13 Scuba Diving Rules You Need to Know (OWSI Explained)

All divers learn in the open water course that there are a multitude of rules for you to follow for safe scuba diving.

It can be all so confusing, especially if you are a newly certified scuba diver, or someone that has been out of the water for a while. You’ll tend to be overwhelmed by everything and understandably, forget some of the key scuba diving rules.

While some of the rules can cheekily utilize a somewhat “grey area”, there are some that are absolutely non-negotiable. Violating them can lead to really bad situations and potential injuries that you don’t really want.

A few simple reminders will put everyone at ease and help keep our underwater diving experiences safe for all.

🀒 Never Hold Your Breath

Remember non-negotiable? This is rule number one and the mother of all scuba diving rules. Never hold your breath underwater, especially if you are ascending. Air embolism, also known as pulmonary barotrauma, is not something you want to know about.

Holding your breath can result in an air embolism, which is a serious injury that can have severe consequences. Your lungs are like big air bubbles. Air expands on the way up yes? And if you hold your breath and ascend, the air in your lungs have nowhere to go, and POP!

Well, it isn’t that dramatic. But the air will push against the lung walls, potentially finding its way to arteries or any other organ, resulting in a pressure, or barotrauma injury.

The real bad news is AGE – Arterial gas embolism. It is when all those air bubbles with nowhere to go, choose to go into your arteries, blocking the blood flow to your brain, heart, and other vital organs. You really don’t want that to happen.

Symptoms Of AGE

  • Low blood pressure
  • Joint and muscle pain
  • Dizziness
  • Headaches
  • Blurred vision
  • Irregular heartbeat
  • Loss of consciousness
  • Seizures and convulsions
  • Chest pain
  • Confusion and anxiety
  • Shock
  • Cardiac arrest
  • Unfortunately, also death. AGE is one of the leading causes of scuba diving fatalities.

Treatment of AGE

People suspected of AGE should be given 100% emergency oxygen and hyperbaric compression treatment as soon as possible. AGE should be treated as an emergency, not a “good to have”.

Recompression forces the air back into the body will allow the body to metabolize and dissolve the air.

🐒 Slowly Ascend From Every Dive

Scuba diver slowly ascending

The same pressure rules that make up the golden one also apply to this important rule. Air doesn’t just stay in your lungs, it lives throughout your bloodstream, organs, and joints.

While we metabolize oxygen, we cannot metabolize nitrogen – it has to be dissolved in your bloodstream. Go up too fast, and the excess nitrogen doesn’t have time to dissolve because of the rapid change in pressure and expansion of air. All those bubbles in your bloodstream or joints might expand way too quickly, causing one of the most common dive injuries – decompression sickness or DCS.

Ascend slowly at a rate of about 30 feet (10 meters) per minute and do all your stops to reduce the risk of DCS.

Also, note that the other thing with a bunch of air that will expand, sometimes as much as triple the volume, is in your BCD. Be prepared to purge excess air in the BCD and adjust your buoyancy as you ascend.

πŸ™‹β€β™‚οΈ Always Go With A Dive Buddy

Scuba diving is more fun when shared, wouldn’t you agree? While solo diving also has its perks, it requires many hours more of dedicated training to be solo diver certified.

Four eyes are better than two at spotting cool underwater stuff. It is also a good idea to have a backup air supply within a short finning dash.

The buddy system is there for the reason. The majority of dive accidents and fatalities occur when a buddy team gets separated and the hurt scuba diver is found alone.

The buddy system begins with:

  • Discussing the dive plan
  • Becoming familiar with each other’s gear
  • Performing a pre-dive safety check
  • Keeping an eye on each other throughout the dive
  • Sticking to the plan
  • Safety stop
  • Ascending to the surface together
  • Performing a post-dive discussion
  • Plus you get to share all the cool stuff along the way together!

Underwater, your buddy is your support system. Running out of air or cracking your mask at 30 meters is not going to be good news without one!

⛑️ Don’t Skip The Pre-Dive Safety Check

Remember BWRAF? Some experienced divers tend to skip or shortcut this crucial bit. Check yourself, check your gear, and then do your buddy’s, as you’ll be relying on each other for safety underwater.

  • B – Buoyancy control device. Does it inflate? Everything works?
  • W – Weights. Don’t forget them!
  • R – Regulators. Are both working? Does the air pressure gauge move when you breathe?
  • A – Air supply is on? You cannot know how many seasoned scuba divers forget to turn their tank on.
  • F – Final okay.

🀿 Check Your Scuba Equipment

Scuba diver checking scuba equipment

In addition to the BWRAF buddy check, some additional knowledge is also good. Make sure you know about any integrated weights since you might have to dump them in an event of an emergency. Also, know where the dump valves are for the BCDs of you and your buddy.

If you are planning for an unusual dive, double-check that you have all of the necessary equipment. For example, a primary flashlight, a backup flashlight, and a chemical light when preparing for a night dive.

Make sure they all are fully charged and in proper working condition. Calibrate your dive computer to your new air mix if you’re getting ready for a enriched air dive.

