Product information

For nitrogen the following is valid:

  • 1 nm3 = 1.147 kg
  • 1 kg = 0.872 nm3
  • 1 bar = 14.5 psi
  • 1 nm3 = 35.3 ft3
  • 1 kg = 2.2 lbs

The gas capacity of a cylinder can calculated in two different ways. The most simple method is the water capacity of the cylinder (in litres) multipled by the actual pressure (in bar); the result is the capacity in litres. Although a simple method it is not the most accurate method. A better but much more complex method will give a more accurate value for the gas capacity; it will take the compressability of the gas at both 1 bar and at the actual pressure in consideration and all based on 15 degrees C. The result is often quoted as normal litres or normal cubic metres (nm3). For nitrogen the more accurate method will give a slightly higher value as compared to the simple method i.e. (10.2 m3 versus 10 nm3).


  • Nitrogen is a colourless, odourless and tasteless
  • Non-combustible and non-toxic
  • Slightly lighter than air and it's an inert gas
  • Nitrogen is well suited for purging or flushing cargo tanks and pipelines of residual gases and vapours prior to loading cargo or doing maintenance
  • It is also used as a 'blanket' on top of several types of cargoes to prevent reactions with oxygen from atmospheric air.
  • The filling pressure is lower in some locations than the normal 200 bar due to local rules and regulations that limit filling pressure.
  • Nitrogen 3.0 means > 99.9% pure and the impurities: Water (H2O) < 1000 ppm and Oxygen (O2) < 1000 ppm.


  • Perfectly suited for purging, inerting / blanketing
  • For your safety, the product is delivered in a Unitor exchange cylinder complete with barcode and unique cylinder serial number
  • We trace and track all cylinders using our system to give you peace of mind
  • We offer global availability through our Global Exchange Programme.