Why is removing your mask every time you surface a dangerous practice? No, it's not because a mask on a forehead signifies distress – if that were true, then rescue divers would be deployed for over 50% of divers on the surface, and most diving advertisements would show distressed models. No, it's not because the mask could be knocked off by a wave. That would be an inconvenience, not a safety hazard. Read on to find the real reason why it could actually make the difference between life and death.
Next to not dropping weight belts on the surface, we believe the next most common factor in diver injury and drowning is sudden and/or unexpected facial immersion resulting in stress, panic, and rapid ascent with breath holding.
This is a cascading series of problems that can easily be prevented by simply kissing the water hello before every dive, breathing underwater without a mask for 3-4 comfortable breaths, and by keeping the mask on until you are out of the water. The following information shows how we came to make pre-dive "kissing the water hello" and keeping the mask on, a standard for all our instructors and students.
Our trainers have well over 150 years of active diving, and teaching over 20,000 students in over 15 countries. We have also conducted research on this specific issue, which served to reinforce our observations over these years of diving and teaching diving.
We observed over 1,000 certified divers performing regulator retrieval and mask removal & clear skills in a warm water, 18 ft deep tank at the Underwater Explorer Society in Freeport, Grand Bahamas. We have detailed data recorded for over 300 divers. The results provided much useful information including:
Divers bolted over 95% of the time after they replaced the mask on their face. Why?
Most people are nose breathers, and unless divers are continuously trained to be reflexive mouth breathers underwater, they will reflexively inhale through their nose when they are stressed. These divers frequently inhale through their nose underwater, which has no immediate ill effect as long as their mask is dry. Problems arise when the mask leaks, floods or is dislodged.
These divers flag themselves in three main ways:
These flags are very important to catch because these divers are a significant danger risk if they experience mask problems or other stresses in the water. They do not belong diving until they learn how to be completely comfortable:
Think about it, if divers always, reflexively remove their mask at the end of the dive or when waiting on the surface, what are they telling you about them and their mask - they are not comfortable with it. If they were completely comfortable with it, they wouldn't remove it. They will often tell you they remove it because of fogging, but after they are taught how to properly clean the mask, they still remove it when it stays clear.
We do not allow divers to remove their masks until they are out of the water. They must learn to become so comfortable breathing through their mouths, and so comfortable wearing their mask, that they forget they are wearing a mask. Once this is accomplished, the chances of them ripping it off when panicked underwater are very slim.
We will also not allow any of our students, regardless of diving experience, to dive without first demonstrating they can comfortably breath underwater without their mask for one minute. We find that approximately 30% of divers cannot do this, and as the water becomes colder or the current increases, this percentage rises.
It would be negligent to allow divers who cannot comfortably breathe without a mask, to dive. They should also be fully comfortable breathing with a flooded mask, which is actually more difficult than with no mask - if they are not comfortable mouth-breathers. If they cannot do this, then what will happen when their mask floods or is dislodged underwater? They will most likely aspirate water, panic, rip off their mask, spit out their regulator, and bolt to the surface, putting them at risk of lung overexpansion injury, near drowning, drowning, and possibly decompression sickness if they are nitrogen loaded.
All our trainers and students must submerge their face and breath at least 3-4 times on their regulator with no mask before every dive. This serves three important purposes:
What is torso or inhalation reflex? Remember the last time you stepped into a pool, lake, ocean or shower that was colder than you expected? What did you reflexively do? You probably gasped and then possibly yelped. That gasp, a sudden inhalation, a reflexively sucking in of breath, is caused by what sometimes is termed the torso reflex.
Cold and/or painful sensations can result in a series of physiological and psychological responses. To give you an idea of what cold water is, we lose heat at the same rate in 80° F water as we do in 42° F air. One hypothesis for the gasping reflex is that when the body is suddenly exposed to cold water it knows it will need additional oxygen to meet the demands of increased metabolism. Metabolism is increased to increase heat production.
The gasping is probably also caused by the shock of the cold sensation that we may not have expected. We can respond by gasping and even hyperventilating when we are shocked by just about anything. Pre-dive facial acclimation by "kissing the water hello" will decrease the chances of this process occurring to divers who face sudden facial immersion underwater.
To summarize, three important accident prevention measures are:
If you have any questions regarding these or other matters, please do not hesitate to contact us at Lifeguard Systems.
Safe Diving Always,