🦺 Safety Stop

Always do your safety stop. It allows nitrogen in your bloodstream to dissolve at a safe rate and helps reduce the risk of decompression sickness. Your safety stop is typically 3 minutes at 5 meters.

Deep Dive

If you are planning to do a deep dive, think about adding deep stops in addition to the 5-meter safety stop, especially if you are near your no decompression limits. You can also ascend to a midway point between your maximum depth and your safety stop and hang out there for a minute or two instead of going straight up.

Deep dives are defined by dives up to 30 meters (120 feet). There are many algorithms to calculate deep stops, but simply put, deep stops are time at depths that are about half of your maximum depth during that dive.

A deep stop can be as simple as a minute at 15 meters (45 feet) and another minute at 8 meters (25 feet).

β›” Dive Within Your Limits

If you are an open water diver with 4 recreational dives, your 5th dive really shouldn’t be churning waters with turbulent currents or in a dark, overhead environment that can trigger claustrophobia.

Scuba diving in a dark environment

What fun is there anyway, in biting off more than you can chew and then being too panicked during your dive to actually have fun? Plus, you’re actually endangering your dive buddy and the group.

Dive within your boundaries and limits at all times, and don’t cave in to peer pressure!

If the conditions are risky, never be afraid to alter your diving destination or cancel your dive entirely.

If you’re sick, or are in an uncomfortable situation, don’t be afraid to let your dive guide know.

Know Your Dive Site

Simply ask your dive guide for some insight on the dive site you’re about to descend into. While you won’t have to know every site, you’ll need to be aware of its challenges and be comfortable with them. For example, swimming through a chimney might trigger claustrophobia in some new divers.

Leave the drift dives, overhead environments, or epic surface swims to when you have more dives under your belt. You’ll know when you feel comfortable handling a more challenging dive site.

⏱ Monitor Those Gauges

Keep a frequent check on your pressure gauge, depth gauge, or dive computer while scuba diving.

Scuba diver keeping a frequent check on his gauges

It’s easy to lose track of time while diving, but you really don’t want to discover you have 50 bar left at 30 meters, or accidentally go into decompression and have to sit out the next few dives.

Don’t assume any information based on previous dives like air consumption which might vary from dive to dive depending on stress, body temperature, exertion, depth, and current, so make sure you always have enough air.

πŸ“ Plan Your Dive, Dive Your Plan

Plan your dive with your buddy to ensure:

  • Emergency procedures are clear
  • Hand signals are clear
  • Lost diver procedures
  • Maximum time and depth

Of course, plans can change quickly in the underwater world where sudden condition changes can happen, but as a rule of thumb, always have a plan and stick to it.

Rule Of Thirds

Although not a hard and fast rule, to be conservative and ensure safe diving, follow the rule of thirds. One third of the air should be on your outward journey, one third for your return journey, and one third more air kept for any safety measures to safety stops.

😷 Don’t Dive With A Cold

Another thing you’re taught on your open water course is not to dive when you have a common cold. This is because your sinuses can be blocked. Two things happen when you have blocked sinuses:

  1. You cannot equalize because the path to your middle ear is blocked
  2. If you manage to equalize, your blocked sinuses at depth prevent air from leaving on the way up, leading to a painful and often severe condition called the reverse block.

Don’t even take a decongestant and descend. The effects of the medication might wear out at depth, your sinuses get blocked, air can’t get out….you get the point.

🚫 Don’t Touch Anything

Get properly trained and develop proper buoyancy skills or keep far, far away from the sensitive bottom. Other divers will get seriously irritated if they see anyone grabbing marine life.

Delicate marine life can be hurt by even a light touch. There are also some species that have their skin coated with a protective barrier.

Also, there are many species of fish that will severely injure you if you touch them, like stonefish, lionfish, and scorpionfish.

πŸ‹οΈβ€β™€οΈ Stay Healthy And Have Reasonable Fitness

Remember that diving in heavier currents, lengthier surface swims, the need to carry gear, and being exposed to different types of weather situations all necessitate physical fitness.

A lack of physical energy and stamina can lead to overexertion, which results in increased air consumption, fear, and accidents.

Tobacco and alcohol use, tiredness, and obesity can all increase your risk of developing decompression sickness.

πŸ“– Rusty? Take A Scuba Diving Refresher Course

Although not a hard and fast rule, taking a scuba diving refresher course is always a good idea if you have been out of the water for a year or two, especially if you are a new diver with few dives.

You’ll practice the vital skills under the supervision of a dive instructor and get a memory boost on all these confusing scuba diving rules and why they are what they are.

Basic skills include:

  • Mask clearing, removal, and replacement
  • Breathe from your buddy’s alternate air source
  • Establish positive buoyancy using inflator button on the LPI (low pressure inflator)
  • Disconnect low pressure inflator hose

πŸŽ“ Final Thoughts on Scuba Diving Rules

Whether you are a scuba diver or even if you’re just thinking of getting into the sport, it’s important to be aware of the basic safety rules. And while we all hope to never have to put these skills into practice, knowing what to do in an emergency can make all the difference.

Just keep these simple safety measures in mind before hitting the open water. Stay safe out there and happy bubbles!

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