There is no fixed answer. Everyone has different physical and technical experience and will have different results. The most important thing is that the depth of the dive affects the speed at which the diver consumes air.
Deep water diving time
0-10m 120 minutes
10-20m 60 minutes
20-30m 40 minutes 30-40m 30 minutes
tidal
We all know that it is the influence of the moon, but the tide is very important to divers. Usually there will be a rise or a retreat in 6 hours, and one of the two big tides (relative to a large tide) must be careful, and the water flow at this time will be particularly strong.
visibility
This refers to the degree of transparency in water. In general, winter is better than summer, morning is better than afternoon, and the reef shore is better than the sand bank.
Air plug sieve (embolim)
This is the diver's most important dive disease. Divers breathe high-pressure air through the air cylinder under the water, and if the high-pressure air is sucked up, the diver will immediately rise and it will lead to rupture of the alveoli. Air pressure is low. The air in the lungs will enter the blood and stop the blood circulation. So when you rise, you can't stop breathing, you must keep a big, slow breath.
Nitrogen drunk
Typical divers have this phenomenon when they are about 30 meters deep. Nitrogen drunk will make people think and judgement lower. When serious, it will lead to death.
Diving time safety watch
Water depth time limit water depth time limit
10 m no 27 m 30 minutes
12 m 200 minutes 30 m 25 minutes
15 m 100 minutes 33 m 20 minutes
18 m 60 minutes 36 m 15 minutes
21 m 50 minutes 39 m 10 minutes
24 m 40 minutes 42 m 10 minutes
This watch is only suitable for those who have not dived within 12 hours
Decompression disorder
If nitrogen cannot be eliminated from the body, it will cause small air bubbles to destroy the body tissue and interfere with blood circulation. Therefore, please follow the dive safety schedule.
Carbon dioxide poisoning
There will be rapid breathing. Headache and vomiting, when diving, try to avoid stopping breathing (in order to stay a little longer) or do too intense movements in deep water.
poisoned by carbon monoxide
Carbon monoxide is not present in normal air cylinders, but it is not possible to pour gas into unfamiliar places (when the compressor is aerated, carbon monoxide is poured in at the same time due to poor exhaust gas).
How long can a cylinder of air dive?