Chapter 8- Provisions for High Rise Development Section-8.5 Building services Section-8.5.5 Transformers

This section outlines the general requirements for transformers:
a. If transformers are housed in the building below the ground level it shall be
necessarily in the first basement in separate fire resistance room of four hours rating.
Transformer shall be dry type and shall be walls doors cut-out having fire resistance rating of four hour. The room shall necessarily be at the periphery of the basement having separate and direct access from open area at ground floor through a fire escape staircase. The entrance to the room shall be provided with a steel door of two hours fire rating. A curb of a suitable height shall be provided at the entrance in order to prevent the flow of oil from ruptured transformer into other parts of the basement. The switchgears shall be housed in a separate room separated from the transformer bays by a fire-resisting wall with fire resistance not less than four hours.
b. The transformer shall be protected by an automatic high-pressure water spray or a foam sprinkler system. When housed at ground floor level it/they shall be cut-off from the other portion of premises by Fire Resisting Walls of four hours fire
resistance. They shall not be housed on upper floors.
c. A tank of RCC construction of adequate capacity shall be provided at lower basement level, to collect the oil from the catch pit in case of emergency. The pipe connecting the catch-pit to the tank shall be of non-combustible construction and shall be provided with a flame-arrester.