103.1 Separate fire and domestic services shall be provided for any building, except as follows:

1. (a) An entirely metered service may be used for both domestic and fire service;
2. (b) A combined service with meter on the domestic branch only may be used where the fire service branch is used solely for supply of a closed circuit sprinkler system controlled by alarm valves or supervisory service; or
3. (c) A combined service with a standard meter on the domestic branch and a detector check of a type approved by the American Insurance Association (AIA) on the fire service branch may be used where the fire service branch supplies any open sprinkler system, standpipes, hose connection outlets, external fire hydrant, or other outlets.

103.2 Under §§103.1(b) and 103.1(c), if a combined service with domestic branch not exceeding two inches (2 in.) in diameter is to be installed, the domestic branch shall be supplied by means of a corporation cock inserted in the main line of the combined service by the Department at the expense of the applicant.

103.3 In all cases involving metering of branches of combined services, the meters shall be installed as close as practicable to the point of branching.

103.4 Curb-cocks and boxes shall be prohibited.

SOURCE: 12 DCRR §401.4 (October 1981).