By Mark Young
“For the want of a nail, the shoe was lost; for the want of a shoe the horse was lost; and for the want of a horse the rider was lost, being overtaken and slain by the enemy, all for the want of care about a horseshoe nail.”
–Benjamin Franklin, Poor Richard’s Almanack
The cover story for this edition took me back to an article that ran in the second issue of Dive Training — December 1991. It was a Learning Experience column written by a guy who got into trouble diving from a private boat.The reason that article readily comes to mind is because I never forgot it; I’ve always been amazed that it’s so possible for intelligent people to do dumb things. More about that in a minute, but here’s a recap of the event.
So the author’s friend calls and asks if he would like to go lobster diving. The friend owns a boat, they’re in South Florida and the Gulf Stream should make it an easy drift dive; the divers will tow a float, which the boat will follow to pick them up at the end of the dive.
On this day the boat will be driven (and the float will be followed) by the guy’s new girlfriend. She’s never done this before; in fact he’ll teach her to drive on the way to the dive site. It’s just the three on board so she will also be alone on deck as the sole observer. None of this is too smart so far.
Before leaving the dock they question whether to dive. The seas are running 2 to 4 feet, expected later to become 3 to 5. They decide they can beat that, and go. The wind is picking up when they reach the site so their next good idea is that it’s a good idea to get diving and get back soon. In other words, no time for predive briefings or much of a dive plan or, for that matter, to show her how to use the boat’s radio or find her way back to an inlet if necessary. It’s also getting pretty late in the day. They continue on and make the dive.
You can see what’s coming; why couldn’t they?
We tend to think that accidents come from out of the blue, but most don’t. They are usually at the end of a series of events. In fact far too often accidents or incidents are both foreseeable and avoidable. So why do even smart people do such predictably dumb things?
The best answers come from the archives of the National Transportation Safety Board, the operation that investigates airplane accidents. After thousands of well-documented cases, here is what they’ve determined.
The chain of events leading up to an accident is often called the error chain. At the start of the chain is almost always some human factor of personality, of judgment or fault. It’s the mental mechanism that, for example, keeps the pilot flying into iffy weather eager to make his destination when he probably shouldn’t have left to begin with, or should have fixed his gyro, or taken the time to top off his fuel tanks for margin, or had the opportunity to stop at numerous airports along the way. He instead ends up a statistic.
Those same human factors in play, the author of the story hesitantly yields to the boating experience of his friend, who committed to take his buddy diving and is hesitant to back out while the girlfriend, obvious to all to be incompetent for the task, wants to appear cool, capable and willing. There were also at least six event links along the error chain when any one of the three could have said no, and broken it. The horseman is slain, the pilot is lost and the divers adrift on a dark sea, worried as much about how the girl will get back home as about how they will. Lucky for all of them it ends up OK.
Diving from a private boat is fantastic fun. The how-to-do-it article in this edition is a very good primer. What is left to consider when it comes to both your ultimate safety and enjoyment, is awareness of that chain of events. Those not tuned in to their instincts are rarely aware that an accident is forming, so if divers and boaters pay attention and accept the responsibility for safety, most links will be broken before the chains that cause accidents can even begin. And at that time when your gut does kick in, you only have to break one link in the chain of events to never know what was coming.
In the end, it’s always better to be on shore wishing you were in the water than in the water wishing you were on the shore.
Monday, September 19, 2011
Saturday, July 16, 2011
FORGING FISH
By Mark Young
Perhaps the greatest art forger of the 20th century was Hungarian-born artist Elmyr de Hory (1906-1976). After studying classical painting at institutes in Germany and France, de Hory realized That his true artistic bent resided in the ability to copy the works of other artists, which he did prolifically. Picasso. Matisse. Renoir. Modigliani. De Hory claimed to have sold more than a thousand forgeries to art galleries and wealthy individuals around the world.
For example, it is beyond speculation that quite a bit of what you see on display in museums is not the real
deal. Museums have been suckered by forgers to the point that known forgeries remain on display, serious efforts to examine questionable objects are rare and, according to one museum whistleblower, “the system is supported by a mafia-like code of silence within museums and academe that conceals information and impedes exposure of the underlying process of plunder, forgery and smuggling.” Add that to the wonderment of your next museum visit.
Mostly we think of forgery in terms of money and art, but it’s rife in archaeology, literature, music, documents, history, perfumes, designer clothing, stamps, relics, religion, baseball trading cards, and even wine. So should it come as a surprise that forgeries are rampant among fish? One company in Florida, aided by export- exporta - mong export ers in Asia, imported thousands of pounds of catfish into the United States labeled and sold as grouper, just to avoid paying duties that the Department of Commerce had imposed on Vietnamese catfish.
That example is just one small act on the grand stage of seafood fraud that includes a multitude of illegal activities, undertaken by countless characters in countless places along the international supply chain. The fraud typically involves mislabeling (forging) seafood through the substitution of one species of fish — usually of inferior quality — for another, mostly for economic gain. The feature story that begins on Page 30 provides an interesting look into fish fraud; it’s a disturbing and informative article.
You can imagine that Elmyr de Hory’s career makes for good reading, and indeed he is the subject of a few books. The best was written by then-respected author Clifford Irving after extensive interviews with the subject. (“Fake! The Story of Elmyr de Hory, the Greatest Art Forger of Our Time” was published in 1969.)
So does the name Clifford Irving ring a bell? Just two years after publishing “Fake,” Irving pulled his own
So does the name Clifford Irving ring a bell? Just two years after publishing “Fake,” Irving pulled his own
“de Hory” using forged letters that he said were from Howard Hughes, to trick McGraw-Hill into buying a fake autobiography of the reclusive billionaire. However, while the subject of his previous book worked to
make his forgeries hard to detect, Irving had the brass to perpetrate his fraud and write the autobiography
with much fanfare, and dumber yet while Hughes was still alive. Irving went to prison for the scam, as did the owner of the Florida fish company, mere footnotes to the ever-growing market in fakes and forgeries where not everything is what it appears; perhaps not even that salmon fillet on the plate before you.
Enjoy this edition of Dive Training as you dine on
— whatever that is.
Wednesday, May 25, 2011
OCEAN'S DAUGHTER
Written by Mark Young
Benchley called his brother to tell what had happened to him and to ask a favor. The story is that Bench’s friends were going to the Caribbean and asked if he wanted to come along. He had to get certified, though, because they were going there to dive. Bench kind of always wanted to do that so he took lessons and a month later was with his buddies in the sun having a great time. He did his checkout dives at the resort and told George how he spent the rest of the week doing the most incredible stuff.
The question for George was more like a plea.“I’m going back. You have to get certified and come. I promise you’ll love it because you’re like me. You can’t say no. Leesy too.”
It’s George’s wife Lisa telling me this on the phone. She and George had talked about diving. They like outdoors stuff but the conversations about taking up diving usually stopped with her and a halfhearted, “Yes we should.” The conversation wasn’t going to end there this time. Bench had dragged Lisa and George off on other adventures and they were always fun, especially when he brought along his eternal fiancée (of seven years) who they all loved and rounded out the foursome. She had agreed to be certified too. There was no saying no.
Lisa went on. “I don’t know why I always managed to put it off, whether it was the money or maybe I was a little chicken about doing it — it was easier to shine it on. But we did it. We found a dive store that we didn’t know was here and our class had two other couples and two other guys. There were eight of us and by the second class we were comfortable with each other, and by the end we were at the bars and having a great time together. We became good friends. Diving was our common bond. But that’s not why I’m calling.”
She was calling to say they went off on their adventure with Bench, and that her life hasn’t been the same. She fell in love with the sea. She hasn’t been able get that phrase out of her head from the song by the Electric Light Orchestra. “They were singing about me, the ocean’s daughter. And how odd the title of the song, “Can’t Get It Out of My Head,” because that’s how I’ve been; profoundly changed. I asked her if George became the same way and she said no, that would be impossible. He loves it too but she’s gone nuts.
Most people come into diving pretty unaware. Blank slates, if you will. They know little about the equipment they will be using, are certainly unfamiliar with the skills and knowledge, and I contend that most new divers have never heard of the island of Bonaire. From the minute they first walk in, diving becomes a total learning experience.
The education goes past the bookwork and skills, to way beyond what they think this will be. New divers are soon to find out more than they know about the world’s history, geography and its people. They will learn some oceanography and lots about marine life and diving’s environments. But when they swim alongside of something alive and the size of a bus, or a wall that descends thousands of feet beyond unlimited visibility, they learn quite a lot about themselves. Prior personal experience and their very familiar world expand past something that they have imagined, to discover that it’s more. For many the observance and appreciation of nature on the scale where divers are privileged to be will become deeply personal. What is really coming in the way of learning, for the new diver, is often unexpected. Sometimes quite unexpected.
