Filling tyres with nitrogen

The air we breath (and the normal compressed air used to inflate tyres) contains 78% Nitrogen, 21% Oxygen and 1% other gases. Purified nitrogen has been used to inflate tyres on aircraft and racing cars for many years, but now Tony Blundell Tyre specialists will soon be offering nitrogen inflation for ordinary car and van tyres.

For passenger car applications the main claims seem to be

 Leakage can occur through the tyre's inner liner but can also occur through the valve, punctures, or failure of the seal between tyre and wheel rim. Pure nitrogen might leak more slowly through the liner, but regular checks of tyre condition and pressures will still be essential.  Changing to nitrogen involves removing all the air which is already in the tyres and then re-inflating them with purified compressed nitrogen.