Scuba Diving refresher

Scuba Diving Refresher Course: The Scuba Basics

Have you been out of the water for a while? Do you feel like your Scuba diving skills have gone rusty? Or are you a newbie who wants to learn the ropes of this adrenaline-pumping sport? Time to get back to scuba diving basics!

No matter where you are in your scuba diving journey, with our quick scuba diving refresher course, we’ve got you covered!

We have everything that you need to remember, from the very first thing you need to do when your feet touch the sand until you’ve settled back on land!

So shake off those jitters and let us get you back in the water. You can browse through each topic listed below or jump into specific points you need to get refreshed.

Let’s get started!

Scuba Diving refresher

Don’t Forget The Buddy Check!

I don’t know why you would go scuba diving with someone you hate, but even if that is the case, there is no way that you should proceed without this first rule. It is quite a handful to remember, so diver’s devise ways to retain it using mnemonics.

Here is one that could help; it’s always Better With Relatives And Friends when doing this activity.

Buoyancy Control Devices (BCD). Check your BCD to know if everything is working correctly. Are the inflators and deflators in optimum shape? Are all dumps working? Make sure that the straps all lay flat and do not have any slack.

Weights. Secure the weight belt, ensure that you can quickly release the strap using your right hand. Test that the integrated system is operated correctly. Familiarize yourself with how to handle your buddy’s device and vice versa so that you can help each other out in case of an emergency.

Releases. You and your buddy must both be acquainted where the releases are found in each other’s suit. They must be adequately secured, and you should know how to undo them. Commonly, releases are the chest and stomach clips, velcro waistband, tank clip, and shoulder clips.

Air. You must check your tank before taking a dip. Do this for yours and your buddy’s. Let them do the same for you to be very sure. Is the air valve open? When you breathe on the regulators, both the primary and secondary, does the SPG drop? If it does, you need to have that fixed or replaced. Carefully check the hose for damage. Place the octopus, or the extra regulator, between your chin and your ribs.

Final Check. When you think you are done, do a final check of each other. You have to double-check the hose, the clips, and all the things that you will need for the dive. Make sure that you have everything you need; they are all in place and are working correctly.

So, there it is, checking your buddy the PADI – BWRAF way! You may think of your ways of remembering these things by coming out with your mnemonics. Personalize it for a better memory boost.

Scuba Diving Hand Signals

When in the water, it’s impossible to communicate using words, believe it or not! For this reason, you must have a way to relay a message to each other, whether it’s because you want to show something exciting or an emergency that needs to be addressed. You have to get the info across.

But how?

Good ol’ scuba hand signals! You may be familiar with them already. Remember, it was discussed in your Open Water Course. As this is just a refresher, we will discuss it most straightforwardly. Let’s start with the basics.



To signal ascent, just keep a thumb up. It may also mean that you are ending your dive. It can be done at any time if you become uncomfortable underwater.



Make a thumb down signal to indicate that you are ready to descend. 

Turn the Dive Around

Turn Dive Around

Use your index finger to make a circular motion.

Surface OK

Surface OK

If both hands are free, make an O shape by forming a ring above your head. If only one is available, create the same shape by touching your head with your hand; it can either be closed or open.

Underwater OK

Ok underwater

Make a loop with your index finger and thumb, then keep the remaining three fingers extended.



You use this signal to tell your buddy that you want to show something. The instructor does this to indicate that students should watch. Point your index and third finger to your eyes and then at the thing that needs to be observed.



Communicate that something is wrong by making a so-so gesture. It is done by placing your hand flat in front of you and flipping from side to side.


Extend your hand flat, palm facing the person you are signaling to. It’s like mimicking a policeman making a stop sign. Not that I’ve ever been stopped by the police!

Trouble Equalizing

Equalization Trouble

Indicate an ear problem by pointing at your ear. Easy!

I’m cold

Cold Signal

Let your buddy know you are cold by making the familiar shivering gesture. Simply cross arms and make an up and down rubbing motion. Slowly ascend if you get cold because it can lead to loss of reasoning and even motor skills.

How Much Air Left?

How Much Air Check

You have to check on each other periodically ensuring you have enough oxygen left. Put your left-hand flat in front of you. Place your right index and middle finger in the middle of the left palm, as if looking for a pulse.

Oxygen Left: 100 bars

100 Bar left

A 100 Bar signal is indicated by making a T sign with your hands. Hold a finger up after this sign to tell every additional 10 bar afterward.

Low on Air

Low on Air

This situation is relayed to your buddy by placing a closed fist against your chest. It does not indicate a real emergency but a sign that you must soon start the ascent.

Out of Air

Out of Air

Communicate this emergency signal correctly by moving a flat hand against your throat as if slicing it. Your buddy must take immediate action should this happen.

