a) not less than 2 floors in non-domestic premises; or
(b) a floor in non-domestic premises (and irrespective of whether such premises have more than one floor) having areas with a separate supply of gas,
no person shall install an incoming installation pipe to any of those floors or areas, as the case may be, unless—
(i) an isolation valve is installed in such pipe in a conspicuous and readily accessible position; and
(ii) a line diagram in permanent form is attached to such premises in a readily accessible position as near, so far as is practicable, to the primary meters indicating the position of all installation pipes of internal diameter of 25 millimetres or more, gas meters, emergency controls, isolation valves, pressure test points, condensate receivers and electrical cross-bonding of the gas supply systems in such premises.

### Gas Safety (Installation and Use) Regulations 《氣體安全(裝置及使用)規例》

23. Gas appliances—safety precautions
(1) No person shall install a gas appliance unless—
(a) such appliance and the gas fittings and other works for the supply of gas to be used in connection with it;
(b) the means of removal of the products of combustion from such appliance;
(c) the availability of sufficient permanent supply of air for such appliance for proper combustion;
(d) the means of ventilation to the room or internal space in which such appliance is installed; and
(e) the general conditions of installation, including the stability of such appliance and its connection to any gas fitting,
are such as to ensure, so far as is reasonably practicable, that such appliance can be used without constituting a danger to any person or property.
(2) No person shall connect a domestic gas appliance which has a flue to a piped gas supply system except by a permanently fixed rigid pipe.
(3) No person carrying out the installation of a gas appliance shall leave it connected to a supply of gas unless such appliance can be used safely.
(4) No person shall install a gas appliance without there being at the inlet to it means of shutting off the supply of gas to such appliance unless the provision of such means is not reasonably practicable.
(5) No person shall carry out work in relation to a gas appliance which bears an indication that it conforms to a type approved by any person as complying with safety standards in such a manner that such appliance ceases to comply with such standards.
(6) No person carrying out work in relation to a gas appliance which bears an indication referred to in subregulation (5) shall remove or deface the indication.
(7) Where a person services a domestic gas appliance, he shall immediately thereafter examine—
(a) the effectiveness of any flue;
(b) the supply of combustion air;
(c) its operating pressure; and
(d) its safe functioning,
and forthwith notify the responsible person for the premises in which such appliance is installed of any defect.

23A. Installation of domestic gas appliance
(1) Subject to subregulation (2), no person shall install a domestic gas appliance which burns gas to provide lighting, heating or cooling unless the appliance complies with regulation 3B(1)(d) of the Gas Safety (Miscellaneous) Regulations (Cap. 51 sub. leg. F).
(2) Subregulation (1) does not apply to the reinstallation of a domestic gas appliance which has been installed in any premises before 1 January 2003.
(L.N. 43 of 2002)

### Gas Safety (Installation and Use) Regulations 《氣體安全(裝置及使用)規例》

24. Flues
(1) No person shall install a gas appliance to a flue unless the flue is so constructed and in such a condition that such appliance can operate safely with it.
(2) No person shall install a flue pipe so that it enters a brick or masonry chimney in such a way that the seal between such pipe and chimney cannot be inspected.
(3) No person shall connect a gas appliance to a flue which is surrounded by an enclosure unless the enclosure is so sealed that any spillage of products of combustion cannot pass from the enclosure to any room or internal space other than the room or internal space in which such appliance is installed.
(4) No person shall install a power-operated fan for a flue unless means are provided to safely prevent the operation of the gas appliance for which the flue is provided if such fan fails.

25. Access
No person shall install a gas appliance except in such a manner that it is readily accessible for operation, inspection and maintenance.

26. Manufacturer’s instructions
A person who installs a gas appliance shall leave with the responsible person for the premises in which such appliance is installed all operating instructions and instructions covering maintenance requirements provided by the manufacturer of such appliance.

27. Room-sealed gas water heaters
(1) Subject to subregulation (3), where suitable provision has been made for the installation of a room-sealed gas water heater to serve a bathroom in any premises, irrespective of whether such provision is made in the bathroom or in any other part of the premises, no person shall install a gas water heater in the premises to serve that bathroom unless the heater is a room-sealed gas water heater.
(2) Where suitable provision has been made for the installation of a room-sealed gas water heater to serve a bathroom in any premises, irrespective of whether such provision is made in the bathroom or in any other part of the premises, no person shall install a room-sealed gas water heater in the premises to serve that bathroom except by using that suitable provision.
(3) With effect on and from 1 January 1994, no person shall install a gas water heater other than a room-sealed gas water heater in any bathroom in any premises except that an open-flued (fanned draught) gas water heater may be installed to replace an open-flued (fanned draught) gas water heater which—
(a) is in a bathroom in any premises; and
(b) was installed—
(i) before that date; or
(ii) on or after that date in pursuance of this regulation.
(4) For the purposes of this regulation, room-sealed gas water heater (密封式氣體熱水爐) and suitable provision (適當設施) shall have the meanings respectively assigned to them by regulation 35A(4) of the Building (Planning) Regulations (Cap. 123 sub. leg. F).