An automatic sprinkler system shall be provided throughout existing buildings where cellulose nitrate film or pyroxylin plastics are manufactured, stored or handled in quantities exceeding 100 pounds (45 kg). Vaults located within buildings for the storage of raw pyroxylin shall be protected with an approved automatic sprinkler system capable of discharging 1.66 gallons per minute per square foot (68 L/min/m2) over the area of the vault.
An approved automatic sprinkler system shall be provided in the following occupancies located in basements when such areas exceed 2,500 square feet (232.3 m2) in size and do not have 20 square feet (1.86 m2) of opening entirely above the adjoining ground level in each 50 lineal feet (15 240 mm) or fraction thereof of exterior wall on at least one side of the building:
- Group A occupancies used as commercial drinking and dining establishments.
- Group A occupancies used as bowling alleys.
- Group E occupancies used for student occupancy.
- Group I occupancies.
- Group R-1 and R-2 occupancies having dwelling units or guest rooms.
Openings required by this section shall have a minimum dimension of 30 inches (762 mm).