During their training, scuba divers learn about the various risks associated with deep water diving, ranging from equipment malfunctions to potentially fatal health conditions. One lesser-known but significant danger is “nitrogen narcosis”.

In this article, we will explore this uncommon threat and provide tips to prevent nitrogen narcosis, ensuring a safer diving experience.

What is Nitrogen Narcosis?

Nitrogen narcosis, which is also known as inert gas narcosis, the Martini effect, or raptures of the deep, occurs when divers breathe in high concentrations of nitrogen at great depths. Interestingly, this phenomenon is similar to what happens when you skydive from a height of 100 feet.

Although scuba diving often involves breathing air mixed with nitrogen, nitrogen narcosis occurs when a diver descends deeper into the water, causing an increase in the partial pressure of nitrogen. This leads to more nitrogen being absorbed into the bloodstream.

As the concentration of nitrogen in the bloodstream rises, it slows down the nervous system, increasing the likelihood of the diver experiencing intoxicating effects. These effects can significantly impair their judgment underwater, potentially leading to dangerous situations.

Risk Factors of Nitrogen Narcosis

Nitrogen narcosis is most likely to occur when a diver descends beyond approximately 100 feet. At this depth, the increased pressure can affect the gases being inhaled, primarily nitrogen and oxygen. Some divers are more susceptible to nitrogen narcosis, while others may never experience it at all.

Nitrogen narcosis is generally not harmful and rarely causes significant problems for divers. For most, the symptoms will dissipate after ascending a few feet.

However, divers should be aware of potential risks, such as confusion, which can impair decision-making. This could lead to forgetting to check no decompression limits or unintentionally distancing from a dive buddy. Remember to signal your dive buddy in case of experiencing nitrogen narcosis so he can monitor your condition.

Essential Tips to Prevent Nitrogen Narcosis

While nitrogen narcosis can sometimes be inevitable, adhering to safety tips can significantly mitigate the risks. Even if symptoms arise, they generally don’t have any lasting negative effects.

Here are 10 essential tips to prevent nitrogen narcosis:

Enroll in or Refresh Your Deep Diving Courses

As an advanced diver certification student, you might recall your instructor having you solve a puzzle or math problem both at the surface and at a depth of approximately 100 feet (30 meters).

This exercise was designed to evaluate your response time and determine if you experienced symptoms of nitrogen narcosis.

Clearly, in an underwater emergency, swift thinking and appropriate reactions are crucial for a diver. In addition to recognizing the symptoms of nitrogen narcosis, it’s essential to be cautious about your diving depth. Always take your training level into account before deciding to push a few extra meters or feet.

The encouraging news is that frequent or deeper-depth divers tend to experience less intense effects of nitrogen narcosis. However, it’s essential never to dive beyond your training or comfort level.

Limit Your Dives to Depths Less Than 30 Meters

Of course, the best approach is to avoid getting “narced” altogether. However, this doesn’t mean you should miss out on dives deeper than 60 feet. The limits of safe diving exceeds 60 feet, but it’s advisable not to exceed 98.4 feet (30 meters) where symptoms tend to become more pronounced.

Nonetheless, it is essential for divers to recognize the warning signs and continuously monitor their own mental state and that of their diving companions.

Anticipate Its Occurrence

When diving below 60 feet, it’s wise to anticipate experiencing some symptoms of nitrogen narcosis and be ready for this possibility. Familiarize yourself with all the symptoms and learn how to recognize and address them. Both novice and professional divers need to identify nitrogen narcosis symptoms to prevent any accidents or emergencies.

Ensure You’re in Good Physical Condition.

Deep diving already carries significant risks, so it’s crucial to avoid additional factors that could worsen your symptoms. Ensure you’re physically prepared by being well-rested and healthy before the dive. Remember that there are some conditions that can accelerate the onset of narcosis:

• pre-dive fatigue.
• Anxiety.
• Stress.
• Hangovers.
• Conditions like carbon dioxide retention or hypercarbia (caused by environmental factors, lung issues, or excessive rebreathing of exhaled CO2).

It’s crucial to avoid consuming alcohol or drugs before a dive, as both can intensify nitrogen narcosis effects and even trigger similar symptoms. Additionally, remember to exhale slowly.

Make sure to take slow, deep breaths with thorough exhalations, and maintain a calm, relaxed approach while diving to prevent overexertion. This practice not only helps to mitigate narcosis caused by physical exertion but also ensures that you don’t inhale nitrogen-rich gas more quickly than necessary.

Use Straightforward and Familiar Scuba Diving Equipment

Use only scuba diving equipment you are accustomed to when undertaking a deep dive. It’s ideal to be so familiar with your equipment that you can operate it instinctively without having to figure things out on the fly.

If new gear is unavoidable, make sure you thoroughly familiarize yourself with it both on the surface and at shallower depths before using it on deeper dives.

Always Dive with a Dive Buddy

Dive with a trusted buddy, preferably someone with equal or higher dive training. A familiar buddy can more easily identify your abnormal behavior, such as signs of nitrogen narcosis. Likewise, ensure you keep a close watch on them as well.

Extra advice: Plan regular gauge checks with your dive buddy at set intervals (such as every five minutes) and agree to monitor each other. Use appropriate hand signals and make eye contact at specific times. If your buddy misses a check, suppose that he is experiencing narcosis and help them ascend a few feet until reaching a safer depth.

Stick to Your Dive Plan

Design a straightforward dive that’s easy to follow. Stick to the K.I.S.S principle (Keep It Simple, Stupid) and limit your deep dive durations. Additionally, avoid engaging in any strenuous activities during the dive.

Prepare for Emergencies

It’s crucial to master your emergency skills thoroughly, which is why you and your buddy should practice maneuvers like weight ditching and air sharing until they become instinctive. Regularly performing simple checks and mental ability tests during deep dives will also help you determine when it’s necessary to ascend.

If you don’t practice these skills regularly in normal conditions, performing them during stressful situations will be much more challenging. You can’t rely on memory alone for something learned months or years ago—so make sure to practice consistently!

Jot Down Key Information

Using a dive slate can be immensely beneficial, as it allows you to jot down even minor details. This way, you won’t have to worry about remembering things like your dive plan, camera controls, or the locations of your BCD inflate and deflate buttons.

Consider Using Alternative Gas Mixtures

When preparing for a technical dive, think about using gas mixtures that reduce the risk of narcosis. For instance, trimix can be used, which substitutes some of the nitrogen in the standard mix with helium.

Heliox is another option, composed of oxygen and helium without any nitrogen. However, it’s generally more costly and may cause nausea or dizziness. Scuba divers must be specially trained to use these mixtures, and dive shops will require proof of training before providing an air fill.