Section 27(2) in The Static and Mobile Pressure Vessels (Unfired) Rules, 2016
(2)Compressors-(i)the design, material and construction of compressors shall be suitable for the type of gas which they are to handle and they shall be designed for the maximum outlet pressure to which they will be subjected to in operation;(ii)compressors other than multi-stage compressors shall take suction from the vapour space of the vessels being filled.
