Can You Use a Medical Oxygen Tank for Scuba Diving?
As a scuba diver, I’ve been asked so many times if you can use a medical oxygen tank for scuba diving. The tanks do look very similar and after all both aid in breathing but under different environments. A non-diver may wonder why not use a medical tank since it’s pure oxygen and helps patients breathe while in hospitals.
The simple answer to this question is NO. You can’t use a medical oxygen tank for scuba diving because the contents in each tank are different and meant for use under very different circumstances. A scuba diving tank is filled with purified air, it’s like the normal air we breathe but all the contaminants have been filtered out. On the other hand, a medical breathing tank is filled with purified oxygen only.
While both tanks are designed to aid in breathing, scuba diving tanks help divers breathe underwater while medical tanks are designed for use on the surface.
This is only the tip of the iceberg, in the next few paragraphs, I’ll discuss the differences between medical oxygen tanks and scuba diving tanks. Can you use a medical oxygen tank for scuba diving, and so much more.
Keep reading to learn more!
Differences between a Medical Oxygen Tank and a Scuba Diving Tank
Scuba diving tanks contain 21% oxygen and all the other gases found occurring naturally in the air. Including a high percentage of nitrogen (78%). The air in these tanks allows scuba divers to breathe normal air, especially in recreational scuba diving.
Advanced divers such as technical divers will use enriched air to help them breathe properly in extreme depths. The air in these enriched tanks is mainly a higher percentage of oxygen combined with nitrogen or helium.
Divers going over 100 ft. below sea level can’t use the normal air tanks used in recreational scuba diving because the gases compress as you dive deeper. This lowers the amount of air available for the diver which can be risky.
Medical oxygen tanks on the other hand should only contain pure oxygen and no other gases to avoid contamination.
The medical oxygen tanks are built differently meaning scuba diving regulators aren’t compatible with the valve knobs on these tanks.
Scuba diving tanks can’t be filled with medical-grade oxygen or pure oxygen under any given circumstance. These tanks should always be filled with purified compressed air only.
Scuba tanks are designed to withstand high-pressure underwater. Medical tanks are designed for use on surfaces where the pressure surrounding the tank is normal. For this reason, the tanks may not work well underwater due to the surrounding water pressure.
Read More: Does Air in a Scuba Tank Go Bad
Is Medical Oxygen The Same As Scuba Diving Oxygen?
No, medical oxygen is not the same as scuba diving oxygen.
As mentioned earlier, medical oxygen is 100% purified oxygen with no other gases present in the tank.
This is required for the medical tanks to work effectively in delivering oxygen to all the body tissues.
A higher concentration of oxygen will work best to deliver the much-needed oxygen to a patient’s body tissues. This is not possible when using oxygen at its normal concentration of 21% in air.
Patents requiring breathing assistance can’t take in enough oxygen supply to all tissues which will affect their organs’ functionality.
Scuba diving oxygen, on the other hand, is at 21%. Air in the scuba tanks is made by compressing air and purifying it meaning the gasses will occur at normal percentages.
In addition, scuba diving oxygen is available in the scuba tank as part of other gases found in the air.
Why 100% Oxygen Is Not Used In Scuba Diving
100% oxygen is not used in scuba diving due to toxicity issues.
If scuba divers used only oxygen their lungs and all other body tissues will be saturated with oxygen causing convulsions. (Read a more detailed article on oxygen and diving here)
This is quite dangerous while diving as it could lead to fainting and drowning.
Medical-grade oxygen is still important to divers. In case of a diving accident such as barotrauma or severe cases of decompression sickness, divers are required to give the patient 100% oxygen.
This help saves their lives by reintroducing oxygen to their tissues to keep their body functioning. This is of course done on the dive boat as you head to the nearest rescue boat or medical center.
Divers do carry medical oxygen tanks on their dive boats, not for diving but to save lives when the need arises.
Can I Use a Scuba Tank For Medical Oxygen?
Yes, and No.
Scuba tanks can be cleaned and filled with medical oxygen. Scuba Tank cleaning helps keep the tank safe for the user to avoid explosions or fire.
This is done by professionals since they have a better understanding of how to do it. The cleaning should also involve cleaning the valves just to make sure everything is compatible for pure oxygen use.
But if you are considering filling your scuba tank with medical-grade oxygen for personal uses or reasons, this is a bad idea.
Filling oxygen in a scuba tank before cleaning could end up in an accident.
You also need to make some adjustments to the scuba tanks such as changing the valves.
Should you use a scuba tank for medical oxygen? No, avoid converting scuba diving tanks to medical takes especially if you lack the skills and knowledge. If you must, then leave it to the professionals.
Is Compressed Air Same As Oxygen?
No, compressed air is the everyday air we breathe subjected to high-pressure to compress and filter it.
Compressed air contains nitrogen, oxygen, carbon dioxide, water vapor, and other gases. It’s basically the air we breathe but in a purified and compressed state.
Oxygen is part of compressed air but can also occur on its own as seen in medical tanks.
Oxygen is isolated from the other components of air, purified, and compressed. When oxygen occurs on its own it will have a higher concentration than normal oxygen in compressed air.
It’s, therefore, true to say oxygen is part of compressed air but you can’t find compressed air in pure oxygen.
Pure oxygen used in medical tanks must exist on its own to avoid contamination and cause health problems in patients.
Final Take
We’ve seen that you can’t use medical oxygen for scuba diving. 100% oxygen will cause saturation of tissues causing oxygen toxicity which eventually causes convulsions.
We’ve also looked into why scuba divers don’t use pure oxygen or medical tanks for scuba diving. The main reason being pure oxygen will cause toxicity and convulsions and regulators aren’t compatible with medical oxygen tanks.
Medical tanks are important in the diving community especially when accidents occur. But they are only reserved for that particular use and not as a scuba tank substitute.
