Section 40(2) in The Merchant Shipping (Fire Appliances) Rules, 1969
(2)The piping shall be so arranged as to distribute the smothering gas or steam in an effective manner. In holds over 20 metres in length at least two pipes shall be provided in cargo space one at each end of the hold, i.e., one on the forward side and the other on the after part. Except in tankers and ships used for the conveyance of coal, pipes for conveying steam shall be fitted with Outlets as low as practicable in the space which they serve and as nearly as possible to the centre line of the space.
