Nitrogen has been seen as a better alternative to oxygen in Car tyres. Thus, people tend to go towards nitrogen-based tyres as well as fill-up of the same.
Some of the Pros and Cons of Nitrogen air for car tyres
Inflating a tire with Nitrogen instead of air (which is about 78% Nitrogen anyway) attempts to minimise at least four undesirable phenomena (these are the benefits of nitrogen gas):
- A gradual loss of pressure due to seepage from the tire’s (microscopic) pores: Nitrogen molecules are larger than the molecules of the other constituents of air, so they seep out at a slower rate and a tire inflated with pure (or a higher than air concentration of) Nitrogen will stay near the target pressure longer.
- Variation of pressure as a function of the temperature of the tire: Nitrogen does not expand as much as the other constituents of air when it is heated up.
- Displacement of Oxygen and Water Vapor inside the tire: The inside of the tire will be “drier” and will corrode slower because of the lower oxygen concentration.
- Oxidation is blocked. Oxygen causes oxidation. Oxidation can make rubber brittle, increasing the chance of a blow-out. Nitrogen in the tire blocks the oxidation of the internal rubber
The disadvantages of filling nitrogen in tyres mostly relate to the difficulty in procuring and handling the gas:
- There are currently no feasible devices to generate the small quantity of Nitrogen a home-user would need to inflate car tyres
- Nitrogen gas for tyres is commercially stored in heavy cylinders at between 3000 and 6000 PSI
- Nitrogen is expensive. There is a suitable reason why the FAA requires nitrogen in commercial aeroplanes, and the United States military uses nitrogen. Weight is a factor and the weight of these commercial-sized vehicles benefit from nitrogen. The claim that a passenger vehicle needs the added expense might not be as founded. Nitrogen-filled tyres usually cost about $5 or more per tire
- Releasing a large quantity of Nitrogen in a confined space will cause the percentage of Oxygen in that space to be reduced, and sufficiently large concentrations of Nitrogen will lead to asphyxiation.
Personally, I have found that while inflating my vehicle’s tyres with pure(ish) Nitrogen does keep them at the target pressure longer and that the pressure varies less with operating temperature than when I inflate with regular air, the difference is marginal. I was able to monitor this because most of my vehicles are fitted with a Tire Pressure Monitoring System (TPMS) that gives me instant read-outs of both temperature and pressure for each tire.
Conclusion
Prefer Nitrogen gas for tyres when it is easily available at low to no cost (many tire shops will inflate your tyres with Nitrogen free of cost when you pay for other services with them), but in a pinch, it is better to have your tyres at the correct pressures, inflated with regular air, rather than letting them run underinflated till you can get to a shop that provides Nitrogen for inflation.
