Bends

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What are the bends in scuba diving?

The bends – more properly known as decompression sickness – are something you need to be very aware of when scuba diving.

If you dive deep, if you dive for a long time or you come back up too fast, well…

That’s when decompression sickness can be a serious danger. In fact, in extreme cases, it can kill you.

But don’t worry:

In this article, you will learn all about decompression sickness, the symptoms of the bends and how to avoid them.

What is decompression sickness?

Decompression sickness (DCS) or “the bends” is also called Caisson disease.

It is caused when bubbles of gas (most commonly nitrogen) form in the body tissues due to changes of pressure which occur during scuba dives (or aerospace or high altitude events when the participants experience quick changes of pressure from sea level).

These bubbles can have a range of negative effects on almost any part of your body.

Why is decompression sickness called the bends?

When DCS was first discovered and written down in medical journals, the term “the bends” related specifically to the joint pain which is perhaps the most common symptom.

The other symptoms had similar colloquial names – such as “the chokes” and “the staggers” – as we’ll see below.

What causes the bends?

When you dive beneath the water, you experience greater pressure than you do when at sea level.

As you dive, the pressure may cause the gases in your air tank to dissolve into your body tissues. This is sometimes called “on-gassing.”

Then, as you come back to the surface, the pressure is reduced and the gases should slowly leave the tissue. This is often called “off-gassing.”

However, if the ascent is too fast, the gas will not leave your body’s tissues safely. Instead, tiny bubbles of it will be formed and remain. This is what causes the bends.

Picture it like a bottle of soda. In the closed, pressurised bottle, all is well. You only see all of the carbon dioxide bubbles fizz out of the drink when you take the top off and release the pressure.

Although any kind of gas in a diver’s tank can be affected in this way, nitrogen is the problematic one. This is because your body has no use for nitrogen. All it does is build up in the tissues, prevent blood from flowing properly and stretch or damage the nerves.

The released gas can also cause an embolism, cause blood to coagulate or vasoactive compounds (these are natural agents in your body which decrease or increase blood pressure or heart rate) to be released.

The risk of DCS is increased by:

  • The depth of the dive
  • The duration of the dive
  • The rate of ascent

Decompression sickness – symptoms

The symptoms of decompression sickness are usually found to affect the musculoskeletal and nervous systems.

They almost always develop within 48 hours of the dive (or another event) taking place. However, it is more common for them to develop within 6 hours or even within the first hour.

Some of the most common symptoms of the bends include:

  • Joint pain – especially around major joints like the shoulders and elbows. The original name for this symptom alone was “the bends”.
  • Weak or numb upper extremities – the fingers and forearms.
  • Chest or abdominal pain – when the gas affects the torso. If this is worse when the affected diver is breathing in or it develops into coughing, breathing difficulties, blue lips or blue skin this is the most dangerous form of the condition and needs to be addressed immediately. This also went by the catchy name of “the chokes”.
  • Lower back pain – divers suffering from DCS often find their spinal cord is affected.
  • Weak, numb or even paralyzed lower body – this is again due to the dissolved gas affecting the lower back.
  • Incontinence – if the gas affects the sphincter or urine valve.
  • Fatigue – far more than any given activity should cause.
  • Swollen glands – when the lymph nodes are affected by the gas.
  • Confusion, decreased awareness or restricted or lost vision – these occur when the gases affect the brain.
  • Difficulty walking or with balance – sometimes called “the staggers”, especially when paired with ear ringing, deafness or vomiting caused by the above symptoms.

A note on skin rashes

Skin rashes which are very itchy or which appear red or marbled in colour are often cited as being a symptom of the bends. They are sometimes colloquially known as “the creeps”.

However, these tend to be more related to pressure changes experienced by portions of the skin which were not properly covered by the wet suit.

They may also appear when someone is in the hyperbaric chamber. Again, this is because of pressure changes.

Decompression sickness – treatment

If you or anyone you dive with experiences any of the possible symptoms of the bends you should seek treatment for decompression sickness immediately.

It is important to tell the doctor or staff at the emergency care facility you visit that you have been diving in the past 48 hours so that they know that DCS is a likely cause of your condition.

1) Professional treatment for the Bends

A hyperbaric re-compression chamber is the device required for treatment of DCS:

  • Hyperbaric treatment can take as long as 12 hours or more depending on the severity of symptoms.
  • The chamber is a pressurized environment which reduces the size of the bubbles and helps them to be reabsorbed.
  • It also provides large amounts of oxygen to the damaged tissues.

Before treatment in the re-compression chamber, a doctor will usually test the person suffering from the condition and hook them up to IV and oxygen lines.

Afterwards, hospital admission for monitoring of their status is a likely outcome.

2) Emergency care for DCS

Calling the local emergency services should always be your first port of call when a case of the bends is reported.

Be sure that the professional you are speaking to understand:

  • The diver has decompression sickness.
  • They need to be transported lying flat on their back.
  • If they are going to be airlifted, the vehicle should travel below 1000 feet if at all possible – or be pressurized to sea level.
  • A hyperbaric chamber will almost certainly be required for their treatment, so in the hospital, they will be taken to needs to have one. You can search online for where the closest chamber to you is on the Divers Alert Network website.

If you absolutely cannot reach a hospital in time, there are a few things you can do to keep a person suffering from the bends stable until help arrives:

  • 1. If they experience a drop in body temperature, keep them warm with blankets.
  • 2. If you have an oxygen mask, put it on them.

Don’t dive until you’ve dived with the experts

Avoiding getting the bends is relatively simple:

Don’t go scuba diving without getting some proper instruction and supervision first. There are several organizations which will certify that you know how to dive safely.

You want to be on the lookout for NAUI (National Association of Underwater Instructors) or PADI (Professional Association of Diving Instructors) courses to make sure you are getting qualifications which are recognized internationally.

At the Ko’ox dive shop here in Playa Del Carmen, we instruct fresh-faced new divers in how to scuba dive in safety each and every week with our PADI courses.

Get in touch with us before you take the plunge and we’ll show you how to dive safely – with no risk of getting the bends.

The Bends – Chemistry LibreTexts

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  1. Introduction
    1. The Solubility as a Function of Temperature
    2. The Solubility as a Function of Pressure
  2. Symptoms of the Bends
  3. Prevention
  4. References
  5. Problems
    1. Answers
  6. Contributors and Attributions

The Bends is an illness that arises from the rapid release of nitrogen gas from the bloodstream and is caused by bubbles forming in the blood and other tissues when a diver ascends to the surface of the ocean too rapidly. It is also referred to as Caisson sickness, decompression sickness (DCS), and Divers’ Disease.

Introduction

As divers descend into the ocean, the external pressure on their bodies increases by about 1 atm every 10.06 m. To balance this it is necessary to increase the pressure of the air they breathe from tanks or pumped to them from the surface so that their chests and lungs do not collapse. Unfortunately, our bodies aren’t used to the pressurized air (because we normally breathe air under normal atmospheric conditions). With higher air pressure in the lungs Henry’s Law tells us that gases such as nitrogen, helium (when used in diving gas mixtures) and oxygen become increasingly soluble in the blood. Unlike oxygen which is metabolized, nitrogen and helium build up throughout the body  When divers want to emerge from the water, they have to make sure they don’t ascend to the surface level too quickly because they risk numerous bubbles forming as the nitrogen/helium re-equilibrates, much as when a pressurized bottle of soda is suddenly opened. When nitrogen (N2) gas forms bubbles, it accumulates and saturates the muscles and blood, causing pain. Called the Bends, this condition can also cause injuries involving the nervous system.

Figure taken with permission from Wikipedia Commons.

The solubility of a gas is the ability for the gas to dissolve in a solvent (in our case, blood, which although it contains organic components is essentially an aqueous solution). Both temperature and pressure affect the solubility of a gas.

The Solubility as a Function of Temperature

  • In water solvents, the higher the temperature, the less soluble the gas is.
  • In organic solvents, the higher the temperature, the more soluble the gas is.

