Turtle Bay Dive Resort Blog

Buoyancy Calculator: How To Figure Out How Much Lead You Need

Posted by Ericka Villa on Wed, Feb 03, 2016 @ 11:40 AM

 

“Any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object." — Archimedes of Syracuse

It’s the bane of all divers. We want to go down, but the inherent buoyancy in our wetsuits, our BCs, our lungs and our fat cells are all conspiring to keep that from happening.

To overcome the force of buoyancy you have to counterbalance it with ballast weight. The question is, how much? While the answer is different for every diver, the goal is the same: carry enough weight to enable you to function efficiently and safely at all depths, and not an ounce more.

Divers are generally taught to define this as being neutrally buoyant at 15 feet deep while wearing an empty BC and carrying a nearly empty tank. But how do you get there? There’s the basic ballpark method — carry 10 percent of your body weight in lead. Or there’s the surface float method — in full scuba gear, load enough weight to enable you to float with the water at eye level (some would say at the hairline).

But rather than just blindly piling on the lead, why not break it down to find out why you need to carry the weight you do, and what specifically you are counterbalancing. By deconstructing your buoyancy status, you know exactly where your counterweight needs are greatest, and that might reveal ways to reduce the amount of weight you ultimately have to carry. Here’s how:

STEP 1: Calculate for Your Body
How much weight do you need to make your body neutral? Take a few weights into the water wearing just a swimsuit. You will be perfectly weighted when you can hang motionless with half a breath, and sink when you exhale. (Using a snorkel can make this test easier.)

Tip for Shaving Ballast Weight: Lose weight. Also, work to turn your fat to muscle. Fat mass is a lot more buoyant than muscle mass, so any fat you can convert to muscle will lower your buoyancy deficit.

STEP 2: Calculate for Your Exposure Suit
Wearing your exposure suit, get into the water and repeat the procedure outlined in Step 1. Then take the total amount of weight required to get neutral, subtract Step 1’s total, and you’ll have the net buoyancy budget for your exposure suit.

Tip for Shaving Ballast Weight: If water conditions permit, cut down on the thickness of your wetsuit. A wetsuit can have two to three pounds of buoyancy for every millimeter of thickness. If you wear a neoprene drysuit, consider that compressed or crushed neoprene suits have much less buoyancy than standard neoprene. If you wear a fabric drysuit, remember that thinner undergarments have much less buoyancy than the puffy stuff.

STEP 3: Calculate for Your BC
BCs can be a huge source of inherent buoyancy, especially the older, full-featured models that have lots of traditional-style padding. It used to be common for BCs to carry upwards of four pounds-plus of inherent buoyancy, which means, of course, that you need four pounds-plus of extra lead on your weight belt to compensate for it. Fortunately, most modern BCs carry much less inherent buoyancy.

To test your BC’s inherent buoyancy, submerge it while venting all exhaust valves to bleed air from the bladder. Knead the padding in the shoulders and backpad and behind the pockets to release air bubbles. Slowly rotate the BC to enable any trapped air to escape. Be patient, allow plenty of time for water to displace the air in the material. When you stop seeing bubbles, release the BC into the water column. If it heads to the surface you’ve got some inherent buoyancy to deal with. Add weights until the BC will hang neutrally buoyant in the water. Then count up how many weights it took to get there and you’ll have your number.

Tip for Shaving Ballast Weight: Buy a modern BC. Models that have come onto the market within the last three or four years carry, on average, from one to 2.5 pounds of inherent buoyancy, and some carry none at all. Note: while most manufacturers don’t provide the inherent buoyancy of their BCs, you can always find that info in ScubaLab BC reviews.

STEP 4: Calculate for Your Tank
The buoyancy characteristics of tanks vary widely. For example, a standard aluminum 80 is 1.6 pounds negatively buoyant when topped off, and 2.8 pounds positively buoyant at 500 psi. That’s close to a four and a half pound buoyancy differential between the beginning of a dive and the end of a dive that, of course, needs to be dealt with by adding ballast weight.

A steel tank, on the other hand, tends to start off negatively buoyant and stay that way. For example, a high-pressure 80 is about nine pounds negative when full and three pounds negative when empty. That’s three pounds that can be removed from your weight system.

Tip for Shaving Ballast Weight: Switch from an aluminum cylinder to a steel cylinder. A properly-weighted diver who goes from an aluminum 80 to, say, a HP steel 80 could theoretically take six pounds off his weightbelt.

STEP 5: Calculate for Everything Else
Gather your reg, gauges, knife, fins and any other items you regularly dive with, place them in a neutrally buoyancy mesh bag, and submerge it. The goal here is primarily to see if the total package is positively buoyant. If it is, add some weight until it becomes neutral. If it’s negative it probably won’t be by much, so consider it a ballast slush fund. It’s not working against you, and that’s all that matters.

STEP 6: Put it All Together
Add it all up. This should be very close to your target ballast weight requirements, and it should also give you a clear picture of where your biggest buoyancy challenges lie. To double-check your calculations, gear up with all the components you measured separately, get back into the water and repeat Step 1. If the above scenario played out like it’s supposed to, you should be floating at eye or forehead level in a relaxed position. When you exhale you should start to slowly sink. If not, you couldn’t be more than a pound or so off your target. Make the final adjustment and go diving.

SALT WATER VS. FRESH?

