Mask Squeeze in Scuba Diving – By Natalie Gibb Scuba Diving Expert

Mask

Have you ever surfaced from a scuba dive with an indentation from your mask on your face? If so, you may have already experienced a mild mask squeeze.

Mask Squeeze is the condition that occurs due to incorrect equalization of the air pressure inside the mask causing the outside pressure at depth to push the scuba mask to a divers face resulting in bursting of the small blood vessels around the eyes.

Serious mask squeezes are rare in scuba diving, but when they do happen, they can be painful and horrifying to look at.

Thankfully, mask squeezes are completely preventable.

What Causes a Mask Squeeze in Scuba Diving?:

A diver’s mask traps a pocket of air against his face . During descent, the air trapped behind the diver’s mask behaves in the same manner as the air trapped in his other body air spaces. As a diver goes down, the pressure surrounding him increases with his depth. The increase in pressure causes the air in his mask and other body air spaces to compress in accordance with Boyle’s Law.

As the air compresses, it creates a pressure vacuum, or suction, on the diver’s face.

If the situation is not remedied, the suction can be so forceful that it damages the diver’s facial tissues and eyes.

 

How to Identify a Mask Squeeze:

Mask squeeze affects a diver’s eyes, cheeks, and forehead.

A diver with severe mask squeeze may have inflammation and raccoon-like bruises over his cheeks and surrounding his eyes.

Mask squeeze may also cause subconjunctival hemorrhages, or bleeding under the thin layer of transparent tissue covering the whites of the eyes.

A diver who has experienced a mask squeeze may have bright red blood spots in the white of his eyes. His eyeballs may even be completely red (like a zombie!).

 

Equalizing a Scuba Mask to Prevent a Squeeze:

Preventing a mask squeeze is simple.

A diver need only equalize the pressure in his mask as he descends by adding air to the mask’s air space.

To do this, a diver exhales into the mask from his nose, much as he would when clearing his mask of water. Many divers exhale small amounts of air through their noses without realizing it as part of their normal breathing cycle. These divers will not need to take any additional steps to equalize their masks.

However, divers who have mastered “mouth only” scuba breathing will need to exhale into their masks periodically during descent. A diver should equalize his mask air space anytime he feels a slight suction on his face from his mask. Of course, it is best to prevent any pressure build up whatsoever, so a good rule of thumb is to exhale into the mask after each ear equalization.

No special action need be taken to equalize a scuba mask during ascent. The air inside a diver’s mask will expand, just as the air in his other body air spaces. The expanding air will simply bubble out from under the skirt of the diver’s mask, and does not present a problem.

Is Mask Squeeze Dangerous? What Is the Treatment?:

Mask squeeze is not usually dangerous and does not cause permanent damage.

It is uncomfortable and embarrassing.

Divers who experience a major mask squeeze, particularly a mask squeeze involving the eyes, should seek the advice of a doctor familiar with hyperbaric medicine. Antibiotic drops may be recommended for the eyes to prevent infection. A diver with an eye squeeze should expect the bright red colour to slowly fade to green or yellow before disappearing, just as any other bruise would do.

“Save a Dive” Kit

SaveaDiveKit

 

Save a dive kits may be a small as a zip-lock bag or as big as a tool box, a diver’s save a dive kit will differ depending upon his needs and type of diving.

Suggested parts for the Basic Save a Dive Kit:

Spare mask strap
Mask straps are one of the most common items to break before a dive. Be sure to select a spare mask strap that fits your mask.

Spare fin strap and buckle
Fin straps break less frequently than mask straps, but they do break.  Be sure to choose the correct strap for you fins.

Spare regulator mouthpiece and zip tie/cable tie to secure it.

A spare regulator mouthpiece is an absolute essential.

Basic o-ring kit
This should include o-rings for low pressure and high pressure hoses, as well as o-rings for yoke tank valves or o-rings for DIN regulators (depending upon which you use).

High pressure and low pressure port plugs for the regulator first stage.