The Solubility as a Function of Pressure

English chemist William Henry discovered that as the pressure increases, the solubility of a gas increases. Henry’s Law is then:

\[ C =k P_{gas} \]

where

  • C=solubility of a gas in a solvent at a specific temperature,
  • Pgas is the partial pressure of the gas, and
  • k is Henry’s Law Constant

In the case of The Bends:

  • If a diver goes deeper and deeper into the water, more nitrogen builds up in the bloodstream and other tissues.
  • Following Henry’s Law; as the pressure increases, the solubility of nitrogen in the diver’s bloodstream increases.
  • As a result, nitrogen from the compressed air stays in the bloodstream and other tissues
  • However, since the diver is in a highy-pressurized environment, the excess N2 can only be relieved when the diver ascends to levels with lower external pressure
  • Ideally, this should happen during the diver’s gradual rise to the surface
  • Unfortunately, sometimes , the diver ascends too quickly, resulting in the rapid formation of  bubbles, which interfers with nerves, blood and lymphatic vessels and leads to  excruciating joint pain and clotting.

Example \(\PageIndex{1}\):

Determine Henry’s Law Constant, k, with the information that the aqueous solubility of N2 at 10 degrees Celsius is 11.5 mL N2 / L and 1 atm.

\( k= \dfrac {11.5 mL N_{2}/ L}{\ 1 atm} \)

Now if the Pgas of N2 increases to 5 atm:

\[ P_{N2}=\dfrac {C}{\dfrac {11. 5 mL N_{2}/ L}{\ 1 atm}} \]

\[ 5 atm=\dfrac {C}{\dfrac {11.5 mL N_{2}/ L}{\ 1 atm}} \]

Solve for C: C= 57.5 mL N2 /L

Therefore, both examples show that as the the pressure increases from 1 atm to 5 atm, the solubility of the N2 gas increases from 11.5 to 57.5 mL N2 / L. This supports Henry’s Law.

Symptoms of the Bends

  • Joint pain
  • Fatigue
  • Itching and rashes
  • Coughing and chest pain
  • Dizziness and paralysis
  • Unconsciousness
  • Death

Most symptoms occur 24 hours after decompression, but can occur up to 3 days after.

Prevention

  • Ascending to the surface slowly (rate of 60 ft/min.)
    • The slower the diver surfaces, the more slowly the excess nitrogen is equilibrated and the lower the impact on the diver
  • Spending time in a decompression chamber
    • Chambers that high-pressured divers are placed in.
    • Once in the chamber, the diver is immersed in a high pressure environment which is slowly reduced, minimizing any effect.
  • Breathing a compressed air mixture of helium and oxygen with no nitrogen.
    • For deep dives, in addition to the Bends, excess nitrogen can lead to decreased mental function. This is called nitrogen narcosis.
    • Helium is less soluble in the blood stream and thus does not build up as much, providing a smaller threat to divers and is used for deep dives.

References

  1. Petrucci, et al. General Chemistry: Principles & Modern Applications: Custom Edition for CHEM 2 (Hardcover). Upper Saddle River: Pearson Education, Inc., 2011.
  2. Phatak, Uday. “Decompression Syndrome (Caisson Disease) in an Indian Diver.” Annals of Indian Academy of Neurology. Online-Only Journal. 13.3. 2010 n.pag. web. 30 May 2011.

Problems

  1. What is Henry’s law?
  2. How does Henry’s law relate to the Bends illness?
  3. How does temperature affect solubility?
  4. How does ascending to the surface make the bends less prevalent?
  5. Why is breathing the compressed helium/oxygen mixture better than air with N2?

Answers

  1. \(C =k *P_{gas}\) (where C=solubility of a gas in a solvent at a specific temperature, Pgas is the partial pressure of the gas, and k is Henry’s Law Constant)
  2. As the pressure increases, the solubility of gases in the diver’s bloodstream increases. Henry’s law states that the solubility of a gas increases when the pressure increases.
  3. As temperature increases, the solubility of gases decrease in aqueous solutions. In organic solutions, the solubility of gases increases at higher temperatures.
  4. When diver surfaces slowly, he/she will have a reduced impact of pain from the bubbles that form. Instead of rapidly forming and causing joint pain, the slow rise to the surface creates a steady loss of pressure, resulting in pain that is not as severe.
  5. Helium is less soluble in the blood stream, providing a smaller threat to divers when they come up to the surface of the ocean. Fewer bubbles are formed, meaning that the divers encounter less pain as they ascend.

Contributors and Attributions

  • Dhara Shah (UCD)
  • Josh Halpern (LibreTexts)

What Are ‘The Bends’? – Add Helium

The bends might sound like a dance move or a  cool hangout. The reality is much less fun, I promise you. 

The bends is a common term used to refer to decompression sickness. It’s a condition that primarily affects deep sea divers but it can also happen at high altitudes to mountain climbers or air passengers. 

Caused by a sudden change in pressure, the bends can kill in extreme cases. Even mild cases can cause long-lasting damage to your tissues, joints, and lungs. 

So let’s take a closer look at the bends and how you can avoid it. 

Causes

When you dive with compressed air your body gets more oxygen and nitrogen than it’s used to at the surface. The oxygen is used by your muscles and organs to continue functioning. 

The nitrogen is not used. It dissolves into your blood and hangs out there until it can be filtered out by the liver and the kidneys. 

The deeper you go, the more pressure your body is put under. This pressure encourages the gases in your body to dissolve into your blood more quickly and efficiently. This goes for the good and bad gasses. 

When it’s time to come to the surface the pressure decreases as you swim upwards. This reduces the pressure on your body. Less pressure means that the gases that were previously dissolved in your blood become gas again. 

Think of it like a bottle of soda. Before you open the bottle it looks liquid. When you turn the cap, bubbles rise out of nowhere to the surface. This is because the pressure within the bottle is reduced when it’s opened. 

Now, think about what happens when you open an agitated bottle of soda. It fizzes over, right? Well, that’s what the bends is. 

If you rise to the surface too quickly, the dissolved nitrogen turns back into gas and bubbles out of your tissues. In large quantities, this causes significant problems for your tissues.

After all, your blood and other bodily tissues are not designed to have huge amounts of high energy bubbles ripping through them.

Symptoms

The symptoms of the bends develop within 48 hours of the dive though in extreme cases they can develop within the first hour. Mostly, you’ll notice symptoms developing within about 6 hours. 

The symptoms mostly affect the muscular-skeletal system and the nervous system.

One of the first symptoms of the bends is severe joint pain. It affects big joints like shoulders, hips, and elbows most severely. In fact, this symptom is why decompression sickness came to be known as the bends. It would cause the joints to bend leaving the sufferer bent double. 

With the joint pain comes numbness and tingling in extremities, lower back pain, and numbness, or paralysis in the lower body. The bubbles cause huge damage to the tissues that supply the body with oxygen and nutrients. Without oxygen, the limbs and organs can’t function properly. 

The reduced oxygen also affects the brain. People suffering from the bends might find that they are confused, fatigued, unbalanced, and short of breath. 

Treatment

The bends is usually diagnosed by your diving history and symptoms. Blood tests and x-rays don’t usually show the problem. 

If you notice a member of your party is suffering from the bends you need to get them to a hospital as quickly as possible. 

You will need to make sure that the emergency services know that the person is suffering from the bends as adjustments will need to be made. 

First and foremost, a person suffering from the bends needs to be transported lying flat on their back. If they are going to be airlifted, the helicopter needs to fly below 1000 feet or be pressurized to sea level. This is to prevent exacerbating the problem. 

The treatment for the bends requires a hyperbaric chamber. You’ll need to make sure that the hospital you are headed for has one available. You can search for your closest hyperbaric chamber online. 

Once admitted, you will spend up to 12 hours in a hyperbaric chamber. The time will depend on the severity of the case. 

A hyperbaric chamber is a pressurized chamber that replicates the pressure of a deep-sea dive. It allows the gas bubble to shrink and be reabsorbed into the bloodstream. The chamber is slowly depressurized and the gases are safely removed.

The chamber also provides huge amounts of oxygen to damaged cells to allow them to repair themselves. 

Prognosis

The prognosis of patients suffering from the bends is generally good providing they can access medical care. Usually, one hyperbaric treatment is sufficient to cure the bends. 

