Section 18(2)(x) in The Static and Mobile Pressure Vessels (Unfired) Rules, 2016
(x)each safety relief valve for static vessel shall be provided with angle type approved safety valve with shut-off valve between it and the vessel. The arrangement of the shut-off valve installed between the safety relief valve and the vessel shall be so designed as to afford full required capacity flow through at least one of the safety relief valves. In case of cryogenic vessel the safety relief valve may be provided with multi-way flow diverter valve;