Phew! Enough hand signals to get us started I think! Now, these are just the elementary hand signals. There are many others that you can learn if you want to get into it. But as a rule, you can get by with the above.

Should you insist, there are many online courses available, as well as training with other professionals. You will enjoy them, as these are not exhausting, just try them out!

What to Keep in Mind:

Keeping yourself very well versed with the hand signals is a very noble thing to do. It will make your dive more safe and fun. However, these can only be effected through communication if you can see the message!

Getting in the water, watching all the wonders underneath, can take one’s mind out of everything. This can sometimes be overwhelming to take everything in. You can also get carried away! If not careful, soon enough, you might have swum too far to get anyone’s attention using hand signals.

If this ever happens, and it could, you can use an alternative way to communicate. You can use a device that creates underwater noise.

An underwater noise device is used to create a sound that will get your team’s attention so that you can finally make those hand gestures. It is a hard object strapped on your tank or hand. Bang it lightly on the tank to create the sound.

It is a must-have device to ensure that you will not lose connection with the others. However, do not make it an excuse not to pay attention to everything going around. Enjoy but be responsible enough to be a team player.

Scuba Diving Breathing Exercises

Now, we are on to our next scuba diving refresher course topic: breathing exercises. You might still remember how to do it. But merely knowing is not enough. Perhaps, you would like to improve your air efficiency this time around. That way, you will avoid being always the first one to call the dive.

Don’t get me wrong; it is not a sin to be the one always to have to do it. However, wouldn’t you like to stay down longer and get more of that breathtaking underwater view? I know you do! So let’s do this!

The Need for Breathing Exercises

Should you want to improve air efficiency while underwater, you need to work out your diaphragm muscle. What is the diaphragm, you might ask? It’s the muscle found at the lower rib cage just below the lungs. Primarily, it’s responsible for breathing. It’s dome-shaped and contracts continuously in a rhythmic way.

We all breathe, so why exercise doing it? Yes, we all do, but the problem is, we are fond of lazy breathing. That means we tend to allow it to happen involuntarily. We let the chest muscle do its thing, creating shallow breaths.

What you need to exercise in scuba diving is deep breathing. For this, you need to let your diaphragm work. Taking deep breaths draws air further into your lungs, which causes better oxygen consumption and exchange.

Deep breathing does not happen automatically. To do this, you need to hone this skill and keep practicing it. Here are two ways you can do this:

Exercise lying down

The breathing exercises are not done when you are already in the water, but before you get there. It means that it has to become a lifestyle. You’ll want to get used to this as it’s something you’ll keep practicing.

In the first exercise, you need to lay on your back while you keep your knees bent. Next, put one hand on top of your chest while the other one rests on your stomach. This posture will enable you to feel the muscles to see if they are engaged while breathing.

Breathing Exercise

Start breathing with your nose. Do it very slowly, and be mindful of how your hands will move. If you are correctly engaging your diaphragm, it should be the hand on your abdomen that moves, while your chest barely does.

Ideally, stay in this position and do the exercise until you get to the point where you have comfortably put your diaphragm to work.

Work your breathing rate

You can do this exercise no matter what position you like because what you will do here is control your breathing rate.

It merely means that you will breathe in a way that will not increase your heart rate. To do that, you will have to take slow and deep breaths. Just relax, inhale slowly, and then gradually release the air out.

It will take a conscious effort to do this because we often tend to be careless about how we breathe, but if you like to improve your ability to stay in the water by maximizing your air supply, you must consider this.

Think about it:

The ability to do diving breathing exercises is very crucial if you want to stay in the water longer. Deep breathing also releases stress from the body. Therefore, it is beneficial not just as a refresher course in diving but also in your overall well-being.

Ear Equalizing

You haven’t gone deep if you didn’t experience that pressure in your ears during a dive. Remember that sensation building up on your ears as you descend? It can be frightening at first, especially if you don’t know how to equalize effectively.

Why does this happen? This happens because there is a pressure difference between the outer and inner ear as you go deeper into the water. As the gap goes more significant, the pressure gets more potent too.

Not being able to equalize can lead to significant harm and danger. It can also cut your diving short since the discomfort will keep you from enjoying it. It is, therefore, very crucial that you include scuba diving equalizing in your refresher course. 

Let us recall some of the scuba diving ear equalizing techniques that can help you get rid of the pressure before it gets serious.

Technique 1: Pinch Your Nose

Nose pinch is probably the first technique you learned from your open watercourse. Also known as the Valsalva maneuver, all you need to do here is a pinch, and then you blow through your nose. As the pressure on your throat pushes air to your Eustachian tubes, equalization takes place.