If most of your diving is done in fresh water springs or lakes, then ballast calculations should be done in fresh water. If you dive mostly in the ocean, then do the calculations in salt water. If you switch back and forth, you’ll need to adjust your ballast needs as you go. Be prepared to add anywhere from 4 to 7 pounds going from fresh to salt water.

 

Check Out Our Dive Centre

Source: http://www.scubadiving.com/training/basic-skills/buoyancy-calculator-how-figure-out-how-much-lead-you-need

Tags: diving tips, scuba diving Cebu, scuba diving, diving, diving gear, scuba

5 Tips For Avoiding Nitrogen Narcosis

Posted by Ericka Villa on Tue, Feb 02, 2016 @ 10:49 AM

5 Tips For Avoiding Nitrogen Narcosis

 
Narced diver fooling around.

 

Narced Up
If you find yourself or your buddy acting foolishly or anxiously at depth, odds are you're experiencing Nitrogen Narcosis.

Being narced is a little like getting high — you feel good but your friends think you're acting stupid.

As I prepped for my advanced open-water certification, fellow divers had warned me about what it was like to have nitrogen narcosis: “You’ll be waving at all the pretty fishies and forget to look at your gauges,” one had told me. When my instructor took me to 130 feet during my training, I felt normal for the most part, though a bit chilled and nervous. My instructor had given me some simple math problems at the surface and timed me while I completed them, and now, using his slate, he asked me to do the problems again. I was just as quick and accurate underwater. But I was relieved when we began our ascent. By 75 or 80 feet, I was relaxed and enjoying the reef again. Later, I learned that for some divers, being narced causes anxiety rather than euphoria.

Researchers don’t know for sure what causes nitrogen narcosis in divers, but here’s what we do know:

Your thinking process slows down. In an emergency, you’re more likely to make mistakes.

You can’t multitask as easily. You tend to fixate on a single thing — like the “pretty fishies.” That means you’re not thinking about your gas supply, time, depth, etc.

You lose short-term memory. That means you could forget your dive plan.

TO AVOID THE EFFECTS OF NITROGEN NARCOSIS:

1. TAKE A COURSE IN DEEP DIVING
You’ll learn the warning signs of narcosis and the skills to deal with it.

2. MAKE SURE YOU'RE RESTED
Fatigue might be a contributing factor.

3. AVOID ALCOHOL AND DRUGS A hangover, and even the effects of over-the-counter drugs, can make narcosis worse.

4. PLAN YOUR DIVE, DIVE YOUR PLAN
Decide depth, route, frequency of buddy checks, etc., and stick to it.

5. WATCH YOUR BUDDY
Does he seem uncoordinated? Silly? Acting odd? If so, signal to him to ascend. Often, an ascent of only 10 or 20 feet will clear your head.

 

Check Out Our Dive Centre

Tags: diving

Dive Gear Maintenance Made Easy

Posted by Ericka Villa on Wed, Jan 20, 2016 @ 01:36 PM

Tags: Scuba Diving Gear, scuba diving, diving, scuba gear, scuba

10 Reasons To Be A Scuba Diver

Posted by Ericka Villa on Mon, Jan 18, 2016 @ 11:19 AM

scuba diver ascending

 Posted by Julie Clarke-Bush 

Why learn to scuba dive? Good question.

There are many reasons to learn to scuba dive. It may be something to mark off your bucket list, a reason to travel or even a way to escape the effects of gravity.

If you’ve been thinking about it and haven’t taken the plunge, here is a top 10 list of reasons to learn to dive.

Explore parts of the world that many don’t get to see

The ocean covers 71 percent of the earth’s surface. If your goal is to “see the world” then you’ll need to learn to scuba dive.

You have a place to escape everyday technology and Zen out

There are no phone calls to answer or emails to respond to underwater. Your attention is focused on breathing and what you see through your mask (which most of the time is pretty awesome!).

Experience weightlessness

Is gravity always bringing you down? Learn to dive and feel the sweet spot of neither sinking nor floating.

Improve your equalisation skills for flights and mountain drives

Once you master equalising your ears on a dive, you can do it anywhere.

Relive the vast amount of history that lies beneath the sea

You can explore wrecks that sit at the bottom of the ocean, including World War ships and planes.

wreck diving

Tank carrying muscles help you be better at bowling

#Strike

Master of non-verbal communications

Scuba divers learn to communicate underwater without speaking. The “this way to the exit” hand signal is very handy when you want to signal your date that it’s time to leave the party!

Impress others with your newly acquired knowledge

You’ll learn about PSI and compressed air in your scuba cylinder. Since you know an empty tank weighs less than full tank, you’ll know that a deflated football weighs less than one fully inflated.

You can one-up your friends on social media

This is especially useful if you have a lot of friends who run marathons…

You know that “Keep Calm and Carry On” is a real thing

After you get certified you’ll understand the importance of making your air supply last. The trick is to breathe slowly and move deliberately. Good advice for the surface too.

 

 

You really should learn to dive, don’t you think? 

Check Out Our Dive Centre

Are there other reasons we missed? Let us know in the comments.

