The Lungs - Potential Problems While Diving (Part 2)

As you can recall the part 1 covered the Air gas embolism. This blog will cover the last three: Pneumothoraz, mediastinal Emphysema, and Subcutaneous Emphysema. Along with this a covering of basic first aid procedures.

PNEUMOTHORAX
If the overpresurized lung tears at it surface, the expanding air leaks between the lungs and the pleural lining (chest wall), causing the lung to collapse, either partially or entirely. This collapsed lung is called a pneumothorax.

This is not nearly as life threatening as an AGE because the victim, in most cases, still has a working lung to breathe from. This collapse lung causes severe chest pain, and may cause the victim to cough up blood.

There is another form of this condition called spontaneous pneumothorax. This occurs with out the expansion of the lungs but through a weakness in the lung itself. This causes a sudden tearing and collapse of the lung.

This condition is uncommon, but can be more serious than the standard pneumothorax. especially if it happens underwater. This type can be aggravated on ascent, when the air pressing on the collapsed lung expands, increasing the pressure of the injured lung.

Since spontanous pneumothorax tends to recur, it inhibits further diving till surgery is performed to correct the problem. Since out a physician who specializes in pulmonary dive medicine. CLICK ON THE PICTURE FOR A BETTER VIEW


MEDIASTINAL EMPHYSEMA

Mediastinal means center of the chest.. This is sometimes called pneumomediastinum, is far less serious that air gas embolism and pneumothorax

This condition, air accumulating in the mediastinum presses on the heart and major blood vessels interfering with circulation. A victim may feel faint and short of breath due to impaired circulation. CLICK ON THE PICTURE TO SEE THE AIR BUBBLES IN THE MIDDLE OF THE CHEST.

SUBCUTANEOUS EMPHYSEMA

This occurs frequently with mediastinal emphysema as air seek its way from the mediastinum, and folowing the path of least resistence, into the soft tissues at the base of the neck.

Air accumulates under the skin in this area. This causes the victim to feel a fullness in the neck and to experience a voice change. The skin may crakle if touched. CLICK ON THE PICTURE TO SEE THE AIR RISE TO THE NECK REGION.

FIRST AID

The first aid for both the decompression sickness and lung overexpansion injuries are the same. You can say that the first aid for the Decompression illess injuries are the same. In fact you do not have to determine on site which you are dealing with to start giving aid to the diver.

Give 100% oxygen to the diver

Simply put, breathing 100% O2 accelerates diffusion of nitrogen from the body to slow and reverse bubble growth, and help bubble elimination. Breathing oxygen also raises the blood oxygen levels and maximizes the effectiveness of the blood that does reach the affected areas. Make sure the air ways are clear and treat for CPR if needed. The best first aid is to get them to a medical facility for proper care.


Now to the lung injuries FIRST AID

Three out of the four conditions are not immediately life threatening, the presence of any of these conditions indicates a lung over-expansion injury has occured. The AGE is the most life threatening and therefore when first aid is given, they treat any of these conditions as though they have AGE.

AGE needs immediate compression to diminish the bubbles in the bloodstream and force them into solution. This restores blood flow to the tissues. None of the other conditions require decompression, provided there is no AGE.

Pneumothorax requires surgical removal of the air from between the collapsed lung and the pleural lining, followed by a lung reinflation.

Mediastinum and subcutaneous emphysema will dissipate on their own as the blood slowly reabsorbs the trapped air. Breathing oxygen can speed up the reaborbtion process.

REMEMBER DO NOT HOLD YOUR BREATH WHILE DIVING ON SCUBA.

The Lungs - Potential Problems While Diving (Part 1)

There are 4 types of injuries that can occur to the lungs by holding your breath on ascent.

LUNG EXPANSION INJURIES IN GENERAL

Most body air spaces respond to pressure decrease with neither complications nor voluntary action by the diver. The Lungs respond to this as well, provided the diver breathes continuously to them keep equalized to the declining pressures. If the diver holds their breath or air traps within a section of the lungs, and as pressure declines expanding air will almost always cause an over-expansion injury.

The "GOLDEN RULE" in diving - never hold your breath while on scuba and while underwater. Panic and ignorance have been the causes of divers holding their breath. Nausea, choking and carelessness have also been causes to this as well.

Obstruction in the lungs may also trap air in certain parts and in effect "hold its breath." A chest cold, or respiratory infection can cause mucus accumulation and cause an obstruction. Smoking has also been implicated in these injuries.

Lung injuries can occur from even a small amount of over-pressurization. Research has shown that starting with full lungs, holding ones breath and surfacing can have an injury in as little as a 3 to 4 feet distance.