Some symptoms like joint pain and fatigue can linger for days or weeks after treatment. If you are not better after your treatment, your doctor may recommend further treatments.  

Prevention

There are a number of ways to reduce the risk of getting the bends. The most important thing is to remember to rise slowly. You need to take time at different depths to adjust to the pressure. 

You should also not spend longer than the recommended time at your maximum depth. There are tables that allow you to work out how long you can stay at different depths. 

Avoid flying within 24 hours after you’ve been diving. You need to avoid putting your body under unnatural pressures while the gases safely escape your body. 

It is also a good idea to maintain general healthy practices before and after diving. You should not drink alcohol before diving, avoid hot tubs, saunas, and steam rooms after diving, and avoid diving if you have been feeling unwell. 

Final Thoughts

The bends is a painful condition that can cause serious, long-lasting damage if not treated.  

In the early years of diving, the bends was often fatal. However, as technology and medical understanding improved, divers are more aware of the dangers of the bends, and doctors are better equipped to treat it. 

Despite being curable, the bends is not something you want to experience. Avoid it at all costs where possible. 

The bends: anatomy of decompression sickness

Home Topics Science & Environment The bends: anatomy of decompression sickness

Scuba diving can transport you to a magical underwater world, but in rare cases the pressure can be dangerous.

By Jess Teideman

August 21, 2012

Reading Time: 4 Minutes •
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(Credit: Getty Images)

IT WAS A BRIGHT winter day in 2001 at Kingscliff in northern NSW, and 18-year-old Daniel Trollope was on one of his regular dives to the reef. It wasn’t until the rugby union player got to his first decompression stop at 5m that things started to go wrong. He felt exhausted and noticed sharp pains in his lower back.
 
“When I got to the surface, I blacked out and had to be pulled into the boat,” Daniel, now 28, says. “I could hear everything around me, but couldn’t even open my eyes.”
 
Back on dry land he walked to waiting paramedics. That was the last time he walked. Daniel, an experienced diver who says he’d followed all safety procedures and used both dive tables and a dive computer, was suffering a severe case of the bends – which happens in roughly one in 20,000 dives. After 16 visits to the recompression (hyperbaric) chamber, he regained some feeling, but was left with symptoms similar to spinal-cord injury.

Decompression sickness (DCS), known as ‘the bends’ because of the associated joint pain, is a potentially deadly condition caused by bubbles of nitrogen gas forming in the blood and tissues. It’s most common among divers using scuba tanks, but can affect free-divers and people at high altitude.

Associate Professor Michael Bennett knows all too well its effects on the human body. Michael and his team at the Department of Diving and Hyperbaric Medicine at the Prince of Wales Hospital in Sydney treat about 60 cases of the bends – ranging from mild to severe – each year.

“Inexperienced divers have an increased risk because they have more difficulty following safe-diving practices,” he says. “They’re more anxious, or are unsure of the processes, and are [therefore] more likely to ascend rapidly or have equipment failures.”

How ‘The Bends’ works

The air we normally breathe is a mixture of gases, mostly nitrogen and oxygen (78 per cent and 21 per cent, respectively, at sea level).  Both dissolve into the blood, but unlike oxygen, which has a vital metabolic function, nitrogen is inert and is expelled as we breathe out. At 10m, the pressure your body is subjected to is almost double that at the surface. As water pressure increases, so does the amount of nitrogen absorbed. This remains dissolved in your blood and tissues until your return to lower pressures at the surface.

As you ascend, nitrogen diffuses out of the tissues and is expelled in your breath. The problem comes if you ascend too fast – dangerous bubbles can form in the blood and tissues. It’s similar to what happens with a can of carbonated soft drink, saturated with dissolved carbon dioxide. When the pressure is released by opening, the gas rapidly forms bubbles. Imagine how violently gas can depart a shaken can, and you get a sense of the potential damage to the body’s organs.

The bubbles lead to a range of symptoms, which emerge soon after you surface. Pain is often the first indicator, Michael says, usually in the joints and muscles – and many divers mistake it for muscle fatigue. Other symptoms include unpleasant itchiness and skin rashes caused by bubbles in and under the skin, as well as headaches, dizziness and nausea. That’s in mild cases of decompression sickness. More serious damage can be done to arteries.

“When bubbles form, they can travel down blood vessels and wreck the inside lining,” says Lieutenant-Commander Dr Peter Smith, officer in charge of the Australian Navy Submarine and Underwater Medicine Unit. “Blood vessels are designed to be kind of Teflon-coated [non-stick]. But the bubbles can rip off all the coating, then everything starts to stick, and the blood vessel can become leaky and stop working. When that’s happening all over your body, it can cause a lot of damage.”

In the most serious cases paralysis, brain damage, heart attacks and breathing difficulties can result. It’s possible for the bubbles to enter the brain and spinal cord. In these cases, the damage can cause tingling, numbness and unconsciousness. Damage to the brain can cause vision impairment, headaches, confusion and problems with balance and coordination. Cases that lead to strokes, seizures, paralysis and death are often due to arterial gas embolism: air bubbles that form in one place but get lodged in the heart, lung or brain.

How to avoid The Bends

The best way to avoid DCS is to follow advice on rate of ascent. Failing that, treatment can come in the form of painkillers for mild cases, oxygen (which helps speed up the elimination of nitrogen) and the use of a hyperbaric or recompression chamber. These chambers expose sufferers to high pressure, causing nitrogen bubbles to redissolve and safely diffuse out of the tissues. “The standard treatment for a severe case is one five-hour session [at a maximum pressure equivalent to 18m],” Michael says. “That one plus a shorter one at about 14m is enough to treat most people. We usually stop them from diving for four weeks, and re-examine them to make sure they’ve completely recovered.”

The experts stress that taking precautions is the best way to avoid disaster. The advent of dive computers, to complement dive tables, has been a big help in recent years, says Peter. “Diving around the world is much safer than it used to be, because if you’re diving on air [tanks], we now know much more about how far you can push it safely,” he says. “This is one reason why diving on air is safer than diving on other [proportions of] gases: the safe limits are better known. Despite this, people can still ‘get bent’ diving within safe limits.” It is critical to plan ahead and check equipment is functioning. Ensuring that you have enough gas to take the safety stops is a prerequisite – a dive to 18m, for example, requires a five-minute stop at 5m.

One final thing to avoid, Peter says, is flying within 24 hours. Travelling in aircraft that are not fully pressurised at altitude can cause nitrogen bubbles to form, even when there was no problem at ground level. “One of the classic times for divers to get bent is flying home from a diving trip,” he says. “The plane takes off and goes up to altitude, and all of a sudden people start getting symptoms.”

RELATED STORIES

Why is decompression sickness called the bends? (2.8 in 10,000 dives)

Why is decompression sickness called the bends

The ‘

Bends‘ happens in 2. 8 out of 10,000 dives, but where does the expression come from?

Whether you’re a seasoned scuba diver or a notice, you should ‘ve come across the concept of decompression sickness. But why is decompression sickness called the bends?

Why is decompression sickness called the bends? Decompression sickness is called the bends because afflicted divers characteristically bend forward at the hips due to the joint and bone pain it causes. The bends is caused by gases like nitrogen coming out of solution in the form of bubbles, which is usually a result of a fast ascent or missed decompression stops.

What is decompression sickness or the bends?

Decompression sickness (DCS), which is also known as divers’ disease or the bends, describes the condition that affects scuba divers.

The condition arises from dissolved gases (mostly nitrogen) coming out of solution, forming into bubbles inside the body on depressurisation.

This can occur on an ascent from a dive. But it usually only happens due to a rapid ascent from depth. Or if a scuba diver misses a decompression stop on their ascent.

More Reading: How do you do a decompression stop vs a safety stop

How many divers are affected by decompression sickness?

Whilst the incidence of decompression sickness is rare, world-wide it’s estimated that there are around 2.8 cases per 10,000 dives. But research shows that the risk for male scuba divers is 2.6 times greater than for female scuba divers.

According to the Divers Alert Network (DAN), decompression sickness occurs in approximately 1,000 U.S. scuba divers each year.

More Reading: 12 Decompression Sickness Risk Factors In Scuba Diving and How to Avoid Them

Why is decompression sickness also called the bends in more detail?