She called not just to tell me all that, but to ask if we could write something powerful that would entice other Lisas who are on the fence to give this a try. I believe she just did.
Midnight on the water
I saw the oceans daughter
Walkn'on a wave she came
Staring as she called my name
And I can't get it out of my head
No, I can't get it out of my head
Now my old world is gone for dead
'Cos I can't get it out of my head
-Electric Light Orchestra
Benchley called his brother to tell what had happened to him and to ask a favor. The story is that Bench’s friends were going to the Caribbean and asked if he wanted to come along. He had to get certified, though, because they were going there to dive. Bench kind of always wanted to do that so he took lessons and a month later was with his buddies in the sun having a great time. He did his checkout dives at the resort and told George how he spent the rest of the week doing the most incredible stuff.
The question for George was more like a plea.“I’m going back. You have to get certified and come. I promise you’ll love it because you’re like me. You can’t say no. Leesy too.”
It’s George’s wife Lisa telling me this on the phone. She and George had talked about diving. They like outdoors stuff but the conversations about taking up diving usually stopped with her and a halfhearted, “Yes we should.” The conversation wasn’t going to end there this time. Bench had dragged Lisa and George off on other adventures and they were always fun, especially when he brought along his eternal fiancée (of seven years) who they all loved and rounded out the foursome. She had agreed to be certified too. There was no saying no.
Lisa went on. “I don’t know why I always managed to put it off, whether it was the money or maybe I was a little chicken about doing it — it was easier to shine it on. But we did it. We found a dive store that we didn’t know was here and our class had two other couples and two other guys. There were eight of us and by the second class we were comfortable with each other, and by the end we were at the bars and having a great time together. We became good friends. Diving was our common bond. But that’s not why I’m calling.”
She was calling to say they went off on their adventure with Bench, and that her life hasn’t been the same. She fell in love with the sea. She hasn’t been able get that phrase out of her head from the song by the Electric Light Orchestra. “They were singing about me, the ocean’s daughter. And how odd the title of the song, “Can’t Get It Out of My Head,” because that’s how I’ve been; profoundly changed. I asked her if George became the same way and she said no, that would be impossible. He loves it too but she’s gone nuts.
Most people come into diving pretty unaware. Blank slates, if you will. They know little about the equipment they will be using, are certainly unfamiliar with the skills and knowledge, and I contend that most new divers have never heard of the island of Bonaire. From the minute they first walk in, diving becomes a total learning experience.
The education goes past the bookwork and skills, to way beyond what they think this will be. New divers are soon to find out more than they know about the world’s history, geography and its people. They will learn some oceanography and lots about marine life and diving’s environments. But when they swim alongside of something alive and the size of a bus, or a wall that descends thousands of feet beyond unlimited visibility, they learn quite a lot about themselves. Prior personal experience and their very familiar world expand past something that they have imagined, to discover that it’s more. For many the observance and appreciation of nature on the scale where divers are privileged to be will become deeply personal. What is really coming in the way of learning, for the new diver, is often unexpected. Sometimes quite unexpected.
She called not just to tell me all that, but to ask if we could write something powerful that would entice other Lisas who are on the fence to give this a try. I believe she just did.
Sunday, March 27, 2011
AS HISTORY SERVES
Written by Mark Young
On the morning of February 17, 1944, in a surprise attack by the United States, aircraft bombed Japanese warships and merchant vessels in Truk Lagoon, a strategic plot of wartime geography in the Central Pacific. The attack continued the next day and when it was over 52 ships and their crews were on the bottom. The destruction would have been far greater had the Japanese not seen U.S. reconnaissance planes overhead days earlier, anticipated the attack, and moved much of the fleet.
In 1945 the American government relocated the residents of the Bikini Atoll to another place in the Marshall Islands, to create an isolated spot and test the damage that could be inflicted by nuclear weapons. Among the tests, they wanted to see the effects on war vessels, and anchored a mock fleet in the blast area. Among the vessels sent to the bottom were the 880-foot (267-m) aircraft carrier USS Saratoga and, in a blast of irony, the Japanese battleship Nagota, from which Admiral Yamamoto directed the attack on Pearl Harbor.
November 23, 1984. A powerful storm ripped the Mercedes I from its temporary anchor in the Atlantic and landed the 194-foot (59-m) freighter up against a sea wall, literally next door to the Kennedy family’s Palm Beach, Florida, compound. The ship’s owners slithered off, and it took months for the state of Florida to have it pulled off the beach. Because of the unusual stranding, the moneyed neighborhood and the drama around the removal, the ship became a media celebrity. Just a few months later it began service as an artificial reef off the coast of Fort Lauderdale.
Shipwrecks, like people, have stories to tell. They rest where they are because of war, weather, malfunction, accident or by plan. A major allure of shipwrecks, certainly for divers who visit, are their histories. Certainly they all have interesting how-I-wound-up-on-the-bottom stories, but they have others. Many of the military ships that we are privileged to dive served in war. Others patrolled during peacetime to protect their country and the peace of others. Some ended up tracking space launches, or became spies, or were used as movie sets.
There are also very deep personal histories ascribed to each ship. Within each sailor who served, a military ship occupies a place usually reserved for a childhood home. For many it forged the rest of their life. For far too many, the ships became their grave.
And shipwrecks are surrounded by history. The push for America to stay ahead as a war power sent the Bikini fleet down. A total of 242 naval ships, 156 aircraft, 25,000 radiation-recording devices and some 5,400 goats, rats and pigs were subjected to the initial atmospheric nuclear blasts, which eventually numbered 23 over a 12-year period. Topping the chart was the monster of its time, a hydrogen bomb that vaporized three of the islands and spread radioactive debris over 50,000 square miles (130,000 sq km). In many ways the area is still reeling. The Bikini ships and the Ghost Fleet of Truk Lagoon essentially represent a placemark along man’s advancement from being savage to someday becoming civilized.
And finally, each wreck has an aftermath. Beyond any damage of war, or wear, or the sinking itself, ships are profoundly changed by the sea. They become cloaked in living biomass. Paradoxically colorful life camouflages the muzzles of guns as old ships become new environments. That part of a shipwreck’s history — the story to come — is the subject of the article in this edition as Alex Brylske talks about the ecological issues surrounding ships in their role as artificial reefs.
Quite a few ships have recently gone to reef by plan. In July 2000, the HMCS Yukon, a destroyer that served in the Royal Canadian Navy, was sunk by the San Diego Oceans Foundation after nearly 2,000 volunteers spent more than a year gutting and cleaning it for its role as a California artificial reef and dive site. Consider that, and you basically have the story of the USS Spiegel Grove, USS Oriskany and General Hoyt S. Vandenberg, all put down by divers and interests in the state of Florida, and the MV Captain Keith Tibbetts, and most recently the USS Kittiwake in the Cayman Islands. The success of those efforts has fueled the desire to send more mothballed military and other idled ships to the bottom as recreational, financial and ecological attractors. It is something that our diving community will continue to support, for divers to continue to enjoy, as history continues to serve.
On the morning of February 17, 1944, in a surprise attack by the United States, aircraft bombed Japanese warships and merchant vessels in Truk Lagoon, a strategic plot of wartime geography in the Central Pacific. The attack continued the next day and when it was over 52 ships and their crews were on the bottom. The destruction would have been far greater had the Japanese not seen U.S. reconnaissance planes overhead days earlier, anticipated the attack, and moved much of the fleet.
In 1945 the American government relocated the residents of the Bikini Atoll to another place in the Marshall Islands, to create an isolated spot and test the damage that could be inflicted by nuclear weapons. Among the tests, they wanted to see the effects on war vessels, and anchored a mock fleet in the blast area. Among the vessels sent to the bottom were the 880-foot (267-m) aircraft carrier USS Saratoga and, in a blast of irony, the Japanese battleship Nagota, from which Admiral Yamamoto directed the attack on Pearl Harbor.
November 23, 1984. A powerful storm ripped the Mercedes I from its temporary anchor in the Atlantic and landed the 194-foot (59-m) freighter up against a sea wall, literally next door to the Kennedy family’s Palm Beach, Florida, compound. The ship’s owners slithered off, and it took months for the state of Florida to have it pulled off the beach. Because of the unusual stranding, the moneyed neighborhood and the drama around the removal, the ship became a media celebrity. Just a few months later it began service as an artificial reef off the coast of Fort Lauderdale.
Shipwrecks, like people, have stories to tell. They rest where they are because of war, weather, malfunction, accident or by plan. A major allure of shipwrecks, certainly for divers who visit, are their histories. Certainly they all have interesting how-I-wound-up-on-the-bottom stories, but they have others. Many of the military ships that we are privileged to dive served in war. Others patrolled during peacetime to protect their country and the peace of others. Some ended up tracking space launches, or became spies, or were used as movie sets.