 

 Posted by Julie Clarke-Bush 

Tags: scuba diving, diving

Myths about Scuba Diving

Posted by Ericka Villa on Tue, Jan 12, 2016 @ 10:34 AM

BY MICHAEL ANGE 

 
Ok Signal Scuba Diver

 

Myth: Diving — that was my grandfather's sport

Truth: If you think scuba isn't extreme enough for you, you're not seeing past the first step. Sure, a lot of people never go beyond puttering around in nice, calm water, looking at nice, calm fish. But if you get the right training and equipment, you can get radical with this sport. Try swimming through the surf zone off Southern California and it's you who'll need the Geritol, not Grandpa. Need more? Ever hand-feed a shark? Explore the far reaches of a flooded cave? Chase a 400-pound fish through the legs of an offshore oil rig? Go inside the rusting hallways of a sunken ocean liner? Swim beneath the polar ice caps? These are just some of the experiences that divers — and only divers — get to have. But you've got to build up to it, junior. So check your ego at the door, show Gramps a little respect and take the first step — earning Open-Water certification — before you start talking smack. Or better yet, pull Grandpa aside and ask him to tell you about that dive he never told Grandma about.

Myth: Diving is only for people who live in the tropics

Truth: There are few things that rival the experience of being suspended weightlessly in warm, clear tropical water while floating effortlessly along a colorful coral reef. Unless, of course, it is the experience of drifting through a California kelp bed with a pod of sea lions. Or exploring the amazingly preserved ruins of a wooden shipwreck in Lake Michigan. Or finding a million-year-old shark tooth completely intact in South Carolina's Cooper River, or ... the list goes on and on.

No matter where you are, chances are there's a popular dive site somewhere nearby. Don't believe me? Just ask anyone with the red and white diver down flag on his car. Lakes, quarries, rivers, flooded mineshafts — almost anywhere there's water, you'll find divers. Heck, outside of Abilene, Texas, you can even dive in a flooded underground missile silo. Each of these sites provides its own unique dive experience and a chance to get started in the sport. Not every dive site is for every diver, but scuba diving is not just a sport, it's also a lifestyle and a very social activity. So even if your local swimming hole isn't a world-famous dive site, an outdoor grill, a cooler, a couple of tanks of air and a dozen of your new best friends can still make for a whole lot of fun--palm trees, optional.

Myth: There are sharks in the ocean and they eat divers. Don't try to deny it — I saw Jaws and Open Water

Truth: Don't tell Hollywood, but the factual record on shark vs. diver is pretty dull: Sharks just don't make a habit of munching on divers. In fact, except in certain conditions and environments, they don't even stick around when divers get in the water. Let's look at it from the shark's point of view. You're out cruising the depths, when out of nowhere this noisy, bubble-blowing pack of creatures that looks and moves like nothing else in the ocean drops into the water and starts flashing lights (i.e., camera strobes) at you. It's got to be the shark equivalent of Close Encounters. The first thing most sharks do? Turn tail and run.

It used to be that divers could go their whole lives without ever seeing the beauty and majesty of a shark up close. Today, carefully managed encounter dives — from cage diving with great whites off Australia to hand-feeding reef sharks in the Bahamas — abound, and there is no better way to gain a true understanding of these amazing creatures than to see them up close.

Still not convinced? Then let me give you something serious to worry about instead: your dog. Yep. Behind those puppy dog eyes and that happy-to-see-you personality lurks the heart of a cold-blooded predator that's statistically far more dangerous than any shark. According to emergency room records, "man's best friend" killed 27 and seriously injured or maimed 4.7 million people in 2005, and that was just in the U.S. According to the International Shark Attack File, only four people worldwide died from shark attacks in the same 12-month period, out of 58 total recorded incidents. Based on those odds, you're safer in the ocean than taking Rover for a walk.

Myth: I have to buy a ton of gear just to learn

Truth: Scuba is a gear-intensive sport, but you only need three basic items to start lessons — a mask, a snorkel and a pair of fins. These are personal gear items and they need to fit well for you to have a good time, so it's worth buying them even if the shop provides loaners.

All the other gear is available to rent, usually at a discount rate to students, and sometimes the use of the more complex equipment is included in the dive package price.

Once you are a full-fledged diver, you will ultimately want to purchase your own gear. It will be tempting to max out the plastic and buy everything in one fell swoop, and if you've got the room on your cards, go for it. But most beginning divers continue to make use of rental gear and acquire their own items one piece at a time.

Myth: You have to be a speedo-sporting competitive swimmer to be a diver

Truth: Sure, ultra-fit, competitive swimmers make great divers because they're comfortable in the water and they're in great shape, but if the logic of this myth were true, I suppose only Tour de France racers would ride bikes.

Diving is an active sport and the better shape you're in, the easier it will be, but any healthy individual with at least an average fitness level can do it. This myth is most likely fueled by the fact that there is a basic swim test at the start of scuba lessons. You'll need the endurance to swim about 200 yards nonstop, but there's no time limit and it's not a race. The instructor also needs to know that you have basic water skills and are comfortable submerging your face in water. That's it. And when you consider that there are divers from age eight to age 80 who have passed this grueling test of physical ability, it's pretty clear that anyone with an activity level above that of a chronic couch potato can do it. So, get off the couch and go diving already. And please — regardless of your fitness level--leave the Speedo at home. OK?

