Section 16 in The Static and Mobile Pressure Vessels (Unfired) Rules, 2016
16. Filling capacity and filling pressure.
(1)The Maximum quantity of liquefiable gas filled into any vessel shall be limited to the filling density of the gas and shall be such that the vessel shall not be liquid-full due to expansion of the contents with rise of the temperature to 550 C. If vessel is un-insulated, or to the highest temperature which the contents are likely to reach in service. If the vessel is refrigerated or insulated, this requirement shall be applicable irrespective of the ambient temperature of the product at the time of filling.(2)No vessel shall be filled with any permanent gas in excess of its design pressure.(3)The water capacity of the cryogenic pressure vessel shall be rated in terms of gross water capacity and the allowable water capacity in litres at 15°C. The usable water capacity shall not exceed 95% of the gross water capacity. An overflow pipe shall be provided at the maximum allowable capacity level as a safeguard against filling the vessel beyond the maximum usable capacity.