There are also very deep personal histories ascribed to each ship. Within each sailor who served, a military ship occupies a place usually reserved for a childhood home. For many it forged the rest of their life. For far too many, the ships became their grave.
And shipwrecks are surrounded by history. The push for America to stay ahead as a war power sent the Bikini fleet down. A total of 242 naval ships, 156 aircraft, 25,000 radiation-recording devices and some 5,400 goats, rats and pigs were subjected to the initial atmospheric nuclear blasts, which eventually numbered 23 over a 12-year period. Topping the chart was the monster of its time, a hydrogen bomb that vaporized three of the islands and spread radioactive debris over 50,000 square miles (130,000 sq km). In many ways the area is still reeling. The Bikini ships and the Ghost Fleet of Truk Lagoon essentially represent a placemark along man’s advancement from being savage to someday becoming civilized.
And finally, each wreck has an aftermath. Beyond any damage of war, or wear, or the sinking itself, ships are profoundly changed by the sea. They become cloaked in living biomass. Paradoxically colorful life camouflages the muzzles of guns as old ships become new environments. That part of a shipwreck’s history — the story to come — is the subject of the article in this edition as Alex Brylske talks about the ecological issues surrounding ships in their role as artificial reefs.
Quite a few ships have recently gone to reef by plan. In July 2000, the HMCS Yukon, a destroyer that served in the Royal Canadian Navy, was sunk by the San Diego Oceans Foundation after nearly 2,000 volunteers spent more than a year gutting and cleaning it for its role as a California artificial reef and dive site. Consider that, and you basically have the story of the USS Spiegel Grove, USS Oriskany and General Hoyt S. Vandenberg, all put down by divers and interests in the state of Florida, and the MV Captain Keith Tibbetts, and most recently the USS Kittiwake in the Cayman Islands. The success of those efforts has fueled the desire to send more mothballed military and other idled ships to the bottom as recreational, financial and ecological attractors. It is something that our diving community will continue to support, for divers to continue to enjoy, as history continues to serve.
Thursday, February 10, 2011
LIONS AND TIGERS AND BEARS
Written by Mark Young
Speaking of sharks, we may not have to fear them much more. Along with many of the ocean’s biggest predators, sharks are going away — basically, they are overfished. No wonder; it took from the beginning of time until the start of the 19th century for the first billion people to populate earth, now here we are at 6.9 billion. Fish just can’t keep up.
That’s not a problem for sustainable fish populations, where reproduction exceeds catch limits. But it is a problem when, for example, shark fin soup becomes the culinary rage in very populated places. That dish alone takes out an estimated 73 million sharks each year.
It’s scary down there. Professionals in this industry face that every day when trying to entice people to try diving. The people who raise their hands high enough to actually inquire about diving do so at their own peril. We don’t have a shot at the others, who know enough to never ask. Just ask divers how hard it is to convince their friends and relatives to give it a go.
We in the industry know too well about the “Jaws effect.” It’s a metaphor now, referring to what happened to the diving business in the mid-’70s, when the movie made people aware that to become certified was to become chum. Didn’t we hide that fact from the public for a long time? Then the movie came out. Then we had to wait out the downturn in business for the post-Jaws movie generation to come around. Well, then came Blockbuster. No matter. Since then, this sport has become dominated by daredevils. Why else the popularity of shark dives?
That’s not a problem for sustainable fish populations, where reproduction exceeds catch limits. But it is a problem when, for example, shark fin soup becomes the culinary rage in very populated places. That dish alone takes out an estimated 73 million sharks each year.
Did I actually say that it’s a problem? So getting rid of the scary stuff, why is that a bad thing? Of course everyone has opinions, and another view is that it’s the predators, not us, that should be in fear. Fish don’t fear so that’s ridiculous. Still, some divers, along with their science buddies, want to argue that healthy populations of ocean predators is actually a good thing. Alright, I misspoke; most divers and scientists believe it. These would be the same people, I suppose, who claim that diving in the same ocean with sharks and big grouper is safe. Still, let’s look at their case.
They argue that predators are essential to the ocean’s (the world’s) ecology. Everything is hunting something, and the “balance of nature” is a theory that ecological systems are basically in a state of stable equilibrium. But other scientists disagree. They point to observations that indicate predator and prey populations instead are in a constant state of disturbance and fluctuation, rather than in balance. They propose that equilibrium is illusory; more like a seesaw, where the size of prey and predator populations constantly change based on the relationship between populations and their food source, and differing external factors. I don’t know. Both theories sound like different ways for nature to achieve the same thing.
Except for one thing. Everyone seems to agree that the external factors are becoming more radical. According to reputable sources like the U.N. Food and Agriculture Organization, almost 70 percent of the world’s fisheries are fully to overexploited, depleted or in a state of collapse. And, as for the big boys, the ones that keep our potential divers away, about 90 percent of large predatory fish stocks, worldwide, are already gone.
Wait a minute. It is scary down there.
This editorial is in reference to the feature story, “Predators as Protectors,” that begins on Page 30, Dive Training magazine, March 2011
.
Saturday, February 5, 2011
SEA STATESMEN
Written by Mark Young
It took years of blank stares before the British followed Franklin’s advice about navigating the current, but that’s another story. Franklin became intrigued by the idea of a “stream” existing in the ocean. During his trips between the colonies and England he took measurements and notes about the water temperature, currents, water color and Gulf weed content. He knew that the current carries warm water from the south to the north, and that his measurements would mark the location of this “river in the ocean.” He also gathered data from Folger and other ship captains, learning enough to chart the Gulf Stream, and giving it the name by which it is known today. It’s a hoot that the first map of the Gulf Stream, published by Franklin in 1768, so closely mirrors today’s satellite images.
What comes to mind when you think of Benjamin Franklin? We know him as a statesman. One of our founding fathers, he helped frame and then signed the Constitution. He was a prolific author, a printer, an inventor (the furnace stove, bifocals … a carriage odometer?), political theorist, satirist and a philosopher. He formed the first lending library and fire department in Pennsylvania, published and wrote Poor Richard’s Almanack and The Pennsylvania Gazette, and had a major role in founding both the University of Pennsylvania and Franklin & Marshall College. Not bad for a guy whose formal schooling ended at the age of 10.
But your first thought might be the image of Franklin flying a kite during a thunderstorm; he was also a scientist (or, in his day, a natural philosopher). What many people don’t know, however, is that Franklin was also an early oceanographer. He became that by way of his position as deputy postmaster general of North America. It started with a question posed by the English Postal Authority. How, they asked, can American postal ships make the journey back from England to the colonies sometimes weeks faster than the English mail ships. Franklin consulted his whaling captain cousin, Timothy Folger. He learned of an ocean current that American and Spanish ship captains were aware of. They knew to sail with it traveling to England and stay out of it when returning to the colonies. The English mail packet captains were sailing dead against it.
It took years of blank stares before the British followed Franklin’s advice about navigating the current, but that’s another story. Franklin became intrigued by the idea of a “stream” existing in the ocean. During his trips between the colonies and England he took measurements and notes about the water temperature, currents, water color and Gulf weed content. He knew that the current carries warm water from the south to the north, and that his measurements would mark the location of this “river in the ocean.” He also gathered data from Folger and other ship captains, learning enough to chart the Gulf Stream, and giving it the name by which it is known today. It’s a hoot that the first map of the Gulf Stream, published by Franklin in 1768, so closely mirrors today’s satellite images. Franklin was by no means the first oceanographer. Although it is one of the newest fields of science, formally dating to organized expeditions in the late 19th century, oceanography can be traced back tens of thousands of years to the earliest seafarers who began observing the waves, tides and currents that carried their boats. Oceanography has essentially evolved from the need to find fish along coastlines, past the discovery that the Earth is not flat and can be navigated, past Franklin’s observations about currents, to today’s need to understand the place of the oceans in global climate.
The history of oceanography is as interesting as the discipline itself. In this issue, for our perspective as divers, author Robert Rossier examines what we know about tides, currents and waves, and most of what we know is from the observations made by Franklin and countless others who came before and after he turned his remarkable intellect to the sea.
Franklin’s unique genius was turning his observations to practical use. While the next guy to research electricity with a kite in a storm was killed doing it, Franklin invented the lightning rod. In the same way, the publication of his accumulated oceanographic findings, “Maritime Observations,” contains Franklin’s ideas for sea anchors, watertight compartments, catamaran hulls, shipboard lightning rods, and even a soup bowl that stays in place in rough seas. Oceanographic observation has done much for our lives, and we have benefited as divers — certainly for our ability to understand and continue learning about what we are most privileged to observe.