Myth: Diving is a macho sport that is not female-friendly

Truth: This might have been true, back in the 1950s Sea Hunt era when men of steel like Mike Nelson (played by the late, great Lloyd Bridges) were out there spearing fish with their bare hands and rescuing damsels in distress. Only it wasn't really true then, either. The lovely Zale Parry, the actress who played the damsel, was one of the most accomplished divers on the set. And when Sports Illustrated decided to feature the young sport of scuba diving in its May 23, 1955, issue, it was Parry who made the cover.

It is true, however, that men have always participated in the sport more than women, but the gap has been closing steadily since the 1980s. Today, the male/female ratio is roughly 60/40 and everyone from equipment manufacturers to tour operators offer products specifically for female divers. And there's no glass ceiling to this sport — there are female instructors, divemasters, boat captains and resort owners.

Myth: Diving will make my ears hurt

Truth: This one's true — but only if you don't equalize the pressure in your ears as you descend. That's one of the first things they teach you to do in scuba lessons. It's called the Valsalva manuever and it's falling-down simple: Pinch your nose and blow gently against your nostrils until you feel relief. Try it. See? It's easy. Don't you wish you'd known this trick back in fifth grade when you were diving for quarters at the bottom of the YMCA pool?

Myth: Certification is way too expensive

Truth: You don't get out much, do you? Check the price for a decent dinner, movie tickets for two, throw in some popcorn, after-movie coffees and you'll drop $100 — easily — assuming, of course, there was no drive-through involved in ordering dinner. So, how does that compare to scuba? Depending on where you are in the country, the average certification class runs between $250 and $500, or just a few of those dinner-and-a-movie dates. In return, you get an all-access pass to a world of aquatic adventure, not to mention a great new lifestyle you can brag about at the office. Go on: Compare the cost of scuba lessons to almost anything and you'll see it's a bargain, especially compared to greens fees, lift tickets and the cost of that home gym collecting dust in your guest room.

Myth: I can't dive. I have (insert name of medical condition here)

Truth: Why not get a second opinion? Doctors are a very cautious bunch and often don't understand the sport of diving, so if you ask about scuba with regard to a specific medical condition, their likely answer will be the safe one: No.

But before you let a lifetime of adventure slip away, you and your doctor should consult the diving medicine experts at the Divers Alert Network (DAN). This nonprofit safety organization is affiliated with the Duke University Medical Center, and they can help you better understand the physical demands of diving and how it relates to your health. Call their nonemergency questions line at (919) 684-2948 and you may be surprised to find the answer is: Yes, you can dive safely.

In just the past 10 years, for example, asthma and diabetes have gone from being absolute disqualifiers to conditional ones. In both cases, if the condition is carefully monitored and controlled, and the patient can tolerate physical exercise, the pool is usually open.

Myth: Snorkeling is just as good as scuba diving

Truth: Don't get me wrong. I like to snorkel — floating around on the surface peering down on the reef from above is a great way to spend time between dives. But just as good? No way! Not if you like action.

Snorkeling is sort of like watching a football game from the window of the Goodyear blimp high above. Diving is like suiting up, running down the tunnel and getting in the game. Strap a tank on your back and you are a player — swimming with the sharks as equals, getting up close and personal with giant Goliath grouper, or, for a good laugh, looking up and seeing the soft, bulging underbellies of all those snorkelers drifting like flotsam on the surface and blocking out the sunlight.

Check Out Our Dive Centre

Tags: scuba diving, diving, myths

5 Diving Tips For Saving Air

Posted by Ericka Villa on Mon, Jan 04, 2016 @ 10:52 AM

Do you breathe your tank down faster than your buddy? Here are 5 diving tips to help conserve your oxygen and extend your bottom time.

1. Fix the small leaks
Even a tiny stream of bubbles from an O-ring or an inflator swivel adds up over 40 minutes, and may be a sign of more serious trouble ahead anyway. A mask that doesn't seal is another kind of leak in that you have to constantly blow air into it to clear out the water. It's also a source of stress, which needlessly elevates your breathing rate and thereby reduces your breathing efficiency. Does your octo free-flow easily? That can dump a lot of air quickly. Detune it or mount it carefully so the mouthpiece points downward.

2. Dive More
Inexperienced divers are famous for burning through their air supply at a furious rate, so one of the best diving tips for saving air is to simply dive more often. You may not be a new diver, but unless you dive almost every week it's still an unnatural activity. By diving more, your body will get used to the idea, and you'll breathe less.

 

 

3. Swim Slowly
The energy cost of speed is even more than you might think: Swim half as fast as you do now, and you'll use less air.

4. Stay Shallow
Because your regulator has to deliver air at the same pressure as the water, a lungful at 33 feet (two atmospheres) takes twice as much out of your tank as does the same breath at the surface. At 99 feet (four atmospheres) it takes twice as much as at 33 feet. There's absolutely nothing you can do about that except to avoid being deeper than you have to be. If you're making a transit over an uninteresting sand flat to get to the edge of the drop-off, do it at 15 feet instead of at 40 feet, and you'll save air.

5. Minimize the Lead
If you're overweighted, you have to put more air into your BC to float it and be neutral. The inflated BC is larger and requires more energy and oxygen to push it through the water. An extra eight pounds of lead means your BC is one gallon bigger when inflated enough to make you neutral.

