Zero AIR 5.0 (99.999%) ( CO+CO2 1ppm, H2O 3ppm, THC 0.2 ppm) can be an ideal zero gas for analytical instrumentation especially when components of interest are being measured or detected at ppm and percentage levels. It is also an ideal detector and/or purge gas for a wide variety of detector types, analytical techniques and processes. Supplied in a 50 litre steel cylinder containing 200 bar.