Thursday, December 23, 2010
THINGS WE NEVER KNEW
Written by Mark Young
It takes a drive through Kansas to really understand why it’s called the Sunflower State. In places, sunflower fields extend in every direction, and as far off as you can see. If you have never observed a large field of sunflowers, the sight is awesome beyond the expanse of yellow. You think at first that it’s because the plants are so much taller and larger than you imagined. Then it dawns on you. In stunning symmetry, they appear to be around the same height, and face in exactly the same direction. You may not even realize at first why they are aimed the same way, and that’s the next cool thing. Before they reach full flower, they face the sun as it comes up in the morning and the entire field rotates in grand unison as the sun moves across the sky, to the west by the end of the day. At the top of the Earth, where the sun never sets, scientists have observed sunflowers strangle themselves as they follow the sun circling the rim of the horizon. Any question where the plant got its name?
Even if you don’t know or care anything about sunflowers, this scant bit of information puts them in a whole new light (sorry). It can make you wonder about other things like, gee, what causes them to do that? Do they unwind at night? Do they follow the full moon, too? And even if these few facts don’t make you want to know more, it becomes great trivia for a dinner conversation.
This sidelong example shows that even seemingly simple things can become interesting with knowledge and a few basic facts. Now take something that actually interests us, like diving. As we become better informed the experience becomes more interesting and, in the process, in a way, so do we.
We have entered our 20th year publishing this magazine. There is so much about this activity and its environs to know, for anyone who wants to, and we felt that an educational publication that follows the light was more than needed. So we consider our tenure grateful confirmation that the interest in learning more about diving and what surrounds it is indeed pretty strong. People wondered early on if a magazine themed Dive Training would have enough to write about; there has certainly been enough content.
And it doesn’t run out. There is a long list of interesting dive-related topics that we would like to share with you in this edition, and in future editions. Take jellyfish, for example. We all know what they are but what really gives? This creature is complex in its simplicity. It turns out there is an awful lot to know about jellies, and author Greg Laslo takes us on another tour of a bizarre subject with the cover story that begins on Page 20.
We hope that after reading the article you will never look at jellyfish the same way again. Just like you may never look at sunflowers in quite the same way. So, do they unwind at night? When it comes to pondering what we know and what we don’t, perhaps the best questions revolve around the things that we are interested in and think we know, or never knew, but would like to learn much more about. To help make your diving experience complete, we will continue to keep you in the know about lots of different and interesting topics — lighting interest, we hope, for a few more decades.
Labels:
Dive Training Magazine,
Jellyfish,
Sunflowers
Monday, October 18, 2010
EVERYBODY'S BACKYARD
By Mark Young
European explorers led by Christopher Columbus were actually searching for a sea route to Asia when by luck they discovered the Caribbean and the Americas. This wasn’t so lucky for the various native populations, however; they couldn’t defend themselves against conquest, but the most devastating import was biological. Where the people of the three known continents had long been exposed to each other’s diseases and developed a strong immunity, the cultures that the “Columbuses” discovered were powerless against the import of smallpox, measles and influenza. Mere contact killed millions of indigenous people.
European explorers led by Christopher Columbus were actually searching for a sea route to Asia when by luck they discovered the Caribbean and the Americas. This wasn’t so lucky for the various native populations, however; they couldn’t defend themselves against conquest, but the most devastating import was biological. Where the people of the three known continents had long been exposed to each other’s diseases and developed a strong immunity, the cultures that the “Columbuses” discovered were powerless against the import of smallpox, measles and influenza. Mere contact killed millions of indigenous people.
In a sense you could say that throughout history subsets of man have been an invasive species. And wherever we humans have gone, nature has been along for the ride.
People tend to think of “invasive species” only in negative terms, but the phrase has several degrees of definition. Toward the “OK” scale it refers to “introduced species or nonindigenous species that are rapidly expanding outside of their native range.” A not-so-OK connotation is, “alien species whose introduction or spread threatens the environment, the economy, and/or society, including human health.”
Degrees of the definition are appropriate. For example, an argument can be made that the introduction of most exotic species has richly enhanced biodiversity. Consider traveling plants; more than 4,000 species introduced into North America during the past 400 years make up nearly 20 percent of our current plant biodiversity. And, with no evidence, according to some biologists, that a single resident species has been driven to extinction. In other words, with some pesky exceptions, plants that invade fit in.
As divers we tend to think negatively about the arrival of nonindigenous marine life, yet the opening of the Suez Canal in 1869 introduced 250 new fish species into the Mediterranean from the Red Sea, reportedly resulting in only a single extinction. So there’s that.
On the other hand, who wants the Burmese python at the top of the Everglades food chain? (Have you seen the YouTube video of the snake that exploded while digesting an alligator?) Their numbers in the Glades are estimated at more than 100,000, growing fast, and pose a threat to natural balance in a truly spectacular ecosystem — all because a few pets outgrew their welcome. Perhaps the Nile monitor lizard, an African heavy that grows to 7 feet (2 m) in length can give the pythons a run for the top; they’ve also established Florida residency. Kind of makes the U.S. invasions of zebra mussels and Asian carp seem tame.
This month’s cover feature is an update on the Atlantic/Caribbean invasion of lionfish, another pet let loose. There’s no debate that this has the possibility of an environmental disaster. One hope against it is the commercial potential of lionfish as a culinary dish; that would at least put something above them in the food chain. Another possibility is whatever mechanism keeps them in check in their far-Pacific homeland, something that is being studied to determine.
However this plays out, we’re about to see in the extreme how well natural balance can occur where it must, while we humans continue to move nature past the geographic boundaries that once contained the Earth’s biota, and into our own backyards.
Labels:
Invasive species,
Lionfish
Saturday, September 18, 2010
TIES THAT BIND
By Mark Young
A memory is what is left when something happens and does not completely unhappen.
~Edward de Bono
During a business trip to Florida I wound up near where I used to live, and stopped into a small airport where I kept a plane for a quite a while. I’m not quite sure, after nearly 20 years, why I decided to visit the flight center where I was based, but it called me back.
I’m guessing that the flight instructor behind the counter was in diapers when I was a customer there. We had a great conversation and some laughs, me sharing stories about how the place was, she telling how it is, and the old wooden flight center felt like home. Just the smell of the place summoned fond memories, and the experience was nicely nostalgic.
It's surprising how much memory is built around things unnoticed at the time. What from today will cause you to look back tomorrow and smile? You might just be in that place; you were probably introduced to this magazine at your local dive center and someday that store, the people you meet there and the experiences that you collect might mark a considerable time of your life. Most store owners and dive instructors are in this business to pass on to you what has such importance to them, so connecting you to diving, and a lot of great things to remember, should be natural. But sometimes even important things need a solid introduction to help them stick.
I mention this because of how the initial introduction to diving has changed. Not many years ago, people who learned to dive went through about 40 hours of face-to-face instruction. That amount of classroom and pool time allowed instructors and students to get to know one another, and a provided good conduit for the passion of diving to transfer. At some point, the industry decided that so much of a commitment to scheduled time was limiting participation, so they set out to shorten it with home study options to attract more people. As a result, some of today’s students may not spend as much time with an instructor outside of the pool sessions. But are they missing an important connection? Did we abbreviate ourselves out of the bonding that comes with spending time?
I wondered about that as I read this issue’s Instructor Tips column about the positive learning effects of instructor storytelling. It’s a reminder that much of learning happens outside the lines of a book or the glare of a screen. Observing that young flight instructor, I imagined how well she must be bonding her students to the excitement and the possibilities of aviation. I thought of her importance as a mentor, and her ability to inspire her students through the emotional desert of dry textural material.
I remember that learning to dive was an escape from my cubicled world; not a drag at all. Learning doesn’t just involve what you know; it inspires what you do with what you know. It is the emotional, not textural information that forms the strongest attachment. There is terrific benefit to being surrounded early on by the diving environment, the enthusiasm of a good instructor and sharing the excitement, anticipation and even some of the apprehension with other people who are learning too.
We in the industry want to connect you. It is important for you to help establish the connection too, especially if you don’t feel that it exists for you as it should. You don’t want to let this experience unhappen. Stop by your dive center to linger a while, and you might just find yourself stopping back in 20 years, and finding memories.
A memory is what is left when something happens and does not completely unhappen.
~Edward de Bono
During a business trip to Florida I wound up near where I used to live, and stopped into a small airport where I kept a plane for a quite a while. I’m not quite sure, after nearly 20 years, why I decided to visit the flight center where I was based, but it called me back.
I’m guessing that the flight instructor behind the counter was in diapers when I was a customer there. We had a great conversation and some laughs, me sharing stories about how the place was, she telling how it is, and the old wooden flight center felt like home. Just the smell of the place summoned fond memories, and the experience was nicely nostalgic.
It's surprising how much memory is built around things unnoticed at the time. What from today will cause you to look back tomorrow and smile? You might just be in that place; you were probably introduced to this magazine at your local dive center and someday that store, the people you meet there and the experiences that you collect might mark a considerable time of your life. Most store owners and dive instructors are in this business to pass on to you what has such importance to them, so connecting you to diving, and a lot of great things to remember, should be natural. But sometimes even important things need a solid introduction to help them stick.