When a diver removes a hose from his regulator first stage, he must plug the hole with a port plug. Bring along both a high pressure and low pressure port plug that fits your first stage (apex first stages have unusually large port plugs).

Small adjustable crescent wrench
This is used to remove hoses from the regulator to replace o-rings.

Hex wrenches/ allen keys
Hex wrenches are used to remove port plugs, as well as for a variety of other applications.

Cutting device/knife
At a minimum, your cutting tool should be able to cleanly slice off zip ties and snip strings and bungee.

Needle nose pliers
Needle nose pliers are great for just about everything that needs to be pulled or tightened.

Small pot of silicon lubricant

This is used for greasing o-rings in dive gear, dive lights, etc.

A lighter

Zip ties and duct tape

Nail clippers

Nail clippers are useful for nipping of zip ties and clipping small items.

White trash bag.
Use a white plastic trash bag as a work surface on dirty or wet areas. This makes seeing o-rings and parts easier, and keeps them clean and dry.

Dry suit zipper wax.

Essential if you use a dry suit.

A DIN-to-yoke or yoke-to-DIN adaptor

This allows you to dive with both DIN and yoke tanks.

• Bungee/ Shock Cord

Bungee can be used to secure lights, create necklaces for back-up regs (long hose configuration), manufacture watch/computer straps, and create octopus/alternate air source holders.

 

 

 

Do I Need to Be a Good Swimmer to Scuba Dive?

Swim2

Participation in a high school swim team is not a prerequisite for scuba certification. Scuba certification swim tests are not timed, and participants can use whatever swimming stroke they desire to pass the test – even goofy ones.

Should All Scuba Divers Be Able to Swim?

This is certainly an interesting question.

People enrol in scuba courses for a variety of reasons. Some state that they want to learn to dive in order to overcome a fear of the water or to learn to swim. I would urge such people to become comfortable in the water by enrolling in swimming courses before ever considering a scuba experience program or entry-level certification.

Diver Confidence:Swim1

While the technique of swimming underwater in scuba gear is very different from the technique of swimming on the surface without equipment, confidence in oneself and one’s abilities in the water does translate to diving.

In many cases, this confidence and ability appear to be directly correlated with a student’s comfort level when scuba diving. Students who are completely certain that they would be able to survive in the water with out scuba gear are certainly much more comfortable using it.

• Basic Diving Skills:

Consider that even a scuba program that does not include a swim test will still require the student to put water in his mask and to remove a regulator underwater.

Students who are afraid of having water in their faces will not enjoy these skills, and would do better to increase their comfort level in the water before attempting to dive.

• Problem Solving:

Scuba diving is an equipment dependent activity, and the reliability of the equipment is extremely high.

However, the remote possibility exists that a diver will need to deal with an equipment-related issue by using emergency management skills such as switching to another regulator, even during an initial dive experience.

Scuba divers do not need to be expert swimmers, but a basic ability to handle oneself in the water without fear or stress is an absolute requirement in my opinion.

Knowing how to swim and float are a huge step in acquiring that confidence. Prospective divers who do not have the ability to stay calm on the surface without a floatation device or who cannot swim (however sloppily) for a short distance should first learn these skills with a professional swimming coach.

A diver who is not confident without his gear is one uncomfortable situation away from panic, and panic, as all scuba divers know, endangers both the person panicking and those around him.

Although knowing how to swim is not required for basic scuba experience programs, it is advisable.

Freediving – Freediving vs Scuba Diving

 

Mariefreediving

What Is Freediving?

Freedivers do not use tanks; they use only their lungs to descend and explore the underwater world. For many scuba divers, freediving sounds like an activity for super-humans.

While freediving might seem intimidating at first, most people can learn to freedive. Like scuba diving, freediving simply takes time and dedication to master. “How deep/long can a person really dive on a single breath?” “Isn’t it dangerous?” “Those people are crazy!”

Why freedive?

Freediving could offer you freedom, a new challenge and increased comfort in the water.