 

For more diving tips and diving courses, 

Check Out Our Dive Centre

 

Source: http://www.scubadiving.com/training/basic-skills/5-diving-tips-saving-air

Tags: diving

Five Tips For Handling Underwater Scuba Diving Emergencies

Posted by Ericka Villa on Tue, Dec 15, 2015 @ 11:11 AM
Happy Diver Under the Water

 

You will survive: Five tips to handle anything the ocean dishes out.

While rare, underwater emergencies can — and do — happen. Here’s how quick-witted divers prepare for crises.

1. Learn Self-Reliance You can’t help others if you can’t help your- self first. Knowing that you can take care of yourself is the first step in pre- paring for underwater emergencies; a rescue-diver course is a great way to build skills and confidence.

2. Maintain Your Gear Equipment problems are the easiest underwater emergencies to avoid. Have your reg and BC serviced regularly, check your mask and fin straps for cracks, and do a predive check before you enter the water.

3. Follow A Plan “Plan your dive and dive your plan” is about more than just sticking to your dive profile. It means understanding the challenges you might face on each dive, and en- suring everyone who is going into the water has the proper skills and equipment to deal with those challenges.

4. Be Proactive The best way to deal with an emergency is to stop it before it starts. Keep an eye on your dive buddy or group, watching for telltale signs of trouble, such as a diver with wide, unseeing eyes who might be on the verge of a panic attack.

5. Know Your Escape Route In a crisis, your top priority is getting yourself and the victim out of the water quickly and safely. On shore dives, this means knowing how to reach your exit point from the surface. On boat dives, it means learning the crew members’ emergency protocols.

 

Get a Quote for Vacation

BY TRAVIS MARSHALL POSTED NOVEMBER 4, 2015

Tags: diving tips, diving, dive resort cebu, divers injuries

Tips for Night Diving

Posted by Ericka Villa on Mon, Dec 07, 2015 @ 05:09 PM

When the sun goes down, the underwater world transforms into whole new territory. Consider these tips to truly shine at night diving.

 

Night Dive 

Scope Out the Site in Daylight

Be familiar with the site you plan on embarking on a night dive in. Do reconnaissance during the day so that you know and are comfortable with the area.

 

Have the Right Gear

Divers will need both a primary dive light and a backup light for optimal security. The primary light is the larger and brighter device while the backup flashlight is small and easy to carry.

 

Let There Be Light

On a night dive, lights from bioluminescence, the moon and other divers may be sufficient to guide divers. Once your eyes are accustomed to night diving, you will be amazed by what you will see.

 

Stay Close

Night dives are typically shallow dives at an average depth of 30-40 feet.

 

Take Things Slow

With shallow dives, night divers have lots of time to go slow, explore and take it all in. Colours are more vibrant when diving at night than when diving in the day.

 

Know the Signals

Establish and review hand signals with your group before your dive. Determine how you will communicate important commands and answers while underwater.

 

Mark Your Entry Point

Track your entry trail for an easy exit. When diving from a boat, mark your vessel with a flashing strobe light. If diving from the shore, place lights on the beach.

Tags: diving tips, diving, night dive

Get To Know Your Scuba Cylinder

Posted by Ericka Villa on Mon, Dec 07, 2015 @ 04:59 PM

By  Beth Alexander

As divers, we know that SCUBA stands for Self Contained Underwater Breathing Apparatus, but how much do you really remember about cylinders? Here’s a brief review to help you tell your aluminum from your steel and your DIN from your yoke.

What are scuba cylinders made of?

Cylinders are made either of steel or aluminum, with each having its own advantages and disadvantages.

Steel is harder than aluminum and therefore doesn’t damage as easily. It’s also heavier, meaning that divers don’t to carry as much weight. Once a diver has breathed the air out of the tank, he stays the same weight in the water, which helps with buoyancy.

Steel is prone to rusting, however, which is problematic for any piece of dive equipment, but especially for a cylinder, as you want your tank to be clean, dry and rust free to stop any potential air contamination or valve blockages.

Aluminum cylinders are lighter than steel and are also a lot less expensive. They are the most commonly used tanks at dive resorts. Because they’re lighter, they’re also widely used in technical diving, wherein divers must carry many tanks at once. Aluminum tanks are also useful for side-mount diving due to their buoyancy attributes.

However, since these tanks are a lot lighter than steel, divers must carry more weight. Also unlike steel tanks, aluminum cylinders change buoyancy from negative to positive as a diver breathes down the air, which means that the tank begins to float. Some divers may find this difficult to control.

What are cylinder valves?

Each scuba cylinder has an on/off valve, and each valve contains a “burst disk,” which is a safety feature designed to burst and release cylinder pressure if it’s overfilled or if the pressure builds due to heat expansion. Tanks also have different types of valves.

The most common is the K-valve, which has a single outlet to allow the connection of one regulator, and has no reserve function. It simply opens to allow gas to flow and closes to shut it off.

Y- and H-valves have two outlets, each with its own valve, which allows attachment of two regulators. This means that you have a failsafe — if one regulator fails or free flows, you can simply close the valve and breathe from the regulator that’s connected to the other valve.

Before the K-valve became common there was the J-valve, which had a lever that allowed the diver to pull and release the remaining air reserve if a low-on-air situation was approaching. These have since been replaced by the safer and more reliable K-valves.

What’s the difference between DIN and yoke?

