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Guilherme Mazui

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What is the Difference Between Nitrox and Air?

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The main difference between nitrox and air lies in their oxygen and nitrogen content. Nitrox is a breathing gas that contains more oxygen and less nitrogen than standard air, typically containing anywhere from 28% to 36% oxygen and 64% to 72% nitrogen. In contrast, standard air consists of approximately 21% oxygen and 79% nitrogen.

Diving with nitrox offers several benefits:

  1. Less nitrogen absorption: Since nitrox has a lower nitrogen content, your body absorbs less nitrogen during a dive. This reduces the risk of decompression sickness (DCS) and allows you to spend more time underwater.
  2. Shorter surface intervals: Nitrox enables you to off-gas (eliminate absorbed nitrogen) more quickly during surface intervals, allowing you to return to diving sooner than if you were using standard air.
  3. Longer dives at shallower depths: Nitrox allows you to stay at depth longer than someone diving with air, assuming equal gas consumption. However, it does not extend dive time at greater depths because of the increased oxygen content's toxicity risk.
  4. Less fatigue: Divers have reported feeling less tired after diving on nitrox, although this is not scientifically proven.

Keep in mind that diving with nitrox requires proper instruction and certification, as it is not suitable for all dive profiles and requires a dedicated nitrox tank.

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  • What is the Difference Between Nitrox and Air?
  • Comparative Table: Nitrox vs Air

    • Comparative Table: Nitrox vs Air

    Here is a table comparing the differences between nitrox and air:

    Aspect Nitrox Air
    Definition A breathing gas made up of any combination of oxygen and nitrogen, with more than 21% oxygen. A breathing gas made up of approximately 21% oxygen and 78% nitrogen.
    Oxygen Partial Pressure At a given depth, nitrox has a higher oxygen partial pressure than air. At a given depth, air has a lower oxygen partial pressure than nitrox.
    Nitrogen Absorption Nitrox reduces the percentage of nitrogen in the breathing gas, leading to less nitrogen absorption in the blood. Air has a higher nitrogen content, leading to more nitrogen absorption in the blood.
    Decompression Sickness Reduced nitrogen absorption with nitrox results in a lower chance of decompression sickness (DCS). Increased nitrogen absorption with air results in a higher chance of decompression sickness (DCS).
    Dive Time Nitrox allows for extended bottom time due to reduced nitrogen absorption. Air has a shorter bottom time due to increased nitrogen absorption.
    Surface Interval Nitrox requires a shorter surface interval between dives compared to air. Air requires a longer surface interval between dives compared to nitrox.

    In summary, nitrox is a breathing gas with more oxygen and less nitrogen than air, which results in reduced nitrogen absorption, a lower chance of decompression sickness, extended bottom time, and shorter surface intervals between dives.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.