A pressure of 6.3 kPa—the Armstrong limit—is about 1/16 of the standard sea-level atmospheric pressure of 101.3 kilopascals (760 mmHg).
Although the highest pressure to which organisms are known to be exposed on Earth does not exceed 150 MPa, laboratory results indicate that at least a fraction of the population of bacteria or complex life forms can survive exposure to pressures far above this threshold.
Humans have survived for two years at 5,950 m (19,520 ft, 475 millibars of atmospheric pressure), which is the highest recorded permanently tolerable altitude; the highest permanent settlement known, La Rinconada, is at 5,100 m (16,700 ft).
On the ground the body is exposed to 0.21 atm, but the human body has an “operating range” from about 0.14 to more than 2.0 atm. Above this range (or after long term exposure) oxygen can become toxic to the body, below this range, oxygen deprivation will lead to reduced performance, unconsciousness, eventually death.
20 ATM = 200 meters or 660 feet
Those that do are amazing — otherworldly, in the realest sense of the word. You have to hold your breath for an insane amount of time to free-dive. Also, if your watch is marked “professional diver,” you can go scuba diving.
At oxygen levels of 10 to 14 percent, faulty judgment, intermittent respiration, and exhaustion can be expected even with minimal exertion (Exs. 25-4 and 150). Breathing air containing 6 to 10 percent oxygen results in nausea, vomiting, lethargic movements, and perhaps unconsciousness.
Within 15 seconds, deoxygenated blood begins to be delivered to the brain, whereupon unconsciousness results [1]. Data from animal experiments and training accidents suggest that an individual could survive at least another minute in a vacuum while unconscious, but not much longer [3,4].
The highest barometric pressure ever recorded was 1083.8mb (32 in) at Agata, Siberia, Russia (alt. 262m or 862ft) on 31 December 1968. This pressure corresponds to being at an altitude of nearly 600 m (2,000 ft) below sea level!
Thanks for any answer! 2 atmospheres in analogous to scuba diving in 30 feet of water.
In order to breach the human skin the ejection pressure has to be at least 100 pounds per square inch (psi)8 while most high-pressure guns and injectors reach pressures of 2000 to 12000 psi3. The puncture wound is small, inconsiderable and not distinct.
High pressure means high performance. The 10,000 PSI line of tools includes the strongest cutter manufactured today: the S 700. Plus, these high-pressure rescue tools are built a bit lighter and are faster to the point of resistance.
The lowest tolerable pressure of air is about 0.47 atm (475 millibars of atmospheric pressure) - recorded at 5950m altitude. At about 0.35 atm (less than 356 millibars at around 8000m) life is impossible. Pulmonary and cerebral edema lead to death.
But if someone were to dive from the surface of the ocean to a depth of 10 m, the atmospheric pressure exerted on them doubles from 1 to 2 atm. If they dive to 20 m, the pressure is 3 atm.
The above devices have been certified to 5ATM standards. This means that they are water resistant to up to 50 metres in depth for 10 minutes. They are now suitable for low-velocity and shallow-water activities, including swimming.
What is the highest pressure a human can withstand? Using normal atmosphere, people can function at 2.5 times atmospheric pressure, or 2.5 bar. At 2,5 bar, a person inhales enough oxygen molecules to equal a lungful of pure oxygen at normal atmospheric pressure.
The world record for lowest pressure (at sea level) was 652.5 mmHg recorded inside Typhoon Tip on October 12, 1979, in the western Pacific Ocean.
A normal person is capable of a breath pressure of 1-2 psi, so by pressure breathing you can increase your lung pressure from 10.1 psi to 11.1-12.1 psi during each exhale, closer to the 14.7 psi you are used to.
It's also very cold in space. You'll eventually freeze solid. Depending on where you are in space, this will take 12-26 hours, but if you're close to a star, you'll be burnt to a crisp instead. Either way, your body will remain that way for a long time.
Pressures within the lungs can be raised to 130 centimetres of water (about 1.8 pounds per square inch) by the so-called Valsalva maneuver—i.e., a forceful contraction of the chest and abdominal muscles against a closed glottis (i.e., with no space between the vocal cords).
A long time ago, before humans, dinosaurs, plants, or even bacteria, Earth's air had no oxygen. If we could time travel to that period, we would need space suits to breathe. Scientists think the air was mostly made out of volcanic gases like carbon dioxide.
Not really — at least, not for humans. Oxygen levels were probably at about 4-5 percent around this time, so we would be nowhere near the 21 percent we're used to breathing. Mostly, the air would have been nitrogen and greenhouse gases. Again, it's likely that you'd suffocate without a breathing apparatus.
If our atmosphere was 100% oxygen, plants and cyanobacteria on land and sea would likely not exist as we know them, because they require carbon dioxide to live, with oxygen being a byproduct of their metabolic respiration. Therefore, the insects and animals that depend on them would also likely not exist.
While the recommended maximum depth for conventional scuba diving is 130 feet, technical divers may work in the range of 170 feet to 350 feet, sometimes even deeper.