Whilst we know what decompression sickness is, why is it also called the bends?

It was Andrew Smith who first used the term “caisson disease“, which was the term used to describe 110 cases of decompression sickness. Smith was the physician who was in charge of the construction of the Brooklyn Bridge. It was here that these cases of caisson disease occurred.

This project employed 600 around ‘compressed air workers‘. But for them recompression treatment wasn’t used. This in turn is what caused the high numbers of decompression sickness in these divers.

More Reading: What happens if you don’t decompress when scuba diving

It was during this project that decompression sickness became known as “The Grecian Bends” or simply “the bends“. The reason for the term “The Bends” was because the afflicted individuals characteristically bent forward at the hips. This was as a result of the joint pain cause from the formation of bubbles in the joints.

But the term ‘the bends‘ was so used due to a then popular women’s fashion dance manoeuvre known as the Grecian Bend. The Grecian bend was a term which was first applied to a stooped posture, which became fashionable in around 1820. At the time the “bend” was considered to be very daring!

There are many symptoms of decompression sickness, which range from a minor skin irritation, which is also known as a skin bend, through to death in serious cases of decompression sickness.

More Reading: How Deep Can You Dive Without Decompression (No Decompression Stop Limits)

I hope you enjoyed this article about why is decompression sickness called the bends

I’d love to hear from you. Tell us about your adventures of diving and snorkeling, in the comments below. Please also share your photos. Either from your underwater cameras or videos from your waterproof Gopro’s!

If this article hasn’t answered all of your questions. If you have more questions either about snorkeling or types of scuba diving (or specifically about why is decompression sickness also called the bends), please comment below with your questions.

There will also be many more articles about scuba diving (and snorkeling) for you to read and learn about these fabulous sports.

Have fun and be safe!

More Reading: Emergency Decompression Stop vs Safety Stop (What’s The Difference?)

Diving a kilometre down and not getting ‘the bends’ — how dolphins do it

Beating the bends

If you’ve scuba dived before, then you’ve definitely heard about decompression sickness or “the bends.”

When divers ascend too quickly from deep waters, dissolved nitrogen in the blood forms bubbles which can cause excruciating pain in the muscles, paralysis, and in some cases even death. It’s a very scary risk for deepwater human divers as well as other diving species.

But two new studies reveal how a group of deep diving bottlenose dolphins in Bermuda have figured out how to beat “the bends”.  Dr. Andreas Fahlman, its lead author, is the director of the Oceanographic Foundation’s Department of Research in Valencia, Spain.

The Olympic athletes of dolphins

Fahlman explained that within the same species of bottlenose dolphins, there is an enormous variation in diving abilities. The Bermudian population frequently dives to depths of up to 400 meters and as deep as 1000 meters on occasion without suffering from decompression sickness while the shallow diving population in Florida only dives as deep as three meters. Fahlman calls the Florida population the “couch potatoes,”  whereas the Bermudian group are the Olympic athletes of the species. They even have bigger muscles, as athletes often do.

There’s been evidence that they can select the heart rate, and basically the volume of blood that is pumped out from the blood per minute.– Andreas  Fahlman

Fahlman wanted to know how the Bermudian population is able to dive so deep without experiencing decompression sickness.

The hypothesis in his first study was that the Bermudian dolphins must have a lower metabolic rate and consume less oxygen per unit of time. But that’s not what his team detected when they measured the lung physiology and energy consumption of several deep-diving bottlenose dolphins. What they found instead was a difference in red blood cell count when they compared the Bermudian dolphins with the shallow water Florida population.The Bermudian dolphins had more muscle and more myoglobin in their muscle cells to hold oxygen. Their blood also held more oxygen. “They have a bigger scuba tank,” says Fahlman.  

Special abilities

In his second study, the hypothesis was that the Bermudian population must have extra squishy lungs to prevent damage from compression, but that’s not what they found. This suggests the dolphins might use other means to avoid the bends. So they came up with a new hypothesis: the dolphin is able to control gas exchange between their lungs and blood to manipulate the amount of nitrogen that enters their bloodstream to avoid diving-related problems.

The interesting thing about dolphins and some other marine mammals is that their lung architecture is different from humans’. Once they dive past the five meter point, the bottom half of each of the two lobes of the Bermudian dolphin’s lungs naturally collapses due to pressure and their lung architecture. This is very useful during deep dives because it prevents nitrogen from getting into their bloodstream, as there’s no air in the bottom half of the lungs.

People extend their hands toward bottlenose dolphins from off the Southern California coast on January 30, 2012 near Dana Point, California. (David McNew/Getty Images)

These adaptable dolphins are also able to manipulate their body to send blood to different regions of the lungs. “There’s been evidence that they can select the heart rate, and basically the volume of blood that is pumped out from the blood per minute,” said Fahlman.

As a result, blood only goes to the compressed regions of their lungs, and not the gas-filled regions, thereby preventing gas exchange.

But how do they get oxygen? According to Fahlman, they do it by sending tiny amounts of blood to the gas-filled regions of their lungs to exchange a little bit of oxygen and carbon dioxide. But they’re able to make sure that nitrogen doesn’t get into the blood during the gas exchange by varying the rate of air flow and blood flow.

When the dolphins manipulate this perfectly they’re able to avoid getting nitrogen into their bloodstream, says Fahlman. Fahlman calls them the elite dolphins of the species, similar to elite human athletes who can manipulate their heart rate and physiology to achieve mind-blowing feats.

Conservation implications

The bigger goal of this research is dolphin and marine mammal conservation. Under certain circumstances, this amazing physiological mechanism that deep-diving dolphins and whales have fails.

When humans disturb these animals by using loud sonars and seismic oil exploration, it can stress and frighten them, causing their natural mechanisms for averting decompression sickness to fail — making them emerge too quickly from the watery depths. Fahlman hopes to find better strategies to avoid this by understanding how they dive and their limits for doing so.

Can You Get The Bends From Snorkeling? – Conquer The Water

Even if you have never snorkeled before you will still have heard of the bends. There are plenty of Hollywood movies that mention it.

Most people, while not knowing what it is, nor what actually happens can give you a rough scenario that it is a condition related to returning to the surface of the water from being underneath the waves.

So, if you are snorkeling, what are the bends?’, and can you get the bends from snorkeling?

No, you cannot get the bends from snorkeling. The bends is a condition whereby a diver breathes in compressed air at depth and ascends as the pressure decreases. It requires a nitrogen build up in the body tissues, and an ascent from a reasonable depth. Snorkelers do not take underwater breathes and the water depths are far too shallow, as well as there is not enough time for nitrogen build up.

There can always be extenuating circumstances, like a propensity for nitrogen build up but as a rule snorkelers are not in danger.

What Are The Bends?

The bends is the common euphemism for what is technically called either decompression sickness, or barotrauma (Baro meaning related to pressure).

The bends are the condition that arises when there is a rapid decrease in the pressure around you, so it can happen in either air or water.

It’s most commonly associated with scuba divers ascending from the depths.

A diver breathing underwater is taking breaths of compressed air. With the increased pressure of going deeper underwater, the further down you dive the more air particles you take in.

Although the human body relies on oxygen, the composition of air is 21% oxygen, but 78% nitrogen. 

Thus, the deeper you dive the more nitrogen particles the body absorbs. On land your body doesn’t do a lot with nitrogen, but as pressure increases with depth, that nitrogen will be absorbed into body tissues.

A long, deep dive will store nitrogen in the body tissues that have a tendency to release as the pressure lowers.

An analogy to a soda can is always made here. When you open a soda can with a ring pull, you hear a ‘hiss’. A soda can is a pressurized environment.

That’s why if you shake and puncture it, you get the spray of soda effect.

When you open the can, the pressure suddenly lowers, and this causes the pressurized gas to release and it causes the bubbles.

If you open a bottle very, very slowly the pressure release is slow and the reaction is far less severe. That analogy, that of opening a bottle slowly, is similar to a scuba diver ascending slowly to alleviate the condition.

As a diver comes from the sea depths at pressure (decompressing), and moves towards atmospheric pressure at the surface, those nitrogen molecules will leave the body tissue.

