Section 0(3)(3) in Petroleum and Natural Gas Regulatory Board (Technical Standards and Specifications including Safety Standards for LPG Storage, Handling and Bottling Facilities) Regulations, 2019
3.1.1Maximum Filling Volume. - Minimum vapour space or the maximum quantity of LPG filled in any vessel shall be limited to the filling density of LPG and shall be such that the vessel should not become liquid full due to expansion of the content with the rise in temperature to 55 deg. centigrade and such requirement shall be applicable irrespective of the ambient temperature of the product at the time of filling. (Generally, it is filled maximum up to 85% of the volume).