However, this method can be quite problematic. First, you might blow more than necessary that could lead to further damage. You need to know how much is enough to prevent additional pressure buildup. Also, make sure that you release the pressure every five seconds.

Another problem is that if the tubes are locked by pressure already, it may not activate the Eustachian tubes’ muscles. It might not work at all if that is the case.

You mustn’t rely on only one technique when equalizing. Arm yourself with several options so that you have an alternative way should nose pinching won’t work.

Technique 2: Swallowing

When you swallow, it opens the Eustachian tubes, and we know that this phenomenon leads to the pressure equalization between the inner and outer ear. If you do this while pinching your nose, your tongue’s movement will compress air towards the tubes.

The muscles behind the throat are engaged when you swallow. As the tubes open, equalization would happen naturally. Thus, this is another technique that you can keep with you to ensure that you will equalize fast during your dive.

Technique 3 Jaw Control

Another way of equalizing during a dive is by moving your jaw to engage the muscles behind your throat that will open the Eustachian tubes. We have learned previously what this activity does to equalize pressure.

This technique requires quite a bit of mastery. You need to make your soft palate and throat muscles tensed and then make your jaw move forward and then down. It is like you are going to yawn.

It is challenging to do this third technique, but many divers who mastered it can keep the tubes open longer or even continuously as they descend. Wouldn’t it be great to learn that?

What to keep in mind:

Ear equalizing must be done as early and as often as possible. Do you think it must be started once you hit the water? Go back even further. Start while you are yet to put your diving gear on. Then continue equalizing as you descend.

Should you have any trouble equalizing, signal to your buddy. Do not try to pretend that everything is alright. It’s been a while since you last did this, so, understandably, you need to adjust.

Keep the descent slow. Do not endure the pain or discomfort should they arise. Slowly ascend and equalize, then continue going down. Repeat this practice until you feel that you are getting the hang of it.

You may not want to be seen as a novice, but acting like all is fine when it isn’t can be worse. Even expert divers can have trouble equalizing from time to time, especially if they are not careful.

Scuba Buoyancy Calculator

Now, you are back to one of the most over-particular Scuba diving courses, calculating for buoyancy. This refresher course will be a bit more detailed than the others, but it is crucial. You want to go deeper and stay underwater longer? Keep reading to be reminded of how it is done!


Why do you need to calculate? You see, your instructor seems to be just sizing you up. He would then come up with numbers that he says would work to keep you neutrally buoyant, and then it does!

Well, it takes lots of practice, experience, and exposure to different body builds and sizes before you can do that. In short, it takes time to be a master doing it just by the looks. Don’t stress yourself with that for now.

What you need to do is get reacquainted with your skills in calculating scuba weight, and that is what we are going to do.

What affects buoyancy calculation

Several factors are taken into consideration when determining your underwater weight. First is your tank. Is it steel or aluminum? Then you must also measure how heavy the suit is, your BCD, and finally, your own body.

It may seem impressive that professionals can do this method just by inspecting you, but more often than not, they are not precise with their measurements. Yes, it works, but it can be optimized.

That is why it is essential to know how to specifically do the measurements to quickly pinpoint which of the above factors need to be adjusted to be neutrally buoyant.

How to find your buoyancy weight

Step 1 Measure your body

Wearing just your swimsuit, take some weights with you as you wallow into the water. You will know that you are rightly weighted when you can motionlessly float while holding your breath. You must feel the ascent when breathing in and sink when you exhale.

Step 2 Measure your wetsuit

Repeat the procedure in step one, but this time, you must wear your wetsuit. Once you have determined the weight needed to keep your neutral buoyancy, subtract it from what you got from the first step. The difference will be what is the buoyancy required for your wetsuit.

Step 3 Measure your BCD

Your BCD, particularly the older types, can be a source of inherent buoyancy. Modern styles are not as they were in the early times, and different materials have different weight requirements. So, you must do this accurately.

Get the buoyancy of the BCDs by submerging them into the water.  On doing so, vent all valves clear of all the air inside. Rotate it slowly to release the air that could be trapped inside.

Once you see no more bubbles, release the BCDs to know if it is inherently buoyant. Count the needed weights to keep it neutral, and that would be what you will need.

Step 4 Measure your tank

The tank can be made with aluminum or steel, and the pressure inside also varies. How much it is filled also affects buoyancy. A steel tank is preferred since no matter if empty or full; it remains negatively buoyant.

Add weights to your waist belt accordingly based on the measurement that you will get from your overall inspection of the tank that you will use.

Step 5 Add them all up

Now that you got everything measured, calculate your neutral buoyancy by putting all of them together. Check if everything works out by doing the process in step 1.

