supply and refilling of hydrogen gas cylinders for htps supply and refilling of hydrogen gas cylinders for generator cooling system for htps, kasimpur , supply & refilling of hydrogen gas cylinders as per is: 1950-65 grade-i and purity 99.90% with latest amendment thereof and as per following composition: 1) water: mg/m3 = 10 maximum 2) oxygen: % by volume = 0.0010 maximum 3) co2: % ppp volume = 10 maximum 4) hydrogen: % by volume = 99.90 minimum note: hydrogen gas will be filled in compressed condition at approx. 155-160 kg/cm2 pressure and temperature 15 degree c to be filled in empty department cylinders. capacity of cylinders: 7 cubic meters.