16- 219 C.M.R. ch. 4, § 3
3-1 General Provisions
3-1.1 Every automatic sprinkler system shall have at least one automatic water supply.
3-2 Water Supply Sources
3-2.1 The following water supply sources are acceptable:
3-2.1.1 A connection to a reliable water-works system.
3-2.1.2 An elevated tank.
3-2.1.3 A pressure tank installed in accordance with NFPA #13, Standard for the Installation of Sprinkler Systems, and NFPA #22, Standard for Water Tanks for Private Fire Protection.
3-2.1.4 A stored water source with an automatically operated pump on a dedicated circuit of proper size and capacity, Pumps shall not cycle on and off during minimum flow situations, i.e., one sprinkler flowing.
3-2.2 All stored water sources shall have an automatic filling mechanism set to regulate the available water supply volume from a minimum low water level equal to 110% of the calculated volume to a minimum high water level of 125% of the calculated volume, or, an audible water level alarm set to give a steady signal when the water level falls below 125% of the calculated volume. Tanks shall be covered and protected against freezing. When stored water is used as the sole source of supply, the minimum calculated volume shall equal the water required to flow 3 sprinklers for 10 minutes (see 5-1,3)
3-3 Combined Piping System
3-3.1 A piping system serving both sprinkler and domestic needs shall be acceptable when:
3-3.1.1 A demand flow of 5 gal/min is included for domestic use. The domestic use shall be added to the sprinkler system in determining the size of common piping and the size of the total water supply requirement. In multiple occupancies, 2.5 GPM for each living unit up to a maximum of 50 GPM shall be added to the calculated system demand.
3-3-1.2 All piping in the system conforms to the piping specifications of this standard.
3-3.1.3 Permitted by the local plumbing or health authority.
3-4 Water Utility
3-4.1 Every Life-Safety Sprinkler System supplied by a water utility shall be provided with the following:
3-4.1.1 A State Department of Human Services approved and local utility accepted backflow prevention device arranged to prevent non-potable water from entering the domestic water supply of the distribution system. Connection for fire protection to city mains is often subject to local regulation concerning metering and backflow prevention requirements. The flow characteristics of the meter and/or backflow prevention device must be included in the hydraulic calculation of the system.
3-4.1.2 An approved pressure reducing valve in those locations where water utility pressure exceeds 120 p.s.i.
3-4.2
3-4.2.1 A service line to support a Life-Safety Sprinkler System shall be installed to the utilities specifications.
3-4.2.2 The local water utility shall comply with the local fire department requirements concerning notification of the disruption of water service to properties protected by Life Safety Sprinkler Systems, The local water utility and local fire department will be notified by the State Fire Marshal's Office of any Life Safety Sprinkler System installed within their jurisdictions
16- 219 C.M.R. ch. 4, § 3