Difference Between Nitrox and Air

The key difference between nitrox and air is that nitrox is a mixture of mainly nitrogen and oxygen gas, whereas air is a mixture of many components, including nitrogen, oxygen, water vapour, etc.

Atmospheric air is a form of nitrox because both air and nitrox are mixtures of nitrogen and oxygen gases.

1. Overview and Key Difference
2. What is Nitrox
3. What is Air
4. Side by Side Comparison – Nitrox vs Air in Tabular Form
5. Summary

What is Nitrox?

Nitrox is a term used to name any mixture of gases containing nitrogen and oxygen with trace amounts of other gases. Therefore, atmospheric air is also a type of nitrox that consists of 78% of nitrogen gas and 21% of oxygen gas plus 1% other gases, primarily including argon. However, in specific applications such as underwater diving occasions, nitrox is used to be distinguished from normal atmospheric air, and it is also handled differently. Moreover, in applications such as scuba diving, nitrox is used with a higher proportion of oxygen gas in the gas mixture. This is because the reduced partial pressure of nitrogen in the nitrox gas mixture can be advantageous in reducing the nitrogen uptake by body tissues. The capability of underwater dive time is also increased through the reduction of the decompression requirement.

There are two major recreational diving nitrox mixtures containing 32% and 36% oxygen, which has maximum operating depths of 34 meters and 29 meters, respectively. Moreover, a nitrox mixture containing 40% of oxygen is uncommon with recreational diving. This is because all pieces of diving equipment that come into contact with mixes consisting of high proportions of oxygen (mainly at high pressures) requires special cleaning and servicing in order to reduce the risk of fire. Moreover, the rich mixers can extend the time a diver can stay underwater without requiring any decompression stops.

What is Air?

Air is the substance that makes up the Earth’s atmosphere. There are five main gases that form the atmospheric air: nitrogen gas, oxygen gas, water vapour, argon gas and carbon dioxide. There can be some other components as well. These gases are present in the air in different proportions. Nitrogen gas composition is about 78%, oxygen gas is about 21%, argon is about 0.9%, etc. However, the composition of air can vary with altitude. The air that is important for breathing, photosynthesis and other life requirements can be found at lower levels of the atmosphere, closer to the Earth’s surface where living organisms exist rapidly.

The gases in Earth’s atmosphere protects life on Earth by creating pressure which allows the existence of liquid water on Earth’s surface. Moreover, the air is helpful in absorbing UV radiation which warms up the Earth’s surface through heat retention. Moreover, the air is important in reducing temperature extremes between night and the daytime.

What is the Difference Between Nitrox and Air?

Nitrox is a term used to refer to any mixture of gases containing nitrogen and oxygen with trace amounts of other gases, while air is the substance that makes up the Earth’s atmosphere. The key difference between nitrox and air is that nitrox is a mixture of mainly nitrogen and oxygen gas, whereas air is a mixture of many components, including nitrogen, oxygen, water vapour, etc.

The following is a summary of the difference between nitrox and air in tabular form.

Summary – Nitrox vs Air

Nitrox is a term used to name any mixture of gases containing nitrogen and oxygen with trace amounts of other gases. Air is the substance that makes up the Earth’s atmosphere. The key difference between nitrox and air is that nitrox is a mixture of mainly nitrogen and oxygen gas, whereas air is a mixture of many components, including nitrogen, oxygen, water vapour, etc.

Reference:

1. Helmenstine, Anne Marie. “The Chemical Composition of Air.” ThoughtCo, Oct. 29, 2020, Available here.

Image Courtesy:

1. “Decompression Dive-Preparation” By DiverDave at English Wikipedia (CC BY 3.0) via Commons Wikimedia
2. “Atmosphere gas proportions” By Mysid – Vectorized version of w:Image: Atmosphere gas proportions.gif (originally by Brockert) (Public Domain) via Commons Wikimedia