I mention this because of how the initial introduction to diving has changed. Not many years ago, people who learned to dive went through about 40 hours of face-to-face instruction. That amount of classroom and pool time allowed instructors and students to get to know one another, and a provided good conduit for the passion of diving to transfer. At some point, the industry decided that so much of a commitment to scheduled time was limiting participation, so they set out to shorten it with home study options to attract more people. As a result, some of today’s students may not spend as much time with an instructor outside of the pool sessions. But are they missing an important connection? Did we abbreviate ourselves out of the bonding that comes with spending time?
I wondered about that as I read this issue’s Instructor Tips column about the positive learning effects of instructor storytelling. It’s a reminder that much of learning happens outside the lines of a book or the glare of a screen. Observing that young flight instructor, I imagined how well she must be bonding her students to the excitement and the possibilities of aviation. I thought of her importance as a mentor, and her ability to inspire her students through the emotional desert of dry textural material.
I remember that learning to dive was an escape from my cubicled world; not a drag at all. Learning doesn’t just involve what you know; it inspires what you do with what you know. It is the emotional, not textural information that forms the strongest attachment. There is terrific benefit to being surrounded early on by the diving environment, the enthusiasm of a good instructor and sharing the excitement, anticipation and even some of the apprehension with other people who are learning too.
We in the industry want to connect you. It is important for you to help establish the connection too, especially if you don’t feel that it exists for you as it should. You don’t want to let this experience unhappen. Stop by your dive center to linger a while, and you might just find yourself stopping back in 20 years, and finding memories.
Tuesday, August 10, 2010
EDITORIAL September 2010: ENDLESS DIVING
By Mark Young
I know a couple who fell so hard for diving that they racked up close to 200 dives in just their first year. Living in South Florida made that easy. She would pick him up after a business trip, and head straight from the airport to a midnight dive. They dove the local charters; they bought their own boat which, since they were always under it, they renamed Two Down; they went east to the Bahamas, south to the Keys and into the Caribbean. They couldn’t get enough.
Connect that to this. The nation’s highway system was built with materials that were mined along the way. The abandoned quarries filled with groundwater and many were reclaimed as recreation areas. Divers came along and populated the bottoms with things like airplanes of all sizes, helicopters, school buses, semitrailers, busses, boats and things you wouldn’t imagine. Some of the quarries are absolutely beautiful with a wide range of aquatic life, forests and sheer rock walls. Many have camping facilities and some even host outdoor music concerts. Their proximity to the highways that they built provides divers with easy access. As you would guess lots of quarry diving goes on in the United States.
Lots of other diving goes on too. Within our borders there is endless spring, lake, river and coastal diving. Heck, you can even dive in many of the nation’s aquariums, a theme park and in a major Las Vegas show. Local dive outings are an important business and social component for many of the nation’s dive centers.
The purpose of this editorial is to call your attention to a resource that we haven’t talked about much. It is the local diving component of our magazine and website. Many people who get certified limit their diving to foreign trips, and some of that is simply because they aren’t aware of the opportunities that are close by. It’s why we introduce two local diving spots in these pages each month. The couple that I talked about was also the inspiration for the “Diving USA: Dive Sites Across America” section at dtmag.com. That they were so nuts about diving but didn’t know about nearby dive sites raises the odds that lots of others don’t know about theirs either, especially newer divers.
For a number of years we have been compiling our local dive writings on the website, and now have hundreds of sites pinpointed on the map so that you can see the proximity and read about diving’s local opportunities. It is the most visited area of our website, and we encourage you to use it.
A great thing about diving is that it happens everywhere. Not many activities can match the experiences, the diversity, and the friendships that diving presents. Diving is literally available worldwide in such wide range. And whether you live in California or Arkansas, it is also close by.
Care to comment?
We add locations to the local diving site at http://www.dtmag.com/ monthly. If you come across a place that we haven't covered. or would like to tell others about a local site that you visit, post your comments below.
I know a couple who fell so hard for diving that they racked up close to 200 dives in just their first year. Living in South Florida made that easy. She would pick him up after a business trip, and head straight from the airport to a midnight dive. They dove the local charters; they bought their own boat which, since they were always under it, they renamed Two Down; they went east to the Bahamas, south to the Keys and into the Caribbean. They couldn’t get enough.But there was more to get, like diving to the North. Any clue about Florida’s springs, just a few hours away, escaped them for years or they would have been there, next chance. He recalls that regretfully, like they were robbed.
Lots of other diving goes on too. Within our borders there is endless spring, lake, river and coastal diving. Heck, you can even dive in many of the nation’s aquariums, a theme park and in a major Las Vegas show. Local dive outings are an important business and social component for many of the nation’s dive centers.
The purpose of this editorial is to call your attention to a resource that we haven’t talked about much. It is the local diving component of our magazine and website. Many people who get certified limit their diving to foreign trips, and some of that is simply because they aren’t aware of the opportunities that are close by. It’s why we introduce two local diving spots in these pages each month. The couple that I talked about was also the inspiration for the “Diving USA: Dive Sites Across America” section at dtmag.com. That they were so nuts about diving but didn’t know about nearby dive sites raises the odds that lots of others don’t know about theirs either, especially newer divers.
For a number of years we have been compiling our local dive writings on the website, and now have hundreds of sites pinpointed on the map so that you can see the proximity and read about diving’s local opportunities. It is the most visited area of our website, and we encourage you to use it.
A great thing about diving is that it happens everywhere. Not many activities can match the experiences, the diversity, and the friendships that diving presents. Diving is literally available worldwide in such wide range. And whether you live in California or Arkansas, it is also close by.
Care to comment?
We add locations to the local diving site at http://www.dtmag.com/ monthly. If you come across a place that we haven't covered. or would like to tell others about a local site that you visit, post your comments below.
Labels:
Lakes,
Local Diving,
Quarries
Monday, August 9, 2010
NO DUMB QUESTIONS, SEPTEMBER 2010: Diving After Flying, How Much is Too Much and Altitude Issues
By Alex Brylske
Q: Joe Plocinski wrote with a question that’s rarely considered concerning flying and diving. “I would like to know if there is a recommendation or rule of thumb for any ‘ground time’ interval between flying and making your first dive? During our certification class we were told that the recommended surface interval for flying after diving is 12 hours after a single dive, and 18 hours after repetitive/multiday diving. However, I do not recall hearing anything about diving after flying, or if there are any possible effects on the body. We will be vacationing in the Caribbean, arriving early afternoon and was wondering if it would be OK to get a dive in that day?”
Q: Deidre Levin had a question that I wish more divers considered. “I was on a live-aboard dive trip recently where most of us made between 20 and 25 dives during the five days we were aboard. One evening toward the end of the trip, our discussion centered on an issue that I’ve never seen addressed in any publication or discussed by any diving authority. But it seems like a simple and important matter. Can a diver do too much diving? I’m not talking about decompression sickness. Assuming that’s not an issue — the person feels perfectly fine — is there still a point when, like most things, there’s too much of a good thing?”
A: You have entered a very interesting realm of discussion, and you’re right; it’s rarely if ever addressed. Perhaps the reason almost no one ever talks about it is because we know so little about the long-term effects of diving in recreational divers.
It is, however, well documented that some commercial divers do suffer long-term effects. Hearing loss is one common ailment. However, another is a lesser-known condition called dysbaric osteonecrosis, literally, “bone death due to uneven pressure.” While to my knowledge it hasn’t been proven conclusively, many medical authorities blame this disorder on the extreme and continued conditions encountered by commercial divers, especially those who have a lot of deep-saturation experience. (By the way, it’s even been reported in sperm whales.)
The good news is that it’s believed that recreational divers spend far too little time underwater in their careers for this to be of any concern. However, there has been some evidence that dive professionals who spend extreme amounts of time at depth, such as divemasters and instructors, may be susceptible.
Still, my concern gets back to the issue that you dismissed: decompression. Even if someone does not manifest any symptoms of bends, we really don’t know what the cumulative effect may be. We do know that silent bubbles develop commonly in recreational divers, and that they most often resolve without any problem. But could they have a cumulative effect over many years or decades? Could age have any effect on this mechanism? Or, could more diving actually help build some form of immunity to bends? We just don’t know.
Personally, I’m a cautious person. And, probably like a lot of folks, I’ve gotten more so as I’ve gotten older. Now, in my diving, I almost never make more than two dives a day, and three is the absolute limit. I know that may sound unduly conservative — and I do have the advantage of diving just about any day of the week I care to — but that’s my decision. So, does the concept of too much of a good thing apply to diving? Probably, but we have no idea where that limit lies, and I personally don’t plan to provide any evidence.
