Section 61(1)(a) in The West Bengal Factories Rules, 1958
(a)all process [storages, equipments, plants, etc.,] [Inserted by W. B. Factories Amendment Rules, 1991, dated 27.11.1991.] involving serious explosion and flash-fire hazards shall be located in segregated buildings where the equipment shall be so arranged that only a minimum number of employees are exposed to such hazards at any one time;