SCUBA Diving 101

Welcome back to my SCUBA diving series! I have always been fascinated by the underwater world, and one of the best ways to explore it is through SCUBA diving. As Jaques Cousteau said, “The sea, once it casts its spell, holds one in its net of wonder forever,” and I am indeed spellbound. If you are too, read on to learn the basics of SCUBA diving. Warning: this is a really long post.

   To begin, a diver must know what each piece of equipment is before they use it. One of the most essential pieces of diving equipment is the BCD, which is an acronym for buoyancy compensator device. The BCD is inflated or deflated to ensure you’re neutrally buoyant (which means you stay at the same depth when immobile) by pressing the inflator or deflator buttons. The BCD is inflated with air from the air tank traveling through the low pressure inflator tube. The low pressure inflator tube is simply a tube that supplies the BCD with air. The air tank is a diver’s air supply; it stores air and allows him or her to breathe underwater. The regulator is connected to the air tank. The air in the air tank is highly pressurized, and needs to be decompressed before it is breathable.  This job is done by the regulator, which attaches to the diver’s mouth so he or she can breathe. Divers are also required to have alternate air sources, in case of emergency. There are three common types of alternate air sources: the octopus, alternate inflation regulators, and a redundant air supply. The octopus is essentially just another regulator for use only as an alternate air source. As for alternate inflation regulators, they simply attach to the BCD inflation hoses. Redundant air supplies are completely different units, with their own separate tanks. Air tanks are attached to the diver’s BCD with tank straps. Divers also wear weights to obtain neutral buoyancy, and these are either attached to the BCD or worn as a belt. A diver also wears a wetsuit to keep them warm underwater, fins to help them move efficiently, and a mask so they can see underwater.Image result for scuba gear diagram

    Now that I’ve discussed the necessary equipment, onto the pre-dive procedures. First, divers must always swim with a buddy for safety reasons. A diver and his diving partner need to do a pre-dive safety check before every dive. To begin, divers examine their BCDs. A diver must confirm that his BCD is properly attached and the low pressure inflator is connected, and that his tank is securely appended to the BCD. If the type of entry they’ll be performing requires it, the diver must inflate their BCD. Divers then check their weights and confirm that they can take them off quickly in case of an emergency. Then, the diver tests the regulator with a few breaths and shows his or her buddy the location of the alternate air source. Finally, the divers inspect each other’s equipment. 

      The next step is entering the water. There are multiple methods of entry depending on what environment the dive will take place in. Here are a few examples:

   Giant stride; this method is for use on a dive boat with a platform, a pier, or some other stable structure with deep water underneath. To do this, the diver dons his gear and partially inflates his BCD to avoid sinking quickly when he enters the water. The diver then stands on the edge of the structure with his fins hanging over the edge. Next,   the diver attaches his mask and regulator, holding them in place with his fingertips as he steps off of the platform. When the diver is in the water, he must bring his legs together and float to the surface. Finally, he should signal his buddy that he entered safely.

  The second method of entry to be discussed is the backward roll entry. This technique is best for small boats. The diver begins by sitting on the side of the boat with his tank facing the water. He then checks for people or things in the water behind him, and if the water is safe he holds his mask and regulator in place as he falls back into the water. The diver must be sure to keep his legs bent at the knees and his chin tucked.

  This next technique is best for shallow water. It is called the controlled seated entry. The diver must change into his gear on while on the boat and swing one leg over the side of the boat. As he carefully swings the other leg out, a diver then must slowly lower himself into the water and be careful not to hit the boat.

  Obviously, divers need to know how to enter the water from the shore as well. If the diver is entering the water from a beach, he should walk backwards into the water with his fins in his hand. The diver then inflates his BCD and leans on his buddy while he puts his fins on. When he is deep enough, the diver submerges and swims to deep water.