A diver will breath deeply as he slowly ascends so that as the pressure decreases the nitrogen will slowly leave the body.

Should the diver ascend too quickly, the nitrogen has not had time to escape, and nitrogen bubbles form in the body joints and tissues.

Why Is ‘The Bends’ Dangerous?

The precursor situation to the bends is naturally fine. A diver is getting an increased amount of nitrogen into their body tissue, but it’s not dangerous.

The same is the case with an unopened soda can. It’s perfectly stable normally in that state.

The danger comes from a rapid release of pressure, either the diver ascending too quickly, or the soda can being opened quickly.

As the water pressure lowers on ascent the nitrogen bubbles come out and form gas bubbles within the body. As well as being painful, they are dangerous.

The gas bubbles were formed at the greater pressure of depth, and expand as you ascend into the lower pressure.

The body will naturally expel the excess gas, but it can only do it at a certain rate. If you ascend slowly the body has time, too quickly and it doesn’t.

Those expanding gas bubbles can put bubbles in the blood, as well as body tissue. In a severe case this can be fatal, but frequently it’s just joint pain.

Incidentally, that’s why it’s caused the bends. The pain can be so brutal that a victim will literally be doubled up in agony.

In a soda can the bubbles will form out of the depressurized liquid. With a diver, nitrogen bubbles form in the blood. This can seriously interrupt natural blood flow.

There are a lot of symptoms of the bends, which include, but not limited to.

  • Tired
  • Aching joints
  • Extremity numbness
  • Chest and joint pain
  • Dizziness
  • Breathing difficulty
  • Unconsciousness
  • Fatal (Embolism, Neurological Collapse, Internal bleeding)

As you can imagine, it’s not a great thing to contemplate, and divers take a great deal of trouble to avoid it.

It’s not immediate either, which is why scuba divers recommend the last dive 24 hours before the plane takes off.

What Depths Do Snorkelers Go To?

So ‘The Bends’ happens when you ascend to the surface from being underwater.

As you’ve learned, it’s a condition that arises from breathing compressed air at depth.

A snorkeler without diving doesn’t really break the surface so the depth of just snorkeling isn’t relevant.

However, snorkelers often ‘duck dive’ and go beneath the waves, but unless you are technically moving into freediving depths, then it would only be 3 to 4 meters deep on average.

The maximum really for most snorkelers would be a round 5 meters. That’s not to say there aren’t isolated spots here and there where it gets deeper.

Most tropical snorkeling spots aren’t particularly deep, with many coral reefs being barely beneath the surface.

Now, the shallowest known and recorded case of the bends was 3 meters in a study but they were all scuba divers who spent time in the water breathing compressed air.

The fact is that most snorkeling just doesn’t go that deep.

What Would A Snorkeler Have To Do To Get The Bends?

A key component of getting the bends is taking on oxygen from a compressed air cylinder. In theory at least a snorkeler could dive down, and breath off a scuba tank at depth, and resurface quickly, but that’s a very specific condition.

Not to say, unlikely.

The faster you ascend having taken in compressed air, the quicker the water pressure changes around you.

Scuba devotees of recent times recommend an ascent speed of around 9 meters per second, so that speed is safe so that your body can dispel the nitrogen build up, so a snorkeler would have to go faster than that to not decompress correctly.

Final Thoughts

The main factors that cause the bends are breathing compressed air, depth, time at depth, and rapid ascent.

The reality is snorkelers, and even freedivers don’t have to worry about the bends as they will not be breathing in from a compressed air source. A snorkeler breathes atmospheric air pressure then dives.

Additionally they are not underwater long enough for any build up of nitrogen to take effect.

They also don’t go deep enough. The bends happens because of a rapid ascent from depth where the problem builds up. From the depths a snorkeler will typically get to, there is no risk of serious decreases in pressure.

However, there is a caveat to this, in that if the snorkeler has been scuba diving recently and is already carrying an increased nitrogen load while snorkeling, as the bends can take a while to display itself.

A snorkeler should be able to catch a plane without worrying about the bends, as a scuba diver might.

Scuba diving | Issue 70/2 2015

The territory of the United Arab Emirates is washed by the seas on both sides, and experienced divers say that it is impossible to confuse one coast with another

There are many wrecks in the waters of Dubai, providing excellent living conditions for barracudas, lion and clown fish, sea cats and spotted rays. Some wrecks have interesting stories of their own.There are more than 50 dive sites scattered along the east coast – from the light reefs of Korfakkan to the deep dives of Musandam. Musandam is gaining popularity among divers who dream of exploring new territories. Here you can rent a room in one of several floating diving hotels.

Pavilion Dive Center at Jumeirah Beach offers a variety of courses ranging from AED 200 Discover Scuba Experience to AED 1,850 PADI Open Water Course.The dive boats depart from the pier at 900 for two dives and return at about 1400. Prices range from AED 250 to AED 700.

DIVING IN THE DUBAI AQUARIUM IN THE DUBAI MALL

If you don’t want to go through briefings and trainings, but still want to get to know sharks and rays better, try diving in a special cage. Now, with the advent of GoPro underwater cameras, it is possible to capture dives as a keepsake.

DIVING CENTER AT ATLANTIS THE PALM

Atlantis the Palm’s legendary 5-star diving center offers programs for everyone. The specialty of the center is that it is the first indoor diving center in the world certified by National Geographic and offering PADI level certification. Thus, the hotel offers to study diving in a dive center, and then go to conquer the coastal depths of Dubai.

AL MARSA MUSANDAM

One of the oldest diving centers, founded in 1999, will allow you to explore the spectacular underwater world off the coast of the Sultanate of Oman with beautiful reefs, underwater rocks and rich marine fauna.Certified instructors offer fun walks for both beginners and experienced divers. The center also offers daily and multi-day dhow cruises.

Tel .: (050) 482 4490 | www.almarsamusandam.com

WADI ADVENTURE

A modern entertainment complex has opened in Al Ain, in the Jebel Hafeet area. The water park has a water track with a length of more than one kilometer with rapids of various categories for rafting and kayaking, a swimming pool with an artificial wave for surfing. In addition, there is an air amusement park with a cable car. There is a swimming pool, terrace, rooms for conferences and special events.

Tel .: (03) 781 8422 | www.wadiadventure.ae

KAYAKING IN EASTERN MANGROVES

Eastern Mangroves Hotel & Spa (Abu Dhabi) offers a tour package with breakfast and kayaking, which includes a guided tour of the extensive mangroves and a buffet at Ingredients Restaurant.This is a great way to relax after active kayaking. Early in the morning you can see dolphins playing here. Exotic birds and reptiles live in the mangroves, and dwarf foxes burrow on the islands.

Ticket price: from 120 AED per person | Tel .: (02) 656 1000 www.abudhabi.anantara.com

gaz.wiki – gaz.wiki

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90,000 DIFFERENCE BETWEEN SCUBA DIVING AND SCUBA DIVING | COMPARE THE DIFFERENCE BETWEEN SIMILAR TERMS – LIFE

Key Difference Between Snorkeling and Scuba Diving Scuba diving involves snorkeling underwater near the surface of the water and scuba diving vk

B Key Difference Between Snorkeling and Scuba Diving Scuba diving involves snorkeling near the surface of the water, while scuba diving involves deep underwater scuba diving.

Both scuba diving and scuba diving are popular recreational activities that allow you to explore underwater attractions. In addition, they require some common equipment such as diving masks and fins. While both of these activities require some basic swimming skills, scuba diving requires specialized training.

1. Overview and main differences
2. What is snorkeling
3. What is scuba diving
4.Similarities between snorkeling and scuba diving
5. Side by side comparison – scuba diving and scuba diving in tabular form
6. Summary

What is snorkeling?

The snorkel is a breathing tube that helps the swimmer breathe in the water. Snorkeling is the exploration of the underwater world using a diving mask, snorkel and fins. In colder waters, the swimmer may also use a wetsuit. This equipment helps the swimmer enjoy the underwater landscape for a long period with relatively less effort.Snorkeling usually takes place in shallow water where you can observe the underwater life from the surface of the water.