If you did all the succeeding steps right, you only need a bit of tweaking to get to your ideal scuba diving weight.

What to keep in mind:

The ultimate goal of getting your diving buoyancy weight is to get your neutral buoyancy. There are other ways to do it, like estimating your body weight and then add weights from there.

No matter which method you choose, what is essential is that you do not forget to do your buoyancy test before going on a dive. With the perfect diving weight, you will have a pleasant and slow descent and enjoy your dive!

You can also go here for a nifty little tool to help you calculate your buoyancy weight.

SORTED to Descend

Is everything coming back to you now? Well, we have gone through the first things you need to relearn on this refresher course. We’re almost at the end of it.

We are getting closer and closer to getting there. Now, we move to a new set of acronyms. This time, it is to remind you how to descend safely.

Let’s get sorted! I mean, SORTED. It’s the acronym we will use for this part of your training!

Signal. The first thing you need to do is signal to your buddy and your team that you are ready to descend.

Orientate. Orient yourself with your surroundings. Ensure that you have the right spatial picture of things like where the boat is, which way is the shore, and everything else that will make you familiar with the area. Also, bring a compass with you if necessary.

Regulator. Before descent is the best time to put your regulator in, you may choose to do this once in the water, but you will swallow saltwater in the process. 

Time. You need to be aware of your time. Even if the dive computers can do this for you, self-awareness will help you manage your time while underwater, as well as when you will have to ascend.

Equalize. Begin equalizing even before you descend. We discussed this earlier. Do it as soon and as often as possible. Do not wait for the pressure to kick in before you do.

Descend. Start descending carefully. Once the BCDs are deflated, you are on your way to explore!

That is it! Just keep it SORTED! It is so easy to remember and to apply, right? Can you almost smell that seawater? You are on your way to getting it all back! One more course in this refresher and you will be good to go!

Scuba Diving Gear Must-Haves

You have all that you need to know to get back to the water, but you also need the gear! You cannot dive without your stuff and equipment. However, knowledge is not enough, arm yourself with the right gear to ensure safety.

Scuba Gear

You likely have them somewhere around the house during your previous dives, eons ago. But this list will help you check if you got all that you need. So, get your pen and paper ready and see if you have everything on the list.

Dive Gear Checklist

Diving Mask

A full-face mask will allow you to see the beauty underneath the water. There are full-face masks with snorkels, but they usually cannot hold up too much under extreme pressure. Moreover, not everyone favors using snorkels, especially most professional divers.

Drysuit or Wetsuit

The decision to wear a wetsuit or a dry suit will depend on which waters you will dive into. Drysuits are usually worn in places where the waters are cold, while wetsuits are for warmer climates.

Diving Fins

Fins help make you move around the water seamlessly without having to use too much energy.

Its ability to help reduce water resistance will allow you to swim faster and more conveniently go against currents.

Dive Boots

Your dive boots are worn before the fins. They will keep your feet warm and prevent skin irritation that may come from getting in contact with the diving fins’ material.

Scuba gloves

The scuba gloves will complete your diving outfit by keeping your hands warm while under the sea. It can also serve as protection from injuries should you touch anything while diving.

Scuba Weight Belt

A weight belt is your primary tool in ensuring that you are neutrally buoyant to prevent you from floating and give you a nice descent.

Scuba Tank

As earlier discussed, it’s made from steel or aluminum. It holds the oxygen that you will need to breathe while diving, so it is very crucial. If you decide to become a frequent diver from now on, investing in one is a good idea.

Scuba Regulator

It is an integral part of your breathing gear as it regulates the oxygen and reduces the pressure so that you can safely and comfortably breathe through your mouthpiece.

Dive Gauge

The dive gauge helps you monitor how much air you have consumed. It also shows how deep you have reached.

Dive Computer

You will need this to be aware of how long you have been into the dive and the depth you reached. It keeps you on course, in-case you like to wander!


The diver’s jacket. It’s worn for optimum buoyancy. It has adjustable buttons to manipulate to ensure that you do not suddenly float to the surface or sink too deep.

Additionally, it holds together all the other gear, such as the tank, the gauge, and the regulators.

There you go! Do you have everything on the list? If not, you must begin shopping now so that you can soon go back diving! Check out our detailed buyer’s guides if you need any recommendations. We only vouch for products we’ve tried and tested!

Parting thoughts:

Scuba diving is a fun sport and recreational activity. For sure, you remember how it felt being down there, one with nature’s wonders.

It is fun, yes. However, you have to keep this scuba diving refresher course in mind because it can also be dangerous if you are careless. Go over the topics one last time, and you are sure to master all the scuba diving basics you need for the most fantastic and memorable dive of your life!

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