  To enter a rocky coast, a diver needs to think ahead and leave any unnecessary gear at home. Divers should always wear protective footwear as they search for a safe entry point, and then secure their fins and mask when they find one. A diver then scoots himself into the water with his legs first and must try to time his entry with a swell. When he is in the water, the diver must swim as fast as he can towards deep water to avoid being carried back to shore.

   When the diver is in the water, he needs to know how to descend. The first step of a typical descent is signaling your diving partner that you are ready to go down. Before the divers descend, they should observe their surroundings and find a landmark so they are able to orient themselves. Generally the ship’s anchor is a reliable orientation point, but if it becomes dislodged somehow the diver might want to have a backup plan. Also. divers should be sure to check the strength and direction of currents. Next, a diver must test his regulator and make sure the device in his mouth is, in fact, a regulator and not a snorkel. Then, he sets his diving watch or computer so he doesn’t stay underwater too long. Finally, he descends down into the water. The divers must take a few deep breaths to calm themselves, deflate their BCDs, and make sure to equalize their ears every few feet. For a diver to equalize his ears, he simply swallows and wiggles his jaw with his regulator still in his mouth. If the diver descends too quickly, he can simply add air to his BCD by pressing the inflator button.

    Now the diver has descended, and there are two main ways for him to move around underwater; the flutter kick and frog kick.  The flutter kick is basically the same as freestyle kick, simply kick one leg above the other in a scissor-like motion, then kick the other leg above the other and repeat. For one to effectuate a frog kick, he must do a breaststroke kick. This is when a diver kicks out to the side with his feet flexed, then straightens his legs and brings them back behind him.


   Most deadly scuba accidents are due to human error and not faulty equipment, but there are a few fixable malfunctions that occur most often. First of all, one of the most common equipment problems is a flooded regulator. To fix this, the diver simply presses  the purge button or exhales deeply through the regulator. To contrive getting water out of a flooded mask, one must press their fingers on the top of the mask to secure it against their forehead and exhale through his nose. The air exhaled will force the water out of the mask. Another common problem with SCUBA gear is a dislodged regulator. To fix this, the diver sweeps his arm backwards to grab the regulator, or one might bring his hand to the tank and follow the tubing. When the regulator is back in the diver’s mouth, he should press the purge button and continue. Another setback divers may face is a free flowing regulator, which means the regulator fails to cut off the air supply when the diver stops inhaling. To continue utilizing air from the regulator, one must tilt his head to the side and drink the air like a water fountain. A diver or his diving buddy may run out of air underwater, so they will need to either know how to share a regulator or understand how his buddy’s alternate air source works. To share a regulator, divers must pass the regulator back and fourth between the two of them until they surface. 

  In case of an emergency, there are a few kinds of ascent that divers need to learn. For any ascent, one should proceed as slowly as possible and take safety stops along the way. The reason for this is that underwater, a diver’s body builds nitrogen up in his tissues, which are released into his bloodstream when he ascends. If the diver does not allow these gasses to be released on his ascent he could get decompression sickness, which can cause paralysis and even lung collapse. Now, the first kind of ascent I will be teaching is the normal five point ascent. 


     First, diving partners should signal to each other that they are ready for ascent, then check the time on their dive computers to ensure they have enough time to surface. Next, he should look for any other divers or boats at the surface and signal to them that he will be beginning his ascent. Finally, the divers will swim slowly to the surface and confirm neutral buoyancy throughout the ascent. Since air expands as divers enter lower pressure zones, they will need to continue releasing air from their BCDs as they ascend.

   The second kind of ascent I will be teaching is the alternate air source ascent. If a diver runs out of air and needs to use his buddy’s alternate air source, this is the kind of ascent he would perform. First, the diver finds his buddy and starts using his alternate air source. Then, divers signal that they are out of air and need to go to the surface. Finally, the divers hold hands to ensure they do not drift apart as they deflate their BCDs and they swim upward. 

