procurement of da o2 n2 and co2 gas under gs group for the year 2022 23 procurement of da o2 n2 and co2 gas under gs group for the year 2022 23 , oxygen gas as per is 309/2005 (4th rev.) purity of compressed oxygen gas should be minimum 99% by volume. the gas shall be free from moisture and its due point should be minimum 0 °c, to be filled in7m3 empty cylinders of ggsstp. (102 nos. cylinders each cylinder of 7m3capacity ) ±5% variation , dissolved acetylene gas (d.a. gas) for industrial use as per is-308/1988 (3rd rev.) with amendment 1 in cylinders. the gas shall be free from moisture and its due point should be minimum 0 °c to be filled in 7m3 empty cylinders of ggsstp. (220 nos. cylinders each cylinder of 7m3 capacity ) ±5% variation , carbon dioxide gas (co2) is: 307/1966 (grade2) to be filled in ggsstp empty cylinders of capacity 3/6/18/22 kg as per ggsstp requirement. (±5% quantity variation) , nitrogen gas ‘a’ grade 99.9% pure in cylinders of 6.6 m3 at 130-140 kg/cm2pressure be free from moisture and its dew point should be minimum (-) 50°c. (11nos cylinders each cylinder of 6.6 m3 capacity) ( ±5% variation)