Best Answer

Given a solid suit or vehicle, where pressure is maintained near normal sea-level (1 atmosphere), there is obviously no limit, except that we haven't yet built a machine that can with-hold that type of pressure yet. But for humans without such protection, the pressure levels in water below 1000 feet (300 m) present severe problems.

(see related links)

Modern recordsA Navy diver submerged 2,000 feet (609.6 m), setting a record using the new Atmospheric Diving System (ADS hardshell suit), off the coast of La Jolla, CA, on Aug. 1 2007.

The deepest open circuit Scuba dive was accomplished by Pascal Bernabé (Ralf Tech/WR1 Team) who on July 5, 2005 descended to 1,083 feet (330 m). The dive took place near Propriano, Corsica.

Re-Breather UseThe options for modern exploration are most commonly open circuit scuba and re-breather. Diving is limited by the correct mixture of breathable gases. On open circuit "classic" scuba the gas must be mixed ahead of time, while on re-breathers a diver always has the right mix of gas for the depth. Australian diver David Shaw successfully used a modified recreational re-breather to reach a depth of 888 ft (270 m) in fresh water in 2004. (Shaw died on an attempt to recover a fellow diver's body in 2005.) Oxygen RequirementsThe maximum depth that you can dive safely on air is dependent upon the partial pressure of oxygen. The air that we breathe at the surface is at a partial pressure of 0.2 bar .The partial pressure increases as your depth increases : at 10 metres it will be 0.4 bar and at 20 metres it will be at 0.6 bar. Oxygen becomes toxic at approximately 1.6 bar partial pressure, giving a maximum safe diving depth on ordinary air of around 70 metres (230 ft) . Diving to this extreme depth is not recommended, as individuals tolerances may vary. Deep-diving Gas MixturesThe maximum depth someone can dive will be directly related to the percent of oxygen in the breathing mixture. The air mixture we as humans breath is mostly made up of oxygen and nitrogen. The ratio is around 80% nitrogen and 19% oxygen and 1% other gasses. The same gas, oxygen, that keeps us alive can become toxic and kill us under high pressure. But one way to prevent oxygen toxicity is to reduce the concentration of oxygen and replace it with a different gas, such as helium. Since our bodies only use about 5% of the 19% of oxygen in air, we can replace a portion of the gas with something that is relatively safe under pressure. This is called a tri-mix gas. It can be used to dive much deeper than the recreation limit of 130 feet (40 m). Another physiological problemAs the previous answers all indicate in one way or another, the primary limiting factor in most cases at least is PPO2 (partial pressure of oxygen) and various gas results including hypothermia, which gases like helium exacerbate. However, in super-high pressures, there is a problem with denaturing of various proteins in the human system. This rare and unlikely problem is still in the books and not reality, as human descent to such depths and ambient pressures has never been tried. When the Trieste descended to 36,000 ft (10,900 m) in 1960 (Marianas Trench), the people inside were protected at one atmosphere. It's likely that with exposure to extremely high pressure, human physiology may fail, for reasons unrelated to gas problems.

Proteins denaturing is detectable by increased neuropathy. Given a "perfect" gas mixture, this could eventually prove fatal. Divers Alert Network (DAN) was the source of this, with the USC Catalina Chamber circa 1970, and may have indicated problems with the medullary sheath as well.


Obviously the limit for recreational diving as it is defined by PADI (Professional Association of Diving Instructors) is 40m. This would be achieved using ordinary nitrox (a mixture of oxygen and nitrogen; basically air but with a slightly higher percentage of oxygen). For BSAC and SSAC (British Sub Aqua Club and Scottish Sub Aqua Club) the limit is 50m, but it is generally acknowledged that beyond 40m a decompression stop on ascent is required. BSAC and SSAC both teach deco as a part of their dive training courses. The purpose of decompression is to allow bubbles of nitrogen to escape from the blood and prevent DCI (Decompression Injuries); also to increase and decrease the air volume in the lungs and sinuses at a safe rate to minimise the effects of barotrauma on the air spaces (which are otherwise liable to implode). Technical divers scuba dive at greater depths, and one of the methods they might use is an open circuit rebreather as has been discussed above; alternatively multiple cylinders and pony bottles. Oxygen toxicity occurs as a result of the increased pressure and can result in seizures (the pressure increases with depth at a rate of one atmosphere per 10 metres) and for this reason the maximum depth at which air can safely be breathed is much debated. The general consensus is that it is around the 60m mark but of course it varies from person to person and it would be unwise to venture beyond the defined limits of recreational diving without appropriate technical training.

