Nitrogen Vs Compressed Air

Nitrogen or Regular Compressed Air? If you’re confused about which one to use in your tyres, don’t panic – you’re not alone.

nitrogen vs air

Nitrogen does have some scientific advantages over Compressed Air but its arguable whether an average driver will reap any benefits from using nitrogen.

Factors to help decide whether to go for Nitrogen or Compressed Air

1. Cost and convenience ADVANTAGE FOR.COMPRESSED AIR.

Ordinary compressed air is readily available at no cost in most service stations or tyre dealers at very minimal cost. Not so with nitrogen. Nitrogen must be 93-95% pure to be effective.

If your nitrogen-filled tyres are deflated on the road where nitrogen is not available, you can top up the tyre with air with no ill effects to the tyre or your vehicle’s handling. However, you may have to refill the tyre with nitrogen later to purge the air.

2.Maintaining tyre pressure over a period of time:  A SMALL ADVANTAGE FOR NITROGEN.

All tyres have microscopic pores through which any inflating gas, air and nitrogen included, will seep out over an extended period of time, gradually lowering the inflation pressure. Nitrogen has larger molecules than air and will move through the tyre more slowly than air, thus maintaining pressure for longer periods.

However, use of nitrogen in tyres is not a substitute for regular tyre pressure checks.

3. Fuel economy: TIE.

 A drop in tyre pressure increases the rolling resistance of your tyres, which is what causes the decrease in your fuel mileage. Studies have found out that using nitrogen to inflate tyres does not change a tyre’s rolling resistance – therefore nitrogen won’t have an effect on your fuel economy. As always, check your tyre pressure at least once a month and keep your tyres at the recommended inflation pressure to minimize rolling resistance and maximize your fuel mileage.

4. Long-term tyre aging and wheel corrosion: ADVANTAGE FOR NITROGEN.

Air is 78% nitrogen and 21% oxygen, with the remainder being trace gases. Oxygen can retain moisture inside your tyres and eventually can oxidize the internal tyre wall casing, causing premature tyre aging. In extreme cases, the moisture can even cause the tyre’s steel reinforcing belts to rust. If the wheel’s paint protection is damaged, this can also promote rust in rims, resultantly they will start to lose pressure until the rim is cleaned and painted.

Nitrogen, on the other hand, is an inert, dry gas and does not support moisture. The use of 93-95% pure nitrogen will prevent premature tyre aging and wheel corrosion due to internal moisture. However, some experts say that under normal driving conditions, a tyre’s tread will reach its minimum usable depth long before any effect of oxidation on the tyre wall or wheel rust. Although nitrogen has the technological advantage here, the practical benefit is minimal under normal driving conditions. It may be beneficial if your car is not driven regularly or is placed in storage.

5. Race car, airplane and heavy equipment tyres: ADVANTAGE FOR NITROGEN.

Almost every race car, airplane, and heavy equipment tyre is filled with nitrogen. These vehicles subject tyres to extreme temperature conditions, and the use of nitrogen allows better control over tyre pressure as tyre temperature increases. Compressed air holds moisture and the amount of moisture may vary from tyre to tyre. During extreme usage, the amount of moisture in the tyre causes the tyre temperature to increase more rapidly, and in a non-linear way that can be unpredictable. With dry nitrogen, the effects of moisture are eliminated and the increase in tyre pressure due to temperature is more linear and predictable than with air. The tyres also run cooler, which is especially important in racing because the grip of race tyres is highly dependent on tyre temperature.

Your choice on Nitrogen and Compressed Air depends on how you use your vehicle

In conclusion, nitrogen does have some technological advantages over compressed air for tyre inflation. Whether or not those advantages will be of any practical use to you depends on how you use your car. Certainly, if you fall into one or more of the categories below, using nitrogen could be beneficial:

  • If you have one or more cars that are primarily used at the racetrack
  • If you drive very sparingly and your car sits unused for an extended time
  • If you own collectible cars that are seldom driven any great distances
  • If you have to put your car in storage for a significant period of time

Overall, there is not harm in filling your tyres with nitrogen if you’re interested, you can test it out. If you don’t like it or don’t see any benefits, you can always go back to the free (or almost free) compressed air we’ve all used successfully for years.