LPG means liquefied petroleum gas which is mixture of n Butane and n-pentane used in household & industrial application. The earlier tube (green colour) was used extensively in the above application . However the tube did have a few drawbacks like, not being rodent proof, had a low bursting pressure. To overcome the above drawbacks and to make the tube absolutely safe for domestic use, the specification was revised as per BIS Std (13 9573, Type IV) which has the following parameters