Q: Dave Lewis sent in a question about altitude and diving. “I wonder about the oxygen content of compressed air in a scuba tank when it is filled at altitude where the lack of oxygen tires out hikers. Do dive centers at altitude enrich compressed air to normal levels?”
A: Your confusion is understandable given that hypoxia (low oxygen) is a common concern for anyone at high altitude. After all, who hasn’t watched a film about pilots or mountain climbers in which they didn’t see oxygen masks at the ready? As we’re reminded in the required announcement prior to every flight we’ve taken, supplemental oxygen is readily available in the event of loss of cabin pressure.
But let’s think more closely about this for a second. The concentration of oxygen in the atmosphere everywhere on the planet is 21 percent. (If you’re a stickler for accuracy it’s really 20.946 percent.) What’s more, that value holds true no matter where you are in the atmosphere, be it at the surface or about to step on the peak of Mount Everest. That means no matter where you fill a scuba tank, as long as it is somewhere on Earth, it will always contain 21 percent oxygen (assuming it’s not a nitrox fill, of course). So, if the oxygen fraction of air is always the same, where does all the concern over hypoxia come from?
The answer involves not pressure, but percentage. The physiological effect a gas has on our body depends not on the fraction of a gas within the mixture, but on the actual number of molecules we breathe. This is a function of the partial pressure of the gas in question within a gas mixture. An example will illustrate the point.
If you’re a nitrox diver you know that the oxygen partial pressure (ppO) at the surface, 1 atmosphere, is 0.21 ATA (reflecting its gas fraction, 0.21 x 1.0 = 0.21). At 2 atmospheres (33 feet [10 m]), where the pressure doubles, this increases to 0.42 ATA (0.21x 2.0 = 0.42). However, if you ascend in the atmosphere to a height of about five kilometers (16,400 feet), the pressure will halve. This means the oxygen partial pressure drops to 0.105 ATA (0.21 x 0.05 = 0.105). While we’d experience no problem whatsoever at the surface or at 33 feet [10 m], at altitude this low value is insufficient to maintain consciousness and we’d black out. Remember, however, that the percentage of oxygen in every case has not changed; it’s always 21 percent.
Q: Patti W. writes, “What should I use to rinse the inside of my buoyancy compensator (BC) after diving in salt water?”
A: First of all, it’s always good to give your gear a quick rinse in fresh water after an ocean dive, to rinse away the seawater. If you aren’t in the habit of rinsing your gear, you should be, because salt crystals that form on your gear when it dries can abrade surfaces, wear out threads and cause corrosion. A longer soaking at home after a dive trip — ideally in warm water — is also recommended.
Now, to the question of rinsing the inside of the BC, I’ve never actually used anything but fresh water.
Some divers use the eco-friendly product Simple Green® or similar mild detergents. There are also a few commercial products available just for rinsing scuba gear, so ask at your local dive center. Some have speculated that because a BC might be inflated orally, its interior should be disinfected periodically. So, a very mild bleach solution could be used for this purpose. In addition, some rebreather manufacturers offer nonbleaching disinfectant solutions, which are a better choice but, again, I think that good-old water should do the trick.
Q: Joe Plocinski wrote with a question that’s rarely considered concerning flying and diving. “I would like to know if there is a recommendation or rule of thumb for any ‘ground time’ interval between flying and making your first dive? During our certification class we were told that the recommended surface interval for flying after diving is 12 hours after a single dive, and 18 hours after repetitive/multiday diving. However, I do not recall hearing anything about diving after flying, or if there are any possible effects on the body. We will be vacationing in the Caribbean, arriving early afternoon and was wondering if it would be OK to get a dive in that day?”A:You bring up an interesting point that’s rarely discussed, though given how common your experience is, it certainly should be addressed more often. Most informed divers assume that flying before diving poses no problem. In fact, you can make a logical argument that diving soon after a flight could impose a safety factor because you start the dive with less nitrogen in your tissues than you would if you were saturated at sea-level pressure. In theory, this might make sense. In practice, however, it might lead you to a recompression chamber.
The issue really isn’t the amount of nitrogen in your body, but rather the fact that a diver arriving at a dive resort after several hours of flying is not likely to be in his or her best shape. The stresses of the airplane cabin air, dehydration, restricted circulation from sitting in a confined position, and general fatigue from the journey are all factors that could place the diver under an increased — not decreased — risk for decompression illness. The best advice is to avoid diving until you are completely recovered and rested from the stress of flying to your favorite resort. Of course, that means there can be no hard-and-fast rule. Every individual is different, the actual stress of a flight depends on many factors, and only you know your body well enough to make the final decision of when it has recovered. Do many divers make their first dive just after unpacking their bags? Of course. Do some of them get the bends or incur other problems? Again, yes. Was their flight a factor in the outcome? No one knows. Perhaps a good compromise is that, if you do decide to dive immediately on arrival, make sure it’s a shallow, easy one.
Q: Deidre Levin had a question that I wish more divers considered. “I was on a live-aboard dive trip recently where most of us made between 20 and 25 dives during the five days we were aboard. One evening toward the end of the trip, our discussion centered on an issue that I’ve never seen addressed in any publication or discussed by any diving authority. But it seems like a simple and important matter. Can a diver do too much diving? I’m not talking about decompression sickness. Assuming that’s not an issue — the person feels perfectly fine — is there still a point when, like most things, there’s too much of a good thing?”
A: You have entered a very interesting realm of discussion, and you’re right; it’s rarely if ever addressed. Perhaps the reason almost no one ever talks about it is because we know so little about the long-term effects of diving in recreational divers.
It is, however, well documented that some commercial divers do suffer long-term effects. Hearing loss is one common ailment. However, another is a lesser-known condition called dysbaric osteonecrosis, literally, “bone death due to uneven pressure.” While to my knowledge it hasn’t been proven conclusively, many medical authorities blame this disorder on the extreme and continued conditions encountered by commercial divers, especially those who have a lot of deep-saturation experience. (By the way, it’s even been reported in sperm whales.)
The good news is that it’s believed that recreational divers spend far too little time underwater in their careers for this to be of any concern. However, there has been some evidence that dive professionals who spend extreme amounts of time at depth, such as divemasters and instructors, may be susceptible.
Still, my concern gets back to the issue that you dismissed: decompression. Even if someone does not manifest any symptoms of bends, we really don’t know what the cumulative effect may be. We do know that silent bubbles develop commonly in recreational divers, and that they most often resolve without any problem. But could they have a cumulative effect over many years or decades? Could age have any effect on this mechanism? Or, could more diving actually help build some form of immunity to bends? We just don’t know.
Personally, I’m a cautious person. And, probably like a lot of folks, I’ve gotten more so as I’ve gotten older. Now, in my diving, I almost never make more than two dives a day, and three is the absolute limit. I know that may sound unduly conservative — and I do have the advantage of diving just about any day of the week I care to — but that’s my decision. So, does the concept of too much of a good thing apply to diving? Probably, but we have no idea where that limit lies, and I personally don’t plan to provide any evidence.
Q: Dave Lewis sent in a question about altitude and diving. “I wonder about the oxygen content of compressed air in a scuba tank when it is filled at altitude where the lack of oxygen tires out hikers. Do dive centers at altitude enrich compressed air to normal levels?”
A: Your confusion is understandable given that hypoxia (low oxygen) is a common concern for anyone at high altitude. After all, who hasn’t watched a film about pilots or mountain climbers in which they didn’t see oxygen masks at the ready? As we’re reminded in the required announcement prior to every flight we’ve taken, supplemental oxygen is readily available in the event of loss of cabin pressure.
But let’s think more closely about this for a second. The concentration of oxygen in the atmosphere everywhere on the planet is 21 percent. (If you’re a stickler for accuracy it’s really 20.946 percent.) What’s more, that value holds true no matter where you are in the atmosphere, be it at the surface or about to step on the peak of Mount Everest. That means no matter where you fill a scuba tank, as long as it is somewhere on Earth, it will always contain 21 percent oxygen (assuming it’s not a nitrox fill, of course). So, if the oxygen fraction of air is always the same, where does all the concern over hypoxia come from?
The answer involves not pressure, but percentage. The physiological effect a gas has on our body depends not on the fraction of a gas within the mixture, but on the actual number of molecules we breathe. This is a function of the partial pressure of the gas in question within a gas mixture. An example will illustrate the point.
If you’re a nitrox diver you know that the oxygen partial pressure (ppO) at the surface, 1 atmosphere, is 0.21 ATA (reflecting its gas fraction, 0.21 x 1.0 = 0.21). At 2 atmospheres (33 feet [10 m]), where the pressure doubles, this increases to 0.42 ATA (0.21x 2.0 = 0.42). However, if you ascend in the atmosphere to a height of about five kilometers (16,400 feet), the pressure will halve. This means the oxygen partial pressure drops to 0.105 ATA (0.21 x 0.05 = 0.105). While we’d experience no problem whatsoever at the surface or at 33 feet [10 m], at altitude this low value is insufficient to maintain consciousness and we’d black out. Remember, however, that the percentage of oxygen in every case has not changed; it’s always 21 percent.