Quite simply this is how you connect your regulator to your cylinder. Yoke connections are made when the regulator surrounds the valve and a seal is created against the O-ring when the cylinder is turned on and the pressure is released. A DIN connection is made when the regulator is screwed directly into the cylinder valve. It’s more reliable and secure, however it’s uncommon in many places, so an adaptor maybe required when traveling.

What do the markings stamped along the top of the tank mean?

You’ll notice that there are a lot of letters and numbers stamped onto the neck of a scuba cylinder — this isn’t a secret code meant only for dive professionals. The information contained therein is useful for you as well, from basic information about the material it’s made from to safety regulations regarding cylinder test dates.

Below is an example of the stamp on a cylinder and what each section means.

stamp

 

So the next time you go diving, pay some attention to your cylinder, whether it be test dates, the type of valve, or the material from which it’s made in order to adjust your weights. All the information is there, but if you’re ever unsure, never hesitate to ask a dive professional.

 

Check Out Our Dive Centre

 

Tags: diving

Dive Better, Dive Safer: 101 Tips That Will Make You A Pro

Posted by Ericka Villa on Tue, Dec 01, 2015 @ 02:34 PM

DIVE BETTER, DIVE SAFER

Hit the Pause Button 4 Times

Get in the habit of inserting pauses in your dive plan. It's a chance to take stock, collect yourself and relax a moment.

  • After you're geared up, pause a moment: Forget anything? Does everything feel right?

  • After you enter the water but before you submerge: Is your weight belt still in place? Is your buddy OK? Is there current?

  • After you reach max depth but before you move off: How do you feel? Check your equipment, check your gauges, check your buoyancy, check your buddy. Look around so you can recognize the scene when you return and are trying to find the anchor line.

  • After you finish your safety stop but before you surface: Hear any propellers? Check your buoyancy.

6 Tips for Better Buoyancy Control

  • Minimize your weighting. Extra air in your BC, to support extra lead on your belt, will change volume and buoyancy with depth, causing you to yo-yo and preventing you from maintaining neutral buoyancy.

  • Check it at the safety stop. It's at the end of your dive, not the beginning, that you should be weighted for neutral buoyancy at 15 feet. That means you'll be about five pounds heavy at the beginning of the dive. (That's the weight of the air you use.)

  • Suspend a weight bag. Hang a mesh bag with some one-pound and two-pound weights from the boat at about 15 feet. Start the dive with two pounds or so of your weight in a BC pocket. At the safety stop, next to the weight bag, you can transfer weights between pocket and bag to find your perfect weighting.

  • Relax. To find neutral buoyancy, go limp. Any sculling with hands or feet will create upward thrust.

  • Add and subtract air in small squirts. You must wait a minute for adjustments to take effect before adding or subtracting more. The effect is not instantaneous.

  • Use your lungs, not your BC. Make slight temporary changes to your buoyancy by holding more or less air in your lungs. That way you don't disturb the correct inflation of your BC. Hold air with your chest, not by closing your glottis, so pressure can escape.

17 Ways to Reduce Air Consumption

  • Streamline your equipment. Stash accessories in pockets or leave them behind. Reduce the lengths of your hoses where you can and route them close to your body. Clip in your console and your octopus. Choose a BC sized properly for your body and for the buoyancy you need; too much causes excess drag.

  • Drop weight. The less weight you carry, the less air you have to put into your BC to maintain buoyancy, so the less bulk you have to drag through the water. You use more air dragging more bulk around. Most divers can drop two pounds or so.

  • Get neutral. And get trimmed properly, so that when you're neutral, you're horizontal. That minimizes the size of the "hole" you have to make in the water when you swim.

  • Move slowly. Water resistance increases exponentially with speed. Swimming twice as fast requires four times as much energy. All your movements should be in slow motion.

  • Kick within your slipstream. Keep your fins within that "hole" in the water made by your body. Wider kicks increase drag.

  • Use efficient fins. Some deliver more thrust for a given effort than others, especially split fins. See ScubaLab tests in our Gear section for details.

  • Don't skim the bottom. Both the bottom and the surface cause turbulence that robs energy if you swim within a few feet of them.

  • Make long surface swims on your back. And breathe surface air: It's free.

  • Pause after inhaling. Under water, your breathing pattern should be inhale, pause, exhale, inhale, pause, exhale. The pause (held with your chest muscles, not by closing your throat) allows more gas transfer to take place in your lungs and less oxygen to be wasted.

  • Breathe slowly. Friction between the incoming air and your mouth, throat, lungs, etc. increases exponentially with speed. More friction means more energy expended for less air actually arriving in your lungs. Move the air slowly.

  • Breathe deeply. The more complete each breath is, the fewer of them you have to take. Breathe "from the diaphragm," trying to completely fill and completely empty your lungs.

  • Use a high-performance regulator. Better regulators minimize the work of breathing. They minimize the amount of air you burn just getting air.

  • Maintain your regulator. They lose performance and increase work of breathing with use and age, and need regular maintenance.

  • Readjust your regulator. On many regulators, the purpose of the adjustment knob is not merely to prevent free-flowing on the surface. It's also to minimize work of breathing at depth. Periodically during your dive, open the valve until the regulator just begins to bubble, then back up on the adjustment a bit.

  • Stop all leaks. Lots of little bubbles add up. Usual suspects: tank O-ring, BC inflators, console swivels.

  • Stay above. At five feet less depth than your buddy, you'll see almost everything he does, but you'll use substantially less air. (Though the difference is greatest at shallower depths.)