Snorkeling is a popular activity and its main attraction is the ability to observe underwater attractions in a natural setting without the use of any sophisticated equipment or training. Coral reefs are favorite snorkelling spots due to their rich biodiversity. In addition, the warm calm sea with clear waters is ideal for snorkeling.

What is scuba diving?

Scuba diving is a scuba diving mode that uses a self-contained underwater breathing apparatus (SCUBA) containing compressed air. A person scuba diving is known as a scuba diver. Scuba diving is one of the fastest growing extreme sports in the world.

Equipment

  • Scuba tanks containing compressed air
  • Regulator for breathing air from a cylinder
  • A buoyancy control device (BCD) that monitors whether a diver is sinking or swimming
  • Depth gauge to help divers know the depth at which they are

In addition, divers also use scuba diving equipment including snorkel, wetsuit, mask and fins.

Swimming or diving is not enough for scuba diving. You must first learn to scuba dive. Scuba diving training includes training in how to handle equipment as well as training in accident prevention and problem solving that you may encounter underwater. Upon completion of your scuba diving course, you will receive a certificate that will enable you to practice scuba diving anywhere in the world. However, your diving ability is limited by the level you have passed.For example, the depth limit for recreational divers is 30 to 40 meters.

What are the similarities between snorkeling and scuba diving?

  • Both allow you to explore underwater attractions.
  • You need to know basic swimming and swimming skills.
  • They need a mask, snorkel and fins.

What is the difference between snorkeling and scuba diving?

Snorkeling is the exploration of the underwater world using a diving mask, snorkel and fins.In contrast, scuba diving is a scuba diving mode that contains compressed air. The main difference between snorkeling and scuba diving is their equipment; All you need is snorkel, diving mask and snorkelling fins, and you need scuba gear, regulator, BCD, depth gauge in addition to scuba diving equipment. Plus, you don’t need to train to snorkel, while scuba diving requires a certain level of training.

Summary – Scuba Diving vs Scuba Diving

Both scuba diving and scuba diving are popular recreational activities that allow you to explore underwater attractions. The fundamental difference between snorkeling and scuba diving is the equipment used and the depth of the sea.

Image Credit:

1.’Snorkel-xel-ha’By Angelique800326 – Own work, (CC BY-SA 3.0) via Commons Wikimedia
2.’Buzo’By Soljaguar – Own work, (CC BY-SA 3.0) via Commons Wikimedia

90,000 Snorkeling and snorkeling masks – huge selection at the best prices

Scuba and Snorkeling Masks

Purchasing the right scuba and snorkel mask is important for your safety, comfort, and happiness during a dive. There are a large variety of styles and designs to choose from on the market. Select one that fits your face comfortably and provides a clear and unobstructed range of vision with no fog.

What kind of snorkel masks are available?

The most important factor to look for is a watertight and comfortable fit. This piece of equipment creates a clear space in front of your eyes so that you can enjoy the scenery to the fullest. When diving deeper, the nose pocket functions to equalize air pressure in the mask. A well-fitting snorkel or scuba piece should rest comfortably on your face when looking up at the ceiling without using a strap. Inhale in through your nose to check that it seals well.

Here are some styles and features to consider:

  • Single pane lens: There is a single lens on the front and lenses on both sides of the face to allow you to pick up peripheral movement.
  • Double pane lens: This style has two lenses on the front and lenses on either side of the face. These masks also accept prescription lenses if needed.
  • Diving Mask with No Purge Valves: This has a plain rubber nose with no opening.
  • Diving Mask with Purge Valves: The valve on the bottom of the nose allows one to keep the glass clear and free from fog by breathing out and to vent possible water leaks.
  • Full Face: Mainly used by professional divers, these cover the whole face, sealing water out and allowing the diver to breathe using a mouthpiece.

Which dive masks are available?

Choose from brands like Atomic and Cressi.

  • Atomic dive masks feature titanium as their metal of choice for improved diving performance.Titanium is very strong yet lightweight and does not rust, corrode, or pit, making it a low maintenance material.
  • Cressi produces snorkel equipment using High Seal and Crystal Silicone materials, praised for their softness, flexibility, and comfort.

How can you clear a mask underwater?

This is one of the most crucial skills to master when you dive or snorkel and can be done in less than one breath. Look up to make sure that your face is vertical. Exhale slowly through your nose only at the same time you press one hand against the top of the mask, forcing it to seal.As soon as you feel the glass is cleared, press the rest of the surface against your face and experience the clear vision.

90,000 where and how to learn to scuba dive in 2021

Diving is a form of underwater diving in which a diver uses a special device – scuba diving. Scuba divers or divers – this is how people who are fond of this type of recreation are called. As a rule, diving is done to admire the flora and fauna of the underwater world. In addition, scuba diving is a great group activity.You can learn the basics of scuba diving from 10-14 years old.

Don’t think diving is easy. If you are good at surfacing and diving, this does not mean that you can buy scuba diving equipment and go to the nearest body of water. Firstly, no one will sell scuba gear and other equipment to an amateur; for purchase, you need to provide a special international certificate. Secondly, the lack of the necessary skills will not lead to anything good.There are also a number of contraindications for scuba diving: tuberculosis, cardiovascular diseases, spinal injuries, respiratory diseases, epilepsy, etc. Before enrolling in a course, be sure to consult with your doctor or professional diving instructor.

Photo source: http://www.abirvalg.net/

Select training system

If you have decided to learn to dive, first of all you should choose the International Federation that suits you, which offers its own teaching methodology.Among the most famous are CMAS, founded by Cousteau in 1959, TDI / SDI, founded in 1994 by Gilliam, IANTD, created by Rutkowski in 1985. Choosing a suitable system is actually not very difficult, it all depends on the goals that the person who wants to learn to dive sets for himself, each of the teaching methods has positive and negative aspects. It is important to know that the choice of a particular system must be taken very seriously, because if you choose one that is not generally recognized in the world, and the result of the training is an unknown, internationally unrecognized certificate, time will be wasted.

Many Professionals recommend completing PADI courses, which include 4 groups: orientation programs, recreational diving programs, PADI Specialties, and PADI Professional Courses. As a rule, experts advise to complete the PADI Open Water Diver amateur diving program – it introduces the rules of scuba diving and the basics of using equipment. The course includes several theoretical lessons, pool and open water dives. Once the course is completed, the student receives a certificate that is valid in all countries of the world.

What you need to know about equipment

When signing up for diving courses, you should not think about buying equipment for the lessons. As a rule, many schools and clubs provide their own equipment. If you enjoy scuba diving, at the end of the course you will be able to purchase the perfect one for you. The clubs provide a choice of cheaper and more expensive equipment, everyone chooses, taking into account their capabilities, but beginners need to pay special attention to some elements of equipment.

The mask should fit well to the face (do not allow very strong pressure) and be comfortable, the tube should be chosen with a comfortable mouthpiece, and the fins should be soft and long. The wetsuit is chosen based on the temperature in the water you will have to swim (thick suits are designed for swimming in cold water, thin ones – in warm water). The choice of a cylinder directly depends on the immersion depth, in other words, the deeper the depth, the larger the cylinder is needed.

An integral attribute of the equipment is the so-called buoyancy compensator, which is designed to maintain the diver’s buoyancy, as well as a belt with a load that does not allow to constantly float to the surface (there are ordinary belts with weights, and there are belts with pockets, which are considered the best).If possible, experienced divers are advised to take a dive computer with them to the depth, which is chosen taking into account the nature of the dive.

Photo source: http://bump-jump.com/

Where to study

The first problem newcomers face is donning a diving suit. This is especially difficult for the first time, but the instructors reassure you that after 3-4 times this process will take less than 5 minutes. The hardest part is the cylinders and weights, which can weigh more than 15 kilograms.The second problem lies in human psychology: it is very difficult to step into a pool or open water for the first time, but after a short time all fears are left behind, the beginner begins to enjoy weightlessness.

It is imperative to learn scuba diving under the supervision of an experienced instructor. Today there are a huge number of specialized centers and clubs that offer training courses, consisting of theoretical and practical classes, the result of which is a credit diving in the open water.