A single breath-hold dive is shorter than a scuba dive, but a freediving session allowed you to be in the water for several hours, and you could cover a lot more ground. The reefs were alive with sounds that you will never hear when diving on scuba. Aquatic creatures are not scared off by the noise of the bubbles and seemed more curious. Plus, the freedom you feel without all the extra gear, relying solely on your lungs for air, is unbeatable. You suddenly feel like you belong underwater with the fish. You are not just a visitor anymore, you are at home.

Safety

Freediving isn’t about taking risks; it’s about minimizing risks to make successful dives. Whether you freedive for recreation or competition, the number one safety rule is always to dive under the direct supervision of a buddy. Freedivers tend to pay careful attention to the safety precautions as they generally are very aware of the potential for blackout

Instruction

Obtaining professional training ahead of time will not only teach you to dive with the proper safety measures in place, it will also improve your technique and minimize your learning curve. Freedive training differs from scuba training because freediving skills require physical adaptation, whereas scuba skills are learned motor skills. In fact, freediving, like mountain climbing, has the unusual distinction of requiring physiological adaptation to an external environment. Divers lower their heart rates, shunt blood to their cores and promote other physiological responses. The more you freedive, the stronger these adaptations become.

When looking for a course to fit your needs, look for one that is comprehensive. You should be learning a lot more than just how to hold your breath and go underwater. Perhaps the most important element is the safety training

 

Gear

Although there is less gear involved in freediving, the gear used is quite specific to divers’ needs. You can make do with the gear you currently use as a scuba diver, minus the tanks, BCD and regulators, of course, but as with many sports there are some gear choices designed to improve performance and make your diving much more comfortable

Long-blade fins

Long-blade fins are probably the most iconic piece of freediving gear. The fins are about 3 feet long and because they push more water with each kick than shorter scuba fins, they get you moving like no other fin can. you can kick less and go farther, conserving energy.

Low-volume masks

Low-volume masks are important because they permit divers to keep more precious air in their lungs rather than having to spend it all to equalize the mask. This increased reserve is useful for equalizing the ears and sinuses in addition to prolonging dive time

Proper wetsuits

Even the slightest chill when freediving can cause your oxygen consumption to skyrocket. Proper wetsuits are also important for safety reasons. A freediver should always be positively buoyant in case of a near-blackout or blackout.

Basic safety rules

  • Do not push your limits without proper education
  • Dive under direct observation of your dive buddy. Tell him/her what you plan to do.
  • Do not hyperventilate (no deeper/faster breathing). It can lead to black out without warning. 2-3 slow deep breaths is enough as preparation
  • Do not go deeper if you feel pressure on your eardrums. Equalize all the time.
  • Accept no discomfort.
  • If problems – drop your weights.
  • Do not exhale, or stop on the way up (it enhances the risk of Shallow Water Blackout). Swim straight up.
  • Your lowest level of oxygen is 20 seconds after surfacing. Keep breathing
  • Rest without moving between dives. Rest twice the duration of your last dive.
  • Secondary drowning (death) may occur up to 24 hours after small amounts of water has entered your lungs.
  • Use a dive line to a secure buoy if you plan to push yourself. Stick to the dive line.  NEVER ever swim passed the bottom weight!
  • Do not take air from scuba bottles. Do not freedive after scuba diving, rest more than 12 hours.
  • Drink lots of water before a freediving session. Do not be hungry, or too full.
  • Do not dive deep when you are cold. Don’t dive with fever, infections or drugs in your body.
  • Evaluate the dive site. Know about currents and good exit points. Do not touch reef or animals (they or you might get harmed).
  • Relax, Enjoy and listen to your body.

 

Freediving offers a challenge that teaches you what you are capable of doing, and it’s often a lot more than you think. Even if you have never thought about trying freediving before, it’s a sport worth exploring. It’s an activity for all ages and a great complement to scuba diving.

It can be a challenging sport or just a new way to experience the underwater world.

So give it a try.monaco_free_diving3

 

Passive Communication and Scuba Diving

US Navy 110615-N-OT964-323 Chief Navy Diver Ry...