  • Manage currents wisely. Learn how to detect, avoid and cope efficiently with adverse currents.

4 Ways to Be a Better Buddy

  • Communicate. Dive planning means talking. Don't assume you both know what to do. Be explicit about depth and time limits, buddy separation procedure, etc.

  • Two-way gear check. The gear check isn't over when you've checked your buddy's gear. He or she must check yours too. That forces your buddy to put hands on the gear, to take responsibility for it being correct. Likewise, make sure gauge checks during the dive go both ways.

  • Take turns. During the dive, don't always be the one who leads, because that trains your buddy to be a follower. Make a point of trading off, so your buddy takes as much responsibility as you for setting the pace and direction.

  • Be humble. Admit you can be wrong. Don't dismiss your buddy's warning/correction/suggestion out of hand.

3 Tips for an Out-of-Air Ascent

  • Relax. Easier said than done, but many "out-of-air" emergencies are really cases of anxiety causing the diver to overbreathe the regulator. Slow your breathing, and you may find you have plenty of air after all.

  • Keep your reg in your mouth. You may be totally out of air at depth, but keep trying to breathe. As you ascend and ambient pressure falls, more air will probably become available from your tank.

  • Exhale slowly. The air in your lungs expands as you ascend, and it's not uncommon to exhale all the way up and reach the surface feeling you have more air in your lungs than when you began the ascent.

5 Tips for Mapping a Dive Site

  • Sketch the dive site on your slate. Actually drawing it is a memory aid. It helps even if you never look at it again.

  • Orient toward north. Draw the map so north is at the top. Under water, lining up your slate with your compass needle puts things in proper orientation. Mark the direction of the sun and the current, too.

  • Use navigational charts. Or other site sketches to get the overall shape.

  • Listen to the dive briefing. Ask questions about depths, trend of bottom and underwater topography.

  • Use your eyes. Above-ground profiles often extend under water; a cliff above is often a wall below.

9 Ways to Minimize Your DCS Risk

  • Ascend slowly. A slow ascent rate is a "rolling" decompression stop that allows nitrogen to offgas before it bubbles.

  • Make a safety stop. It's not called a decompression stop, but that's what it is. It allows more offgassing before you ascend through the final 15 feet, where pressure change per foot is greatest.

  • Don't exercise after diving. It seems to increase formation of bubbles. "Like shaking a can of soda," some people say.

  • End the dive shallow. When you are ascending, you're offgassing from the faster tissues, which are usually most critical for neurological DCS. Time spent shallow at the end of the dive helps unload the nitrogen taken on during the early, deeper parts.

  • Avoid sawtooth and bounce profiles. It's believed that repeated ascents and descents increase the chance of microbubbles passing to the arterial side of your circulation.

  • Wait 24 hours before flying. Flying soon after diving has the effect of making the dive deeper, and bubble formation is greater.

  • Stay warm. If you're cold, your circulation is restricted and nitrogen is passed off more slowly.

  • Stay hydrated. If you're dehydrated, your blood is thicker and moves more slowly, so offgassing is slower.

  • Don't use all the green. Computer algorithms are predictions, not guarantees. Back off a "click" or two for more safety.

5 Compass Tips

  • Practice on land. Try walking around a parking lot or a football field while looking mostly at the compass. When you can return to your starting point, you'll be better able to do the same under water.

  • Make sure the card rotates freely. If it hangs up, the reading will be wrong. Check by rotating the compass in your hand: The card should not move.

  • Fine-tune your buoyancy. Get in trim before taking a compass reading. If you are fighting to maintain your attitude, you will be more likely to get a false reading.

  • Use the bezel. Rotate it to mark your course. Checking your course requires only matching the north arrow to the bezel mark (or something equally simple, depending on the design of the compass).

  • Mount the compass on a slate. The slate helps you level the compass and is handy for marking bearings. Console mounts are often difficult to level because of the stiff hose.

15 Seasickness Tips

HOW TO AVOID IT:

  • Pop a pill. All the pills are about the same in effectiveness and side effects. But if one of them—Dramamine, Bonine, Marazine, etc.—seems to work better for you than the others, stick with it. The placebo effect is very strong with seasickness.

  • Start taking pills early. Pills are better prevention than treatment. After you feel queasy, it may be too late for pills to help, so start 12 to 24 hours before going to sea. This builds up a level of the drug in your body.

  • Try the patch ... Scopolamine patches do work better than pills and have fewer side effects for most people. They are available by doctor's prescription.

  • ... Or the bands. Some people like "Sea Bands." They are bracelets with dots that purportedly touch acupressure points on your wrist. They have never been proven effective, but some people swear by them.

  • Bigger is better. Bigger, and especially wider, boats have a slower roll than smaller ones.

  • Stay on deck. It helps to be able to see the horizon, possibly because your eyes then agree with what your middle ears are saying—that your body is rocking and pitching. One theory is that nausea is caused by mixed messages when, below decks, your eyes report that all is stationary.

  • Don't try to read. Focusing your eyes on an apparently stationary target makes them even more convinced that your middle ears are wrong.

  • Close your eyes if you must go below. You may have to go below and lie down, in which case you should close your eyes so they aren't giving a no-motion message to your brain.

  • Be clean and sober. Even a mild hangover can easily degenerate into seasickness, besides increasing various diving risks. Likewise, fatigue predisposes you to seasickness.

