Diving is a sport with a huge community of active participants. Most of those participants have been well trained and are well informed about the important truths of the activity.
There is a small percentage of, mostly very novice, divers that have somehow gotten the wrong end of the pointer stick and harbor fears or misplaced notions about diving that are false and potentially dangerous.
I have compiled a small list of usual misconceptions that I often come across.
1. Diving is just swimming with a tank
Diving is a lot more than simply swimming around underwater, breathing from a tank. For one thing, people who are poor swimmers can be great divers and great swimmers can be terrible divers. Swimming doesn’t make you think about buoyancy, how to use equipment properly, how to navigate tricky dive sites, dealing with low light and poor visibility.
When you go swimming you start the second you jump in and kick your legs. When you go diving you start your dive before you get in the water. If the dive is tricky then you might start planning the dive the day before. You will be setting up gear, getting tanks filled and plotting routes. Diving needs planning which is what sets it apart from swimming. Never sell diving to friends by telling them is just swimming with a tank.
2. Scuba tanks are filled with oxygen
I don’t think I could count the number of times I’ve heard novice divers try to be smart and refer to the contents of a SCUBA tank as oxygen. I’m not sure where this misconception comes from but it’s amazing how many fresh divers make this mistake.
I will now, in an attempt to bludgeon this fact into the subconscious of every diver and non-diver alike, state quite clearly that the gas in a SCUBA tank is either compressed air (the air around us shoved into a tank very hard) or a blend of two or three gasses (nitrogen and oxygen at different percentages and sometimes helium in serious tec diving).
If, by some massive error, a diver was to go down with only oxygen in their tank they would quickly fall prey to some form of oxygen toxicity which is extremely dangerous, especially pulmonary O2 toxicity.
View my tips how to maintain dive equipment.
3. The biggest danger in diving is running out of air
Scuba diving is characterized by the fact that a diver will go underwater and breath from a finite air source. The fact that air can “run out” has sparked the imaginations of many, many new divers and non-divers alike. The idea that your air supply would simply stop, leaving you entirely without a lifeline gives people the creeps.
I understand the worry and can sympathize with it – it is a real risk that could cause harm. Though it is by no means a big risk, assuming you follow good diving practices and never dive alone. The number of errors a diver would have to make to end up with no air is formidable, and then you add this to the fact that a trained diver is shown how to breathe from another diver’s air supply or make a controlled and safe ascent if the other diver is unavailable.
Out of air accidents are uncommon and should trained for but not feared. View my article about common mistakes new scuba divers should avoid.
4. Air is used up at the same rate as on the surface
This is another one of those items of dive theory that makes a big difference to a diver’s ability to plan dives and make responsible decisions when underwater, yet it is often missed out of early dive tuition because it is deemed unnecessary to a diver’s safety.
I will spare you the diving physics 101 lecture on why air is used up faster the deeper you go, simply put, the gas you breath gets denser as you go down so you get more air in each breath and thus you finish your tank faster.
There are a lot of new divers out there who simply do not realize this correlation which leads to all sorts of problems and often a nasty revelation further down the line.
5. “I’ll just head to the surface if I have a problem”
The above is an actual quote I heard from a diver, said about ten minutes before he went on his deep dive for his advanced course…safe to say I sat him down and gave him the hard truth very plainly.
A non-diver or novice diver will assume that it is perfectly acceptable to go to the surface when they have a problem. Especially when they see that they are only twenty meters from the surface. This feeling that safety is only a thirty-second swim away leads to the most scary of diving accidents – uncontrolled ascents.
A panicked diver might think that all problems are solved when they break the surface but that is obviously quite incorrect. A fast assent is bad news and massively increases the chance of the diver getting DCS. Eighteen meters per minute, end of lecture.
6. Inflate for up, deflate for down
Almost every student wants to use their power inflater as some sort of elevator button which takes you exactly where you want to go. This is an understandable misunderstanding being as the obvious logic suggests that an inflated jacket will allow you to go up while a deflated jacket will help you sink. This is true, but ridiculously dangerous.
A buoyant assent is very difficult to control and will most likely injure the diver by sending them up too fast. It goes against logic to state that you must deflate your jacket to go up and deflate to go down, but that’s the facts… I didn’t make the rules.
Remember: deflate down, deflate up.
7. I can just do a “re-compression” dive if I get DCS
Here’s a myth that applies to some of the more experienced but misinformed divers, if you get decompression sickness from missing a safety stop or from ascending too fast then you can simply strap on another tank of nitrox and jump back in to finish your deco stops.
This is a fallacy, to fully allow nitrogen to come out requires 100% oxygen, a cocktail of drugs and intravenous injections and a very carefully controlled hyperbaric chamber to gently surface you over a period of hours.
If you try to do it DIY in the sea you will end up freezing to death, go into shock or simply get too thirsty to do any good. Don’t waste time, go straight to a chamber.
8. Anyone can wreck/cave/deep dive if it’s within their depth rating
This is another big issue with the slightly more experienced divers – “the diver card says I can dive to thirty meters so that means I can dive any wreck, drift dive or cave system that falls within that range!” It also means that, although I learn to dive in a three millimeter shortie in the Maldives I can easily do a night dive in a dry suit in Norway… Nope!
Don’t hide behind a dive card, it simply states you have been given basic training to a certain standard, it is not a free pass that allows you to forget your responsibility – if it is beyond your abilities then train for it first and then go for the dive. Challenging dives are great but only when you are fully prepared for them.
9. Sharks will eat you and your whole family if dip your toe in the water
Ok, this is a short one. Everyone knows that sharks hate humanity and are actively building water filled suits so they can amass a land army and hold us hostage for our indiscretions toward the underwater environment…or maybe not.
Sharks are big animals that will protect themselves if they are threatened but this is no different from any other animal. They are not actively seeking to gore us Jaws style, nor are they going to steal your car keys and go drink driving. I think sharks are awesome creatures that deserve respect, not fear. I am much more worried about jellyfish than sharks…those things give me the willies!
This is the only exception to the rule… sharks with lasers are scary! View my tips for diving with contact lenses.
10. When disassembling your gear you should blast your first stage
I saved my biggest pet peeve for last. When you take your gear apart after a day’s diving you should always use a blast from your tank or a clean towel to dry your dust cap on your first stage to ensure there is no grit or water that could destroy the delicate inner workings of the regulator.
What you should not do is blast air from your tank into the open first stage as this does not purge it clean, it forces drips of water and grit that have fallen into the opening since you took the regulator off the tank right into the filter and gradually this ruins your first stage.
Your Thoughts?
I hope this guide to misdemeanors and poorly informed myths has been informative and might have reminded you of a few anecdotes where these exact things have been said or even practiced. If you have any of your own diving myths that bug you then please feel free to write them in the comments section below so we can all benefit. You might also like to view my guide to the best diving destinations or consider booking a liveabroad trip, you can find hundreds of boats and diving trips all around the world.
