The usual way to keep tires at the correct pressure is to inflate them with air, but it is becoming more common to find the possibility of inflating tires with nitrogen. There are advantages and disadvantages to using one gas or another. We analyze them in depth:
Nitrogen characteristics
Nitrogen (N2) may sound like a fertilizer or something similar to you, but it is a inert gaswithout any effect on the organism, very present in the plant. So much so that the main component of the air in the atmosphere that we breathe is 78% hydrogen, while 21% is oxygen (O2) and it also has other gases in smaller proportions, such as argon, hydrogen and CO2.
One of its main characteristics is not being as flammable as oxygen (that is why a fire goes out if it does not have air). In fact, the aeronautical industry It requires the use of N2 and very low concentrations of O2 inside the tire to avoid flammability problems, in addition to the fact that oxygen is quite unstable to temperature changes: it expands in heat and contracts in cold.
Another sector that often uses nitrogen is the commercial vehicle sector. Some manufacturers specifically recommend it and for certain companies it is very easy and economical to implement nitrogen generators to have lower operating costs. But why would it be of interest to a private driver?
Benefits of inflating wheels with nitrogen
- Lower pressure losses: Nitrogen molecules are larger than oxygen molecules, which means they can escape through the pores of the tyres. Any leaks that may occur in the tyre are up to four times slower than with regular air. This helps the pressure inside the tyre to remain homogeneous for longer, and the tyres need to be inflated less often.
- Longer tire life: Since a more stable pressure is maintained regardless of the temperature, uneven tyre wear is less likely to occur. This extends the tyre’s useful life, as the tyre is prevented from expanding and compressing when the temperature inside the wheel rises, and the contact area between the tyre and the road – the tread – is not reduced (worsening the centre more) or widened (worsening the sides more). As there is less contraction and expansion, the tyres do not age prematurely, there is less risk of a blowout and greater safety.
- More fuel efficiency: A tyre with optimal pressure for a longer period of time helps to save fuel. It is estimated that underinflated tyres increase fuel consumption by between 0.5% and 3%.
- Lower risk of oxidation: Nitrogen does not react easily with other materials. Less oxygen reduces the risk of internal oxidation of rims and other metal components, prolonging their useful life.
Problems when inflating wheels with nitrogen
- Price: Nitrogen can be more expensive than compressed air, as it requires specialised equipment, so you can only inflate tyres with nitrogen at a shop that has it. However, its proponents claim that it saves money over air in the long term.
- Availability: Unlike compressed air, it is not widely available everywhere. If pressure loss occurs in nitrogen-inflated tires, it may be more difficult to find a place to re-inflate them with nitrogen. However, if you ever find that one of your tires is not at the correct pressure, you can top it up with air, which can be combined with nitrogen without any problem.
In short, if you want more stable tire pressure over the long term, less pressure loss and longer tire life, nitrogen inflation is an option worth considering, provided cost and availability are not too important factors.
