Standard for Installation of Fire Safety Devices based on Use and Occupancy Article 21

Automatic alarm equipments for gas leakage shall be equipped in the following places where gas is used:1.Underground storeys used for the purposes listed in 12.1 where the total floor area amounts to 1,000m2 or more.2.Underground storeys used for the purposes listed in 12.5 (1) where the total floor area amounts to 1,000m2 or more, among which the total floor area of Class A places accounts for 500m2 or more.3.Underground buildings with a total floor area not less than 1,000 m2.