Section 13 in The Static And Mobile Pressure Vessels (Unfired) Rules, 1981
13. Design pressure .-The design pressure of a vessel shall not be less than-
(a)the vapour pressure of the gas in the vessel at 550C, if the vessel is meant for the storage of liquefiable gases:-Provided that if the vessel is insulated, the vapour pressure of the gas in the vessel shall correspond to the maximum temperature that is likely to be attained by the gas in the vessel;(b)the developed pressure of the gas in the vessel at 550C, if the vessel is meant for the storage of a permanent gas.(c)[ the maximum allowable service pressure with additional allowances for vacuum and static head or surge due to acceleration or deceleration, as the case may be, in respect of the cryogenic liquid proposed to be stored or transported.]