Q: Patti W. writes, “What should I use to rinse the inside of my buoyancy compensator (BC) after diving in salt water?”
A: First of all, it’s always good to give your gear a quick rinse in fresh water after an ocean dive, to rinse away the seawater. If you aren’t in the habit of rinsing your gear, you should be, because salt crystals that form on your gear when it dries can abrade surfaces, wear out threads and cause corrosion. A longer soaking at home after a dive trip — ideally in warm water — is also recommended.
Now, to the question of rinsing the inside of the BC, I’ve never actually used anything but fresh water.
Some divers use the eco-friendly product Simple Green® or similar mild detergents. There are also a few commercial products available just for rinsing scuba gear, so ask at your local dive center. Some have speculated that because a BC might be inflated orally, its interior should be disinfected periodically. So, a very mild bleach solution could be used for this purpose. In addition, some rebreather manufacturers offer nonbleaching disinfectant solutions, which are a better choice but, again, I think that good-old water should do the trick.
Monday, July 19, 2010
EDITORIAL, AUGUST 2010: CANDY COATED DIVERS?
By Cathryn Castle Whitman
I got an e-mail from a reader recently, expressing her concern over a photograph that appeared in a recent issue of Dive Training. Every now and then a “no-no” photo slips past us — maybe the diver is wearing his snorkel on the right side of the mask instead of the left or a way-too-long weight belt is shown dangling. It happens sometimes. And readers take us to task. But this time, rather than point out the problem, the reader simply asked, “What’s wrong with this picture?”
I scanned it carefully, looking for the glaring error that got overlooked. The photo was of a group of wet-suit-clad divers preparing to gear up for a dive. In it, no one had a snorkel attached to a mask incorrectly, or a too-long belt. The scuba units were stowed properly and no one, heaven forbid, had their mask perched on top of their head, or some other obvious “no-no” likely to set off a letter to the editor.
I didn’t get it.
So, I offered to discuss the reader’s concern in a phone conversation. She e-mailed her phone number, I called, and after we exchanged a few polite greetings she asked, “So, what’s wrong with this picture? Do you get it yet?”
I stared harder. Still, nothing jumped out.
“They’re all obese. Or at least overweight.
NO DUMB QUESTIONS, AUGUST 2010: Pacemakers and Diving, Advanced Training, The Effect of Crude Oil on Corals
Q:Thomas McGill had a follow-up question regarding a feature article I did a few months ago called “The Telltale Heart” (April 2010). Could you expand on some information on diving with pacemakers for me? The article states, in part, ‘there is no reason why a pacemaker should automatically disqualify anyone from recreational diving.’ I and the pacemaker manufacturers seem to agree with this. The article goes on, ‘the real issue is why the patient needs a pacemaker. If the device was implanted solely to correct a problem with the rhythm of the heart, then the candidate can dive. If, however, the heart showed other problems or disease, then the pacemaker candidate should not dive.’ Could you expand on that last sentence for me? My pacemaker was installed because of a slow heart rate. Otherwise, I have no heart difficulties, and I do maintain myself in reasonable physical condition for diving.”
A:Thomas, sorry I wasn’t able to answer your question fully in my earlier feature. The issue is not one of technology but the same concern we have with any medical condition: Might the underlying problem for which the pacemaker was installed affect one’s fitness to participate in scuba diving?
Pacemakers are installed to address abnormalities in the heart’s electrical conduction system. Often, though not always, patients with such abnormalities have some form of cardiac disease as the underlying cause of their abnormality. For example, congenital heart disease, certain valvular heart diseases (aortic stenosis with valvular and AV-ring calcification), cardiomyopathy and coronary heart disease all may be associated with chronic conduction system abnormalities. Any of these conditions can mean that an individual may lack the cardiovascular fitness required to safely participate in diving. In fact, according to the Divers Alert Network, the most common reason for a pacemaker is underlying ischemic heart disease. This is a huge concern in diving because an increasing number of recreational diving fatalities each year are attributable to coronary artery disease. Another complicating factor is that diving often takes place in remote locations far from facilities that provide emergency cardiac care.
In your case, it appears that there was no underlying heart disease, and the pacemaker was installed solely to correct an arrhythmia problem. Assuming you have sufficient exercise tolerance, you are exactly the type of individual who need not be disqualified from diving.
One other issue I also failed to address in the feature involves the pacemaker itself. Any device used while diving must be up to functioning in the underwater environment. Therefore, the pacemaker must be rated to perform at least to a depth of 130 feet (39 m), and must operate satisfactorily during conditions of wide pressure changes, such as during ascent and descent.
Labels:
Advanced Dive Training,
Gulf Oil Spill,
Pacemakers
BUDDY LINES: LETTERS TO THE EDITOR, AUGUST 2010
Thoughts and feedback on what constitutes a safe diver, tipping your dive crew, adaptive scuba diving, and remembering Andy Letourneau, all in this month's edition of "Buddy Lines."
Sunday, June 6, 2010
EDITORIAL, JULY 2010: SPILL, BABY, SPILL
By Cathryn Castle Whitman
Thursday, May 13, 2010
EDITORIAL, JUNE 2010: WHERE THE BUCK STOPS
By Alex Brylske
I dive off charter boats frequently, so I have lots of opportunities to observe divers. I see good divers and bad, experienced pros and neophytes, and locals as well as tourists. With such variety, it’s tough to draw any uniform conclusions. But there does seem to be a trend and, from my vantage point, it’s not a good one: My admittedly unscientific assessment tells me that divers are assuming less and less responsibility for their own well-being. In fairness, it’s not really restricted to divers; it’s been a societal trend for some time.
When something goes wrong the answer is to blame anyone but ourselves. Abandoning responsibility even happens when nothing goes wrong, as I saw on a recent dive.
I dive off charter boats frequently, so I have lots of opportunities to observe divers. I see good divers and bad, experienced pros and neophytes, and locals as well as tourists. With such variety, it’s tough to draw any uniform conclusions. But there does seem to be a trend and, from my vantage point, it’s not a good one: My admittedly unscientific assessment tells me that divers are assuming less and less responsibility for their own well-being. In fairness, it’s not really restricted to divers; it’s been a societal trend for some time.
When something goes wrong the answer is to blame anyone but ourselves. Abandoning responsibility even happens when nothing goes wrong, as I saw on a recent dive.
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Harry Truman,
nitrox,
Responsibility
Friday, April 9, 2010
EDITORIAL, MAY 2010: ISN'T IT TIME?
By Alex Brylske
Photo by Joseph C. Dovala
(Readers, please comment at bottom of editorial)
Unless you were on some other planet recently, you no doubt heard about the recent event at Orlando’s SeaWorld in which a trainer was killed by an orca. Clearly, it was a tragic situation made worse in that it was apparently a very public spectacle. And unlike what was initially reported by authorities, the victim did not fall into the pool, but was grabbed and dragged into the water by the whale. Some were surprised that the animal wasn’t put down, as would have been the case with a dog; and many even expressed alarm when it was made public that this was the third fatality involving the whale, Tilikum. (Although, in fairness, it’s far from certain that he was the cause of one of those deaths.) Personally, I was heartened to learn that Tilikum wasn’t euthanized. It also made me question the purpose and true cost of turning marine mammals into circus performers.
Photo by Joseph C. Dovala
(Readers, please comment at bottom of editorial)
Unless you were on some other planet recently, you no doubt heard about the recent event at Orlando’s SeaWorld in which a trainer was killed by an orca. Clearly, it was a tragic situation made worse in that it was apparently a very public spectacle. And unlike what was initially reported by authorities, the victim did not fall into the pool, but was grabbed and dragged into the water by the whale. Some were surprised that the animal wasn’t put down, as would have been the case with a dog; and many even expressed alarm when it was made public that this was the third fatality involving the whale, Tilikum. (Although, in fairness, it’s far from certain that he was the cause of one of those deaths.) Personally, I was heartened to learn that Tilikum wasn’t euthanized. It also made me question the purpose and true cost of turning marine mammals into circus performers.
Wednesday, April 7, 2010
NO DUMB QUESTIONS, MAY 2010: A PHYSICS PRIMER FOR SCUBA DIVERS
by Alex Brylske
Photo by Joseph C. Dovala
Readers please submit comments at the end of the article.