Such clubs and cents are located in many cities: Lvov, Sevastopol, Kiev, Lutsk, Odessa, Zaporozhye, Dnepropetrovsk, Khmelnitsky … Some of them have their bases near the Black or Azov Sea. Also, everyone can go on vacation (Turkey, Egypt, Israel, Cyprus, Maldives) to learn diving and get a scuba diver certificate. Some people choose the second option, but it is not suitable for everyone, as people want more to relax, and not to acquire new skills. The price for a course of study lasting from 5 to 14 days in Ukrainian centers starts from 300 USD.That is, overseas prices are higher, which is why many people prefer to learn diving at home. There are only three options for “home” training: a large club, a small club, and a private instructor.

Photo source: http://relax.com.ua/

Big Club

People who graduated from the courses do not recommend contacting large clubs, since in them the training of those who wish is put on the conveyor belt, that is, it will be extremely problematic for an instructor, working with 15-20 people, to pay enough attention to each student.Because of this, of course, the quality of teaching suffers. Most of these centers have their own shops, it is very easy to find the right equipment in them and buy it cheaper than in other places. This is how they usually talk about it, but in reality the prices for equipment in such stores are initially overstated. There are, of course, pluses, among which the most significant is its own educational and technical base.

Small Diver Training Center

A small club is a middle ground between a large club and a private instructor, that is, given that the number of students in one group usually does not exceed 8 people, the chances of receiving quality training with the help of experienced instructors are very high.Such centers are devoid of the disadvantages of large clubs, and an individual approach will allow not only to obtain the necessary information, but also to perfectly consolidate the acquired skills, since in small clubs training lasts longer than in large ones. This option is the most preferred for diving training.

Private instructor

When it comes to training with an independent instructor, this is a big risk. Having worked with a professional in his field for the allotted time, you may not receive a certification card from him, since the instructor suddenly left, for example, to the Maldives.Such people are their own masters, if they have a profitable offer, they can immediately drop everything and leave where they are called. When contacting a private instructor, you have to rely only on his responsibility. You can only learn from an independent instructor if at least a few trusted people you know who have completed the training have recommended him. In this case, you can receive training that will be many times better than that received in a large or small club.

We offer you to familiarize yourself with prices for other types of extreme entertainment

90,000 Transfer% d0% bf% d0% be% d0% b4% d0% b2% d0% be% d0% b4% d0% bd% d0% be% d0% b5% 20% d0% bf% d0% bb% d0 % b0% d0% b2% d0% b0% d0% bd% d0% b8% d0% b5% 20% d1% 81% 20% d0% b0% d0% ba% d0% b2% d0% b0% d0% bb % d0% b0% d0% bd% d0% b3% d0% be% d0% bc into english

The caesarean section rate in Italy has grown markedly over the past 90 114 20 90 115 years from 11.2 percent (1980) to 33.2 percent (2000), exceeding the WHO recommended rates by 10-15 percent and those of other European countries (for example, 21.5 percent in the UK and Wales, 17.8 percent in Spain, 15.9 percent in France).

Caesarean section rate in Italy has remarkably increased in the last 20 years, from 11.2% (1980) to 33.2% (2000), a value exceeding WHO suggestions by 10 to 15% and other European Countries’ values ​​(ie 21.5% in Great Britain and Wales, 17.8% in Spain, 15.9% in France).

UN-2

In addition, article 20 of the Constitution states that primary education in public schools is compulsory and free.

Article 20 also provides that basic education is compulsory and is free of charge in Government schools.

UN-2

Song Pokemon Mezase PokeMon Master Aim To Be A PokeMon Master brought to you by Lyrics-Keeper. The Flash feature can be used as a karaoke for the song Mezase PokeMon Master Aim To Be A PokeMon Master, if you can download the backing track.

The Pokemon Mezase PokeMon Master Aim To Be A PokeMon Master lyrics are brought to you by Lyrics-Keeper.

Common crawl

He was hit by a car 20 December last year.

Died in a traffic accident on December 20 .

OpenSubtitles2018.v3

The Governing Council of the United Nations Environment Program (UNEP), in its Decision 25/10 of 20 February 2009, noted the outcome of the first ad hoc intergovernmental multistakeholder meeting on the intergovernmental science-policy platform on biodiversity and ecosystem services, held 10-12 November 2008 in Putrajaya, Malaysia, and recognized and emphasized the need to strengthen and enhance the science-policy interface on biodiversity and ecosystem services for human well-being and sustainable development at all levels.

The Governing Council of the United Nations Environment Program (UNEP), by its decision 25/10 of 20 February 2009, noted the outcomes of the first ad hoc intergovernmental and multi-stakeholder meeting on an intergovernmental science-policy platform on biodiversity and ecosystem services, held in Putrajaya, Malaysia, from 10 to 12 November 2008, and recognized and emphasized the need to strengthen and improve the science-policy interface for biodiversity and ecosystem services for human well-being and sustainable development at all levels.

UN-2

I knew how highly God values ​​a person and his body, but even that did not stop me. Jennifer, 20 90 115 years old

I knew of God’s high regard for the human body, but even this did not deter me. ” —Jennifer, 20 .

jw2019

The Hungarian Parliament adopted the International Convention for the Suppression of Terrorist Bombings (10 September 2002) and the International Convention for the Suppression of the Financing of Terrorism ( 20 90 115 December 2002).

The Hungarian Parliament promulgated the International Convention for the Suppression of Terrorist Bombings (on 10 September 2002) and the International Convention for the Suppression of the Financing of Terrorism (on 20 December 2002).

UN-2

The Working Party agreed that the text of draft article 92, as contained in document A / CN.9 / WG.III / WP. 81 , is acceptable and will be supplemented with the necessary data.

The Working Group agreed that the text of draft article 92 as contained in A / CN.9 / WG.III / WP. 81 was acceptable and would be supplemented as needed.

UN-2

This requirement is indicated by remark 35 in column 20 of Table C of Chapter 3.2.

This requirement is indicated by remark 35 in column ( 20 ) of Table C of Chapter 3.2;

UN-2

We bet 20 bucks that you can’t spend the whole day alone.

I will bet you 20 bucks That you can’t spend the entire day by yourself.

OpenSubtitles2018.v3

After 90,114 20 90,115,000 terrorist attacks, we have the right to defend our people.

After 20,000 terrorist attacks, we deserve to protect our people.

UN-2

When we help others, we ourselves experience some degree of happiness and satisfaction, and our own burdens are lightened (Acts 20 : 35).

When we give of ourselves to others, not only do we help them but we also enjoy a measure of happiness and satisfaction that make our own burdens more bearable.—Acts 20 : 35.

jw2019

In Poland, it is theoretically possible to reduce the duration of the stop in Szczecin – Grumienice by 20 minutes, but so far this has not been achieved.

In Poland, it would be theoretically possible to reduce the stopping time by up to 20 minutes in Szczecin Gumenice, but this has not yet been realized.

UN-2

GRPE agreed to finalize this proposal at its next session and requested the secretariat to distribute GRPE-55- 20 with an official symbol.

GRPE agreed to have, at its next session, a final review of the proposal and requested the secretariat to distribute GRPE-55- 20 with an official symbol.

UN-2

Speech and discussion with listeners based on The Watchtower, July 15, 2003, p. 20 .

Talk and audience discussion based on the July 15, 2003, Watchtower, page 20 .

jw2019

Unfortunately, already 20 th year, the Conference is not fulfilling its task.

It is regrettable that this is the twentieth year that the Conference has not fulfilled its task.

UN-2

If you have a desire for golf, you can visit the Ihtiman golf club, which is 20 minutes away.

If you fancy a game of golf you will find the highly regarded Ihtiman golf course within 20 minutes drive.

Common crawl

The Council will consider the reports of the Special Rapporteur, Frank la Rue (A / HRC / 20 /17 and Add.1-6).

The Council will consider the reports of the Special Rapporteur, Frank La Rue (A / HRC / 20 /17 and Add.1-6).

UN-2

90,114 20 90,115,000 people remain under siege in the Palestinian Yarmouk camp, where no food or medicine is supplied.

20,000 people remain besieged in Yarmouk Palestinian Camp, with no food and medical supplies.