  • Eat something. Opinions vary on this one, but most people feel better with a little bland food on their stomachs. Bread, bagels, pancakes, etc. are better than eggs and bacon. Coffee and orange juice are acidic and may irritate your stomach. Eat a little, not a lot.

  • Relax. Anxiety contributes to seasickness. Those who are frightened by the ocean and the movement of the boat, or anxious about the diving later in the day, are more likely to become seasick.

  • Watch for symptoms. Early signs include chills, headache and frequent burping. Now is the time to go on deck, or move to the lee rail if you're already there.

I'M SEASICK: NOW WHAT?

  • If you feel the urge, let it rip. You'll feel better almost immediately. Prolonging the inevitable only prolongs the pain.

  • Don't use a toilet. Or, God help us, a trash can. Go to the rail on the lee (downwind) side or use a bucket if one is designated. If you feel the urge coming, ask a crew member where to go. He or she will know the best place. Don't be embarrassed; you're not the first.

  • Get over it. After a few hours, most people feel better. For some it takes a day or two. Almost everyone gets over seasickness within three days.

6 Ways to Stay Warm

  • Wear a hood. It should be the first piece of thermal protection you consider, not the last. While near-surface blood vessels elsewhere in your body close down to minimize heat loss, those in your head continue at full flow.

  • Stop the leaks. The best wetsuit or dry suit is worthless if it lets in too much cold water. Repair broken zippers and split seams. The collar seal is especially important because as you swim forward it tends to scoop in water. Wear a hood if for no other reason than to seal the neck opening.

  • Cover up head to toe. Heat loss is huge where cold water flows over bare skin, so a thin full-length suit is warmer than a thicker shorty.

  • Stay shallow. Shallower depths mean the insulating neoprene of your wetsuit won't compress as much. And breathing air under less pressure chills you less.

  • Surface if you shiver. Uncontrollable shivering is a warning sign of hypothermia.

  • Break the wind. Between dives, a wet exposure suit becomes a swamp cooler. Many divers actually lose more heat between dives than when in the water. Wear a parka or a windbreaker, or take off the suit and dry off.

10 Ways to Avoid Nitrogen Narcosis

  • Take a course in deep diving from a qualified instructor. You'll learn warning signs of narcosis and skills in coping with it, and you'll gain confidence. Nitrogen narcosis can build on anxiety.

  • Be rested. Fatigue accentuates nitrogen narcosis.

  • Be clean and sober. A hangover, even the effects of over-the-counter drugs, can make narcosis worse.

  • Exhale thoroughly. You'll expel more carbon dioxide, which seems to accelerate the onset of narcosis.

  • Plan your dive, dive your plan. Decide depth, route, frequency of buddy checks, etc. and stick to it. Leave as few decisions as possible to be made "under the influence."

  • Watch yourself. Sure, it's supposed to be fun, but this much fun?

  • Watch your buddy. Does he seem uncoordinated? Silly? Acting odd?

  • Don't become fatigued. Don't try to do too much.

  • Watch your instruments. Believe them.

  • When in doubt, ascend. Often, an ascent of only 10 or 20 feet will clear your head.

8 Dive Boat Dos and Don'ts

 
Space is usually at a premium on dive boats, so secure your gear as neatly and compactly as possible.

DO:

  • Be early to board, early to gear up. Rushing increases anxiety and stress.

  • Remember cash for tips.

  • Secure tanks and weights and all other gear as instructed by crew.

  • Dress completely at your gear station except for putting on fins. Walk fins-in-hand to the exit door.

DON'T:

  • Leave open drinks on the camera table.

  • Dip masks in the camera rinse tank.

  • Forget your C-card.

  • Invade dry areas in a wet exposure suit.

9 Ways to Never Get Lost

  • Descend feet-first. And try to remain facing in the same direction, so you can correlate what you see on the bottom with what you saw at the surface.

  • Stop before you go. When you reach bottom, stop for a moment. Use yourcompass to orient yourself to your map. Look around for landmarks that will help you identify the scene when you return.

  • Use bottom contours. If you know the anchor is at 60 feet, you can find it by following the bottom slope to 60 feet, then following that contour.

  • Plan your route. Like, "Up-current at the 80-foot contour for 1,200 psi, then return to the exit at the 60-foot contour." Following your nose in a random pattern is more confusing.

  • Look for landmarks. When crossing a flat bottom, look for memorable landmarks in sight of one another: a rock outcrop, a large sponge, a bit of litter. Make your transit of the bottom a series of legs, from A to B to C to D, and you can find your way back.

  • Look behind you. On an out-and-back route, look back from time to time. You'll be more likely to recognize the scene on your return. Landmarks often look different from the other side.

  • Note compass headings. If you need to make an underwater transit from the descent line or anchor to the reef or the top of the wall, note the compassheading and note the scene when you arrive. The reciprocal course will return you to the anchor.

  • Note the direction of the sun. You can usually see it from under water. If it's on your left when outbound, it should be on your right for the return.

  • Learn the names. When you can identify the different sponges, corals, etc. along your route, you are more likely to remember them.

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Divers photo by Shutterstock.com

Source: http://www.scubadiving.com/training/basic-skills/dive-better-dive-safer-101-tips-thatll-make-you-pro

Tags: scuba diving