US Navy 110615-N-OT964-323 Chief Navy Diver Ryan Oakley, right, assigned to Commander, Task Group (CTG) 56.1, and a Pakistan Navy diver give an OK (Photo credit: Wikipedia)

 

What Is Passive Communication?

 

Passive communication is communication that does not require or provoke a response. During open water certification, student divers typically learn active communication, which involves the use of hand signs, light signals, written notes, or signals made with an underwater communication device such as a noisemaker. Passive communication is more subtle, and relies on factors such as diver positioning and movement. Members of a dive team with strong passive communication skills can confirm that all team members are present, breathing, and calm without using hand signals or otherwise disrupting the flow of the dive.

 

Types of Passive Underwater Communication:

 

Positioning

 

By far the most effective type of passive communication is positioning.

 

During an open water dive, buddies should maintain a side-by-side or a slightly staggered position in a team of two, or a staggered position in a team of three. Divers determine which diver will be on the left/right before the dive, and maintain this positioning whenever possible. Buddies stay within each other’s peripheral vision and no more than a few feet from each other. As long as a dive buddy stays in position, he is “okay” and no communication is needed. However, the moment he moves from his teammate’s peripheral vision, active communication is needed.

 

For example, if one buddy stops to check out an interesting fish, the other should immediately notice that his buddy has stopped swimming and turn to establish visual contact with the buddy. The buddy can then point out the fantastic fish. Another example is a diver who stops to solve a problem. He will lag behind and fall out of position. His teammate(s) should notice, stop, and communicate with the lagging diver to solve the problem.

 

Following and Leading Properly

 

A second form of passive communication is accomplished by a diver fulfilling his role as either a leader or a follower. Before a dive, the buddy team should determine which diver will be leading and which diver(s) will be following. The leading diver establishes direction and swim pace, but the following divers also have an important role to play. They must be attentive to the leader and adjust their positioning to his. If one diver wishes to change direction, ascend, or modify the team’s movement in any way, he communicates his wish with the dive leader. The leader then communicates the adjustment with any other divers, and modifies his actions to accommodate the requested change. As long as no changes are required by the following diver he stays in position, passively communicating with the leader that everything is okay and that he approves of the navigation and pace.

 

 Passive Light Communication

 

Passive light communication is of great use on night dives and on dives where visibility is reduced.

 

Passive light communication works similarly to passive positioning communication. Divers take care to direct their light beams so that they are clearly visible to all team members. Divers use their lights to illuminate the area in front of the dive team. A diver should be able to see his teammates’ lights without turning or glancing over his shoulder. Divers should react immediately if a light disappears.

 

Besides light position, light movement is a good form of passive communication. Light movement (as opposed to light signals), is the manner in which a diver shines his light beam around the dive site. A diver’s light beam should move slowly and smoothly as he looks around. By moving his light beam calmly and deliberately, and by returning his light beam to position in front of the dive team every few moments, a diver passively communicates that all is okay. Jerky, uncontrolled movements indicate a problem.

 

Touch Contact

 

Any diver who faces the possibility of extremely reduced visibility  should be familiar with touch contact signals. Of course, there are both active and passive forms of touch contact communication. Active touch contact communication includes pushes, pulls, and hand movements to indicate stop, start, and entanglement. Passive communication is accomplished by the following diver maintaining a firm but calm grip on the leading diver’s leg or arm to communicate that he is in position and that all is well.

 

Ascents and Descents

 

Passive communication on ascents and descents requires a concentrated effort from all the members of a dive team. In open water, buddies should descend and ascend facing each other, maintaining visual contact between team members, and adjusting ascent/descent rates so that team members stay within a few feet of each other for the entire depth change. As long as the divers maintain this positioning, all can be assumed to be okay and the divers may proceed with the ascent or descent. In the event of a problem, face-to-face positioning allows the issue to be easily communicated.

 

The Take-home Message about Passive Communication in Scuba Diving:

 

Efficient passive communication is rarely taught in open water certification courses, but it is worth perfecting. Passive communication makes diving more efficient by eliminating unnecessary signalling and improves dive safety by encouraging stronger buddy awareness.