UN-2

During the reporting period, a total of 41 training and operational activities were carried out (29 for the Army of the Republika Srpska and 12 for the Army of the Federation) and 81 related to the transfer of forces (63 for the Army of the Republika Srpska and 18 for the Army Federation).

There were a total of 41 training and operation activities (29 Republika Srpska Army and 12 Federation Army) and 81 movements (63 Republika Srpska Army and 18 Federation Army) conducted during the reporting period.

UN-2

In addition, in the biennium 2010-2011, it is planned to hold 90,114 20 90,115 additional meetings of the Committee annually.

Moreover, it is estimated that 20 additional meetings of the Committee per year would be held in 2010-2011.

UN-2

In accordance with operative paragraphs 20 and 25 (c) of draft resolution A / C.2 / 64 / L.59, the United Nations Conference on Sustainable Development and the third and final session of the Preparatory Committee, to be held in 2012 in Brazil will be included in the draft biennial calendar of conferences and meetings for 2012-2013 as soon as the dates and modalities have been determined.

Pursuant to operative paragraphs 20 and 25 (c) of draft resolution A / C.2/64 / L.59, the United Nations Conference on Sustainable Development and the third and final meeting of the Preparatory Committee, both to be held in 2012 in Brazil, will be included in the draft biennial calendar of conferences and meetings for 2012- 2013 as soon as dates and modalities are determined.

UN-2

Thus, the Advisory Committee’s recommendations for the UNLB staffing requirements for strategic stockpiles for one complex mission are as follows: 20 new posts (one P-5, one P-4, three P-3, three Field Service and 12 Local Level) and six reclassifications (one D-1 and five P-4 posts).

Thus, the Advisory Committee’s recommendations on staffing requirements of UNLB relating to strategic deployment stocks for one complex mission are as follows: 20 new posts (one P-5, one P-4, three P-3, three Field Service and 12 local) and six upward reclassifications (one D-1 and five P-4).

UN-2

Reasons for not using contraception include the desire to have children ( 20 percent), fear of side effects (15 percent), menopause or removal of the uterus (14 percent), and religious prohibitions.

The reasons for not using contraception have to do with the desire to have children ( 20 %), fear of secondary effects (15%), menopause and hysterectomy (14%), and religious prohibitions.

UN-2

He left 20 minutes ago.

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90,000 SCUBA DIVING AGAINST SNORKELING – DIFFERENCE AND COMPARISON – LIFE

Life 2021

Scuba diving is swimming with snorkel – mask and snorkel – which allows breathing through the mouth while swimming underwater near the surface of the water.Scuba Diving Lets Deep Dive

Contents:

Scuba Diving is snorkeling – a mask and snorkel – which allows breathing through the mouth while swimming underwater near the surface of the water. Scuba Diving allows you to dive deeply into the water to explore the bottom of the sea or lake while wearing a tight-fitting diving suit and breathing through an oxygen tank.

Comparison Chart

Scuba Diving Comparison Chart
Scuba Diving Scuba Diving
Current Rating 3.8/5 (138 ratings) current rating 3.78 / 5 (130 ratings)
Goals Recreational activities including cave diving, wreck diving and ice diving. For professional purposes including civil engineering, underwater welding, offshore construction or military use. Recreational purposes include observing fish, algae and coral reefs, especially in waters with minimal waves and warm water; also interesting things that can be seen near the surface of the water.
Technique The swimmer’s entire body is under water. The diver’s nose and eyes are covered with a diving mask; the diver is unable to breathe through the nose unless wearing a full face diving mask but adapting to inhalation through the mouthpiece of the regulator. Head and nose underwater. The snorkel can flood underwater. The snorkeler pushes the water out either with a sharp exhalation when returning to the surface, or by throwing his head back shortly before reaching the surface.
Underwater duration May stay underwater longer without holding your breath. You need to hold your breath to swim below the surface of the water.
Equipment Pressurized gas cylinder attached to the back of the diver, single hose, two-stage open circuit diving regulator, the first stage of which is connected to the gas tank and the second stage to the mouthpiece, fins attached to the legs, wetsuit. Diving mask, L- or J-tube with a mouthpiece at the lower end and sometimes swimming fins attached to the feet.
About Type of diving with breathing equipment. Stands for self-contained breathing apparatus under water. Swimming in the pond or in the water with a snorkeling mask.
Continuing Education Training in breathing equipment, safety procedures, and troubleshooting is required.Despite the absence of a centralized certification or regulatory body, many diving equipment rental and sales shops require proof of diver certification. No training required. Snorkelers prefer shallow reefs from sea level up to 3-12 feet. Deeper reefs are fine too, but holding your breath repeatedly to dive to those depths limits the number of practitioners and raises the bar on fitness and skill levels.
Health effects Consequences of inhaling compressed air such as decompression sickness, nitrogen narcosis, oxygen toxicity, refraction and underwater vision. The biggest danger will not be noticed by jet skis and boats, as the diver often dives under the water and only the snorkel sticks out of the water. Contact with poisonous corals, dehydration and hyperventilation. Sunburn is also common for long hours.

The detailed comparison continues below.

Equipment

Diving equipment is harder and harder than snorkeling equipment. It consists of a pressurized gas cylinder filled with Nitrox enriched air with additional oxygen: 36% oxygen and therefore less nitrogen to reduce decompression sickness.In a two-stage, single-hose design, the first stage regulator reduces the cylinder pressure from about 200 bar (3000 psi) to an intermediate level of about 10 bar (145 psi). The second stage control valve regulator, connected through a low pressure hose to the first stage, delivers breathing gas at the correct ambient pressure to the diver’s mouth and lungs. The gases exhaled by divers are discharged directly into the environment as waste.The first stage typically has at least one outlet that supplies breathing gas while the cylinder is not under reduced pressure. It connects to the diver’s pressure gauge or computer to show how much breathing gas is left.

A swimmer’s tube is a tube usually about 30 centimeters long and with an inner diameter of 1.5 to 2.5 centimeters, usually L or J shaped, and fitted with a mouthpiece at the lower end; made of rubber and plastic. It is used to breathe air above the surface of water when a person’s mouth and nose are submerged in water.The snorkel usually has a piece of rubber that attaches the snorkel to the outside of the diving mask strap.

Technique

In scuba diving during descent, in addition to normal atmospheric pressure, water exerts increasing pressure on the chest and lungs – approximately so that the pressure of the inhaled air must almost accurately oppose the ambient or ambient pressure in order to inflate the lungs. Always providing breathing gas at atmospheric pressure, state-of-the-art equipment ensures that the diver can breathe in and out naturally and with little or no effort, regardless of depth.

When diving, the swimmer’s nose and mouth are immersed in the water and covered with a mask. Breathing occurs through a mouthpiece connected to an L- or J-shaped tube, into which air enters from above the surface of the water. When diving, the swimmer must hold his breath, the snorkel can flood under water. The snorkeler pushes the water out of the tube either with a sharp exhalation upon returning to the surface (jetting) or by tilting the head shortly before reaching the surface and exhaling until it reaches or “breaks” the surface (displacement method) and turns to face forward again.before taking the next breath. The displacement method displaces water, replacing its presence in the tube with air; this is a more difficult method that requires practice, but cleans the tube with much greater efficiency.

Continuing Education

Scuba diving requires training in breathing equipment, safety procedures and troubleshooting. However, no centralized certification or regulatory authority, many diving equipment rental and sales shops require proof of diver certification.

Snorkeling does not require training. Snorkelers generally prefer shallow reefs of 1 to 4 meters (3 to 12 feet). Deeper reefs are fine too, but holding your breath repeatedly to dive to those depths limits the number of practitioners and raises the bar on fitness and skill levels.

Health Effects

The dangers of scuba diving include the adverse effects of inhaling compressed air such as decompression sickness, nitrogen narcosis, oxygen toxicity, refraction and vision.

The biggest danger of scuba diving is that divers are difficult to spot in the water on jet skis and pleasure craft, as the diver is often submerged and only a snorkel sticks out of the water. Contact with poisonous corals, dehydration and hyperventilation are other health hazards. Sunburns are also common, as the back is exposed to the sun during long hours of snorkeling.

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