    Thirdly, I will enlighten you on the controlled emergency swimming ascent. This ascent is used when the diver is out of air and his buddy is not nearby. First, one must substantiate that they are neutrally buoyant. The diver then begins swimming upwards as slowly as possible and releases air from his BCD on the way up. Divers often use this as a gauge for speed, knowing they should ascend more slowly than the bubbles rise. Divers should always look up to make sure nothing is obstructing their path to the surface. One must remember to exhale as he rises because air expands as the pressure decreases. 

   This last method is the buoyant controlled emergency ascent. This method is one of the most dangerous because the diver may float to the surface too quickly, but if properly executed it is suitable. To begin, the diver releases his weight belts and swims horizontally while the air in his BCD lifts him to the surface. If the diver is ascending too quickly, he should deflate his BCD until he reaches a proper speed.


   Now that the diver is at the surface, he has finished the dive. The process is not over, however, because there are a few basic maintenance things one needs to do after every dive. To keep his gear in good condition, the diver must rinse everything in fresh water after each dive. Before rinsing his BCD, he should contact the manufacturer for instructions. Generally it is safe to soak the BCD in a large container full of freshwater, but one should always exercise caution when handling expensive equipment. To clean masks, flashlights, and other small items, one must soak them in a tub of warm water. For divers to maintain their regulators, they should soak them in hot water. Finally, the diver simply must hang everything up to air dry. To extend their longevity, all equipment should be stored in a cool, dry place.

    Knowing all of this information, divers can experience a fantastical new world in a safe way. I have explained the seven main points of a dive: the pre-dive safety check, how to enter the water correctly, how to descend safely, the most efficient ways of swimming underwater, how to react to certain problems you may come across during the dive, how to safely ascend from the depths, and how to care for your equipment so you’ll be ready for the next dive. There is one last thing a diver should remember while diving, though. As SCUBA diver Vanessa Vitri so eloquently said, “What  all divers should remember is that SCUBA diving is a fun exploration of life. When you dive, don’t take yourself so seriously. Loosen up and relax. The point of SCUBA diving is not to focus on yourself; it’s to focus on the beauty of the underwater world.” 

Thank you for reading this! I hope you’ve enjoyed this series so far, and if you have please like and comment!


    Van den Berg, Marcel. “Diving Hand Signals Used by Dive Instructors IDC and Divemasters PADI.” YouTube, YouTube and IDC Koh Tao, 25 Mar. 2017,

   Brown, Richard. “SCUBA Equipment Set-up Demonstration.” YouTube, YouTube, 6 Dec. 2011,

   Dennis, Gerrard. “Why Are AIR’s Not More Popular?” Simply Scuba UK, June 2011,


   Gibb, Natalie. “What Is a CESA?” ThoughtCo, June 2017,

   Gordon, Bill. “Predive Safety Check.” YouTube, YouTube and NOAA Diving Program, 15 June 2016,

   Hardy, Jon. “Alternate Air Sources.” Scuba Diving,


   Hunt, Natalie, and Guillaume Fargues. “Alternate Air Source Ascent – PADI Skill Circuit – Divemaster and IDC.” YouTube, YouTube and Ban’s Instructor Development, 16 Mar. 2017,

   Carl. “How to Rinse Your Scuba Gear.” YouTube, Meraki Diving, 14 Apr. 2016,

   PADI. “PADI Scuba Diving Skills: Mask Clearing.” YouTube, YouTube and PADI/ Professional Association of Diving Instructors, 5 Feb. 2008,

   PADI. “PADI Scuba Diving Skills: Mask Clearing.” YouTube, YouTube and PADI/ Professional Association of Diving Instructors, 5 Feb. 2008,

   Smith, Melissa. “Learn to Scuba Dive.” Scuba Diving,

Smulders, Etoile. “The Adventure Junkies • Your First Step Into The Great Outdoors.” The Adventure Junkies,

   “What Is the Peak Performance Buoyancy Course and Why Should You Take It?”, The Scuba Page Magazine, 12 Feb. 2018,

    Various authors. “Scuba Diving Quotes.” Scuba Diving Quotes,

One thought on “SCUBA Diving 101

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s