Through diving with various complex gas mixtures individuals have managed to reach maximum depths of around 300m, but would probably have to be taken straight to an onsite hyperbaric chamber afterwards. Pressure underwater increases at a rate of an additional atmosphere per 10 metres. The effect of this upon the lungs and sinuses is that they experience a 'squeeze' - the air volume within these air spaces in fact halves with every additional atmosphere! Divers are taught to 'equalise' (add air to the air space) their sinuses to maintain the same air volume and avoid discomfort or worse when diving. They are supposed to do this as they ascend or descend and it is achieved by pinching the nose inside the mask and breathing out, thus using the air from the lungs. The effect of the increased pressure on the lungs is less noticeable because the lungs are comparatively so large and flexible, but obviously there is little that can be done to equalise them. Generally speaking the lungs are not dangerously subject to barotrauma at depths safe to dive using air, but as you can imagine, at 300 metres the pressure has increased by 30 atmospheres, meaning the air volume of the lungs has been compacted 30 times! At greater depths than this the lungs would quite simply implode, or else could explode on returning to the surface due to excessive expansion.

User Avatar

Wiki User

โˆ™ 2012-01-02 20:15:03
This answer is:
User Avatar
Study guides

Add your answer:

Earn +20 pts
Q: What is the maximum depth a human can dive to?
Write your answer...
Still have questions?
magnify glass
Related questions

What is the maximum depth a scuba diver can dive to?

The recreational depth limit is 130ft.

What is the maximum depth a human can dive until the pressure kills them?

Unprotected humans can go (on average) 350 feet underwater.

What is the maximum depth a human without scuba gear can dive?

The current world record for no-limit freediving is 214 meters, set by Herbert Nitsch in 2007.

How do i dive on Zelda Ocarina of tme i press 'a' and just return to the surface again?

To dive push and hold "a". You return to the surface either when you let go of "a", reach your maximum dive depth or when you reach the bottom. The starting maximum dive depth is 3 seconds. To increase your maximum dive depth go to the zora's domain and play the diving game as a child. If you succeed then you will gain the silver scale which allows you to dive for 6 seconds. When you become an adult go to the fishing game and get a fish that weighs at least 15 lbs and he will give you a golden scale, allowing you to dive for 9 seconds.

The Nautile, a French submarine, can dive to a depth of 20,000 feet. It takes 20 hours to dive to the maximum depth at the speed of x feet per hour. How fast must the Nautile dive to reach the maximum depth?

This is a speed related question!!! Speed = distance / time Hence speed = 20,000 ft/ 20 hrs. speed = 1000 ft/hr

How far down can a scuba diver dive?

Maximum depth for a recreational scuba diver is 130 feet.

What is maximum allow bottom time according to recereation dive planner?

Of course it depends on the depth, but the maximum is 219 minutes at 10.5 meters.

Why is it dangerous for submarine to dive below its maximum depth?

Excessive water pressure at depth would implode the Sub destroying it and all soles within.

What is the minimum depth a human can dive to?

The minimum is about 2 feet since that is deep enough to completely cover the body.

How deep is the average ocean scuba dive?

Most recreational divers rarely dive below 100 feet. The average depth for a dive is around 60 feet.AdditionThere is a difference between the average deepest depth of of dives in general and the average depth of a single dive. Most dives will have the deepest depth of around 60 feet, but the average depth of that dive will probably be more in the range of 30 feet since divers will start at one depth and usually continue the dive at shallower depths.

What is the maximum depth of the ocean?

Eleven kilometers is the maximum depth of the Pacific Ocean.

What is the maximum depth of Lake Ontario?

the maximum depth of lake ontario is 244m or 803ft

People also asked