Q: Al Pinzon had a question about tank capacity. “My wife and I are recently certified Open Water divers. I use an 80 tank and my wife uses a 50. Our question is how do we know exactly how much air is left in our tanks at the conclusion of a dive? Even though each of our submersible pressure gauges (SPGs) may both read 500 psi, we know we don’t have the same amount of air. So how do we determine the amount of air left in the smaller tank so my wife doesn’t risk running out of air?”
A: There’s a very simple way to convert psi to cubic feet. Just take the capacity of the cylinder in question and divide it by its maximum working pressure. The product is, in essence, how many cubic feet of air is accounted for by each “psi.” Let’s take the standard 80-cubic- foot cylinder as an example. By dividing 80 (its maximum capacity) by 3,000 (its maximum-rated pressure) we get 0.0266. In other words, we can assume that each psi of pressure accounts for 0.0266 cubic feet of air. Thus, if the tank is filled to only 2,000 psi, rather than its maximum 80 cubic feet, it contains only 53.2 cubic feet (2,000 X 0.0266).
In the case of your wife’s 50-cubic-foot tank, the value is 0.0166 (or if she uses the more standard 63 cubic footer it’s 0.0210). Therefore, if you each end your dive with 500 psi remaining, you have 13.3 cubic feet of air left but your wife has only 8.3 cubic feet.
Of course, even though your wife would have less air remaining, it’s likely she also uses less air, which is why you can both plan to exit the water with 500 psi. So, with all things being equal, you’d both have about the same usable reserve in terms of time underwater at the same depth.
More questions after the break...
Photo by Joseph C. Dovala
Readers please submit comments at the end of the article.
Q: Al Pinzon had a question about tank capacity. “My wife and I are recently certified Open Water divers. I use an 80 tank and my wife uses a 50. Our question is how do we know exactly how much air is left in our tanks at the conclusion of a dive? Even though each of our submersible pressure gauges (SPGs) may both read 500 psi, we know we don’t have the same amount of air. So how do we determine the amount of air left in the smaller tank so my wife doesn’t risk running out of air?”
A: There’s a very simple way to convert psi to cubic feet. Just take the capacity of the cylinder in question and divide it by its maximum working pressure. The product is, in essence, how many cubic feet of air is accounted for by each “psi.” Let’s take the standard 80-cubic- foot cylinder as an example. By dividing 80 (its maximum capacity) by 3,000 (its maximum-rated pressure) we get 0.0266. In other words, we can assume that each psi of pressure accounts for 0.0266 cubic feet of air. Thus, if the tank is filled to only 2,000 psi, rather than its maximum 80 cubic feet, it contains only 53.2 cubic feet (2,000 X 0.0266).
In the case of your wife’s 50-cubic-foot tank, the value is 0.0166 (or if she uses the more standard 63 cubic footer it’s 0.0210). Therefore, if you each end your dive with 500 psi remaining, you have 13.3 cubic feet of air left but your wife has only 8.3 cubic feet.
Of course, even though your wife would have less air remaining, it’s likely she also uses less air, which is why you can both plan to exit the water with 500 psi. So, with all things being equal, you’d both have about the same usable reserve in terms of time underwater at the same depth.
More questions after the break...
Tuesday, April 6, 2010
BUDDY LINES: LETTERS TO THE EDITOR, MAY 2010
Readers may add additional comments at the end of this article.
SOLO DIVING SHOULD BE EMBRACED
I am in total agreement with your editorial, “To Buddy or Not to Buddy,” Dive Training, March 2010, and would like to thank you for this long overdue discussion. I have been diving since 1968 and was an instructor in the earlier days of scuba diving. My interest in underwater photography and videography brought me to many international open waters. I appreciate the evolutionary technical, physiological and teaching improvements, however, I think this at times forced “buddy system” has reached an excessive level.
The increased focus on “self-reliance” would necessitate a better understanding of one’s own equipment and capabilities, and it would not degrade any safety procedures.
The attitude in existence today forces one to pretend to agree to the “buddy system,” which oftentimes leads to the “once we are underwater I’ll do it my way” situation. The situation described in the article creates uncomfortable and resentful feelings and is not a positive experience. The “solo diver” should be accepted and accommodated, especially since everyone signs all legal responsibility “absolution” papers at any and all scuba diving activities, from “air fills,” to rental equipment, to boat dives.
Heinz W. Blaume
South Lake Tahoe, California
Thursday, March 18, 2010
THE LONG AND SHORT OF IT
By Alex Brylske
Recently I saw an ad from a dive center proudly announcing, “Learn to Dive in only three days!” It’s not that big of a deal, given that many dive centers have for years been offering programs to train divers in as little as four days (normally over two weekends). But it got me thinking about how much diving has changed over the years, and whether it’s all been for the good.
To provide some perspective, when I learned to dive — at least when I got around to getting formally certified — training involved three months. Indeed, for 12 solid weeks I had to spend three hours on Sunday mornings in the pool and three hours Wednesday evenings in a classroom. That’s 72 hours, and that’s before I went anywhere near open water.
While the classroom was a challenge, it paled in comparison with the pool training. First, anyone in the class who could not swim a quarter mile without stopping, and swim the length of the pool underwater on one breath, was told to leave. Then it took three weeks of intensive “skin diving” training before we even saw our first scuba tank. Not that tanks were any relief from the sadistic training ritual. For example, our scuba exercises included ample no-mask drills, and an exercise called “station breathing.” In the latter, one fewer tanks than there were students were first arrayed on the pool bottom. Then, wearing only mask and fins, we had to swim from tank to tank giving up the air supply once it was approached by another diver. The culminating pool training exercise was a session beloved by my instructor and his staff called, threateningly enough, “harassment.”
Fast-forward 40 years. Today, students are lucky to receive more than a dozen hours of contact time with their instructor. And, in my view, anything that smacks of challenge has been all but eliminated from the curriculum on the assumption that we don’t want to stress student divers unduly with unnecessary or unrealistic knowledge and skills.
The rationale, of course, has been to make diving more fun and accessible to more people. Perhaps it would be simpler just to issue folks a C-card with their birth certificate and be done with it.
Don’t get me wrong. I’m not one of those dinosaurs who think diver training has gone to hell in a handbasket. First and foremost, the data on diving accidents just doesn’t support this conclusion. As measured by fatalities, diving is demonstrably safer today than when I started.
So what’s the problem?
The problem is that it appears that we haven’t achieved our goal of getting more people into the sport, at least nowhere near the number we had hoped (especially young people). Yet, given that this campaign to make learning to dive easier has been going on for 30 years without success, you’d think we’d start looking elsewhere for a solution.
Now, as a disclaimer, I have to admit that as someone once responsible for the educational programming of the world’s largest diver training program,
Recently I saw an ad from a dive center proudly announcing, “Learn to Dive in only three days!” It’s not that big of a deal, given that many dive centers have for years been offering programs to train divers in as little as four days (normally over two weekends). But it got me thinking about how much diving has changed over the years, and whether it’s all been for the good.
To provide some perspective, when I learned to dive — at least when I got around to getting formally certified — training involved three months. Indeed, for 12 solid weeks I had to spend three hours on Sunday mornings in the pool and three hours Wednesday evenings in a classroom. That’s 72 hours, and that’s before I went anywhere near open water.
While the classroom was a challenge, it paled in comparison with the pool training. First, anyone in the class who could not swim a quarter mile without stopping, and swim the length of the pool underwater on one breath, was told to leave. Then it took three weeks of intensive “skin diving” training before we even saw our first scuba tank. Not that tanks were any relief from the sadistic training ritual. For example, our scuba exercises included ample no-mask drills, and an exercise called “station breathing.” In the latter, one fewer tanks than there were students were first arrayed on the pool bottom. Then, wearing only mask and fins, we had to swim from tank to tank giving up the air supply once it was approached by another diver. The culminating pool training exercise was a session beloved by my instructor and his staff called, threateningly enough, “harassment.”
Fast-forward 40 years. Today, students are lucky to receive more than a dozen hours of contact time with their instructor. And, in my view, anything that smacks of challenge has been all but eliminated from the curriculum on the assumption that we don’t want to stress student divers unduly with unnecessary or unrealistic knowledge and skills.
The rationale, of course, has been to make diving more fun and accessible to more people. Perhaps it would be simpler just to issue folks a C-card with their birth certificate and be done with it.
Don’t get me wrong. I’m not one of those dinosaurs who think diver training has gone to hell in a handbasket. First and foremost, the data on diving accidents just doesn’t support this conclusion. As measured by fatalities, diving is demonstrably safer today than when I started.
So what’s the problem?
The problem is that it appears that we haven’t achieved our goal of getting more people into the sport, at least nowhere near the number we had hoped (especially young people). Yet, given that this campaign to make learning to dive easier has been going on for 30 years without success, you’d think we’d start looking elsewhere for a solution.
Now, as a disclaimer, I have to admit that as someone once responsible for the educational programming of the world’s largest diver training program,
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