Deep Diving: Rules, Recommendations And Fun Facts

Deep Diving: Rules, Recommendations And Fun Facts
Jon Milnes

How deep do you dive?

It’s often the first question a diver gets.

And what is the real answer to that question?

Have you been diving at a reef edge or a vertical wall where you see life at greater depths? Do you want to go deeper, but your training and experience limits you?

Here are some facts that you need to know about deep diving.

What is Deep Diving?

Deep Diving is any dive deeper than 20 meters (60 feet). However there are different kinds of diving which gives deep diving its own specific definition. In Recreational diving, the maximum depth limit is 40 meters (130 feet).

In technical diving, a dive deeper than 60 meters (200 feet) is described as a deep dive.

However, as defined by most recreational diving agencies, a deep dive allows you to descend to 18 meters and beyond.

Decending to the Wreck
Decending to the Wreck
Photo by: Jon Milnes

Risks in Deep Diving

Deep diving is relatively safe as long as you follow all the rules and procedures. However, it is important that you know the inherent risk of diving at greater depths.

Decompression Sickness (also called the bends)

When you dive, you breathe in air which is composed of oxygen, nitrogen and other gases. Your body uses the oxygen but nitrogen is eventually released over time since our body does not need it.

So, when pressure suddenly drops, like in the case of a rapid ascent, nitrogen gas inside your body expands and develops into bubbles. These bubbles are usually trapped in the joints causing severe pain. A diver with decompression sickness is treated using hyperbaric oxygen therapy inside a recompression chamber.

Read more about Decompression Sickness and How to Treat it

Jon Milnes

Nitrogen Narcosis

You will experience a narcotic effect when you accumulate too much nitrogen. The first symptoms are tingling of the fingers, dizziness and disorientation. It also affects your sight by experiencing a tunnel vision which makes reading gauges and instruments difficult. The deeper you go, the greater the effect of nitrogen narcosis is.

Rapid Air Consumption

The air you breathe will become denser as you go deeper due to increasing pressure. Meaning, you consume more air while deep diving as compared to diving at shallower depths. So it is highly recommended that you constantly monitor your pressure gauge.

You can also bring an additional small cylinder or a pony bottle, some stage a decompression tank at the safety stop line.


Rules, Recommendations and Tips for a Safe Deep Dive


  1. Plan your dive. Establish your maximum depth and bottom time.
  2. Always perform the Pre-Dive Safety Check before diving.
  3. Regularly monitor your depth and pressure gauge. Make sure that you have plenty of air in your tank for your ascent.


  1. Do not plan your dive so that it exceeds the No Decompression Limits of the dive table.
  2. Never dive alone and always have an experienced buddy with you.
  3. Never go beyond your planned depth nor exceed your bottom time.

How to Get Started

Your first deep dive should be under the supervision of a dive instructor. You can do this during your Advanced Open Water Diver course. You will be trained to dive to a depth of 30 meters (100 feet). You may also have the option to enroll in a Deep Diver Specialty course wherein you will be trained to dive as deep as 40 meters (140 feet).

After your certification, you may plan to go deep diving with an experienced dive buddy. Some deep diving sites may take you to shipwrecks or may require you to use an enriched air to extend your dive time. So you may also consider enrolling in other specialty courses like wreck diving, peak performance buoyancy and enriched air diver.

Dive as it’s any other dive

    1. Get in the water and set your dive watch and establish orientation or direction using your compass.
    2. Once ready, signal your buddy to start descending and slowly deflate your BCD.
    3. You should descend closely together until you reach your planned depth. Watch your buddy for signs of Nitrogen Narcosis.
    4. While descending, you may feel a sudden change of temperature called the thermocline. Just continue with your dive as this occurs naturally.
    5. Never go beyond your planned depth nor exceed your bottom time.
    6. Regularly monitor your depth and pressure gauge. Make sure that you have plenty of air in your tank for your ascent.
    7. Before you start ascending, signal your buddy and you should always ascend together.
    8. Make sure that you deflate your BCD when ascending to prevent rapid ascent.
    9. Ascend slowly and strictly follow the normal ascent rate no faster than 20 meter (60 feet) per minute.
    10. Make sure to do a safety stop at 5 meters (15 feet) for 3 minutes. Deploy your DSMB before your last ascent.

Some of the World’s Famous Sites for Deep Diving

Lighthouse Reef Blue Hole (Belize, Caribbean Sea) – this site was created from an ancient cave system. It almost has a perfect blue circle measuring 300 meters (1,000 feet) in diameter. You can enter an underwater cave where you will be amazed by the amazing stalactite formation. You can also reach a deep coral reef that starts at 33 meters (110 feet) and slopes down to 135 meters (450 feet).

View of the Blue Hole in Belize
View of the Blue Hole in Belize
Photo by: Wata51

Blue Hole (Dahab, Egypt, Red Sea) – known as one of the world’s most dangerous dive sites due to the number of lives it had claimed.

You start your dive by descending through a vertical hollow space in between coral mounds. You will exit through at 27 meters (90 feet) in clear water where you will find a vertical wall. This wall plunges further down to profound depths.

Downside Look of Blue Hole, Egypt
Downside Look of Blue Hole, Egypt
Photo by: Kristina Vackova

Blue Corner Wall (Palau, Micronesia) – You will definitely enjoy this vertical drop-off that starts at 10 meters (30 feet) and plunges down to over 330 meter (1,000 feet) deep. You will find large schools of fish, sharks, turtles, giant groupers, barracudas and many more. Blue corner wall is considered as one of the best dive spot in the world.

Deep diving sites are not only confined in saltwater environments. The Eagle’s Nest Sinkhole in Weeki Wachee, Florida is a freshwater pond. Underneath lays a large chamber with crystal clear water. You start your descent by entering a chamber that leads to the “Main Ballroom”. This is a very large and deep cavern that plunges up to 91 meters (300 feet) deep. Eagle’s Nest is considered as the Mount Everest of Diving and one of the world’s complex dive sites.

World’s Deep Diving record

With the purpose of connecting an underwater pipeline, a team of commercial divers reached a depth of 534 meters (1,752 feet). They used a specially-mixed breathing gas for this job. This happened in 1988 off the coast of the Mediterranean Sea.

The deepest scuba dive was recorded at 332.35 meters (1090.45 feet). This was performed in 2014 in by Egyptian diver Ahmed Abdel Gabr. This dive was declared as the Guinness World Record for Mankind’s Deepest Dive.

The world’s deepest wreck dive was recorded at 205 meters (676 feet) while diving in the Yolanda Wreck in Egypt. This was performed in 2005 by Leigh Cunningham and Mark Andrews.

Do you deep dive?

There’s big difference in what diver like? Some like the shallow dives as other want to go deep. What do you prefer?


Notify of

Newest Most Voted
Inline Feedbacks
View all comments
Go to Frontpage