Rather than the lungs bursting like a balloon, an over-pressurization tears the lungs. The injury does not occur from the tear to the lungs, but from the air escaping and entering the tissues and / or the bloodstream. Lung injuries can result in 1 of 4 ways: Air embolism, Pneumothorax, mediastinal emphysema, and subcutaneous emphysema.

Any lung injury causes pulmonary capillaries and alveoli to rupture, mixing blood and air in the lungs. This results, often times, to the victim coughing up blood.

AIR EMBOLISM (AGE)

This is the most serious type of lung over-pressurization injury. This results was the air enters the blood stream from a rupture of the alveoli into the pulmonary capillaries, causing an air embolism or arterial gas embolism. Click on image for larger view.

An embolism is any foreign object that enters the bloodstream that blocks its flow. An air embolism is the same but now it is an air bubble that blocks the flow of blood. So as you ascend the once small bubbles become larger and larger due to the expanding nature of the ascent. This is a bubble on the arterial side of the circulation.

Air enters the bloodstream in the lungs flows through the pulmonary vein into the heart, to the left side of the heart into the aorta and then the arterial system. This air bubble can lodge almost anywhere in the circulatory system - can cause severe damage by blocking blood flow to the tissue.

The first main branch off the aorta which include the carotids. The carotids supply the majority of blood to the brain. If bubbles travel into the carotids, which is likely, they will go to the brain and cause cerebral air embolism.

The bubbles deny the brain of oxygenated blood, which causes a stroke. The symptoms include dizziness, confusion, shock, personality changes, unconsiouness, and death. Compared to DCS, the effects of cerebral air embolism and other lung injuries tends to be rapid and dramatic. DCS tends to be delayed.

If the bubbles were to miss the carotids and block the coronary arteries, the result would be a heart attack.

Splash Dive Center, Ron Carmichael Owner Expert Cave Diving Instructor Talks About How to Dive the Caves

25 S. Quaker Lane
Alexandria, VA 22314
Phone: (703) 823-7680

Ron spoke on how to dive the caves. He explained the difference between cavern and cave diving. What equipment, prior training, and mental attitude do you need to dive caves was discussed. If you find cave dive is a dive you would like to tray and make, then you need to listen to this episode. After it you will have all the information to make an informed decisions about this exiting sport.

Click on any picture and it will take you to Splash Dive Center for more information. This is well worth the click. He has a fantastic web site filled with lots of information.

Boat Diving - Why Dive From a Boat and other Important Information

In this blog I will try to explain the many aspects of diving from a boat and what it takes to get the Boat Diver PADI certification card.

WHY DIVE FROM A BOAT ?
1. Opportunities to dive in areas that could not otherwise reach.
2. Allows you to seek out calm water
3. Entries and exits are easier than diving from shore. Reduced need for long surface swims, meaning that the boat will drop you off just above where you will begin the dive.
4. Less wear and tear on the dive equipment

BASIC BOAT TERMINOLOGY

BOW - Front end toward the front of the boat. Also forward is used.
STERN - Back end towards the rear of the boat. Terms also used are Astern and aft, meaning after the decks.
STARBOARD - Right side of the boat
PORT - Left side of the boat. If you remember left port and in leaving the harbor many help you remember which is port and starboard.
WINDWARD - To the weather side or the side which the wind is blowing
LEEWARD - The side of the boat that is away from the wind.
AMIDSHIPS - Has two meanings, between the two sides of the boat and also between bow and stern of the boat
HEAD - A boat's toilet/restroom
GALLEY - Boat's kitchen
BRIDGE - A raised platform on the boat where the boat is navigated

TYPES OF BOATS
INFLATABLES
Where divers want fast, stable, portable, and inexpensive way to get to the dive sites. Typically they carry 2 - 4 divers. Like a river raft type with 2 sir filled tubes. These are considered small boats.

HARD HULL DAY BOATS
These boats include runabouts, pontoon types, flat tops, small sailboats, skiffs, and other small to medium open air boats. Can carry a large number of divers and equipment.

CABIN CRUISERS
These have minimum accommodations for extended overnight stays. Can carry 6 - 10 divers. They have multiple decks for sitting and enjoying the water.

LIVE - ABOARDS
Very large category boats that will allow many divers to live on the boat for up to 1 week at a time. Usually these boats require a small number of crew members to run the daily duties. The distance range also increases with this type of boat.

SAFETY / EMERGENCY EQUIPMENT

Part of the responsibities of the boat captain is to explain what and where emergency equipment is located. It is also important for the diver to also know this information. The emergency equipment listed is the usual type that is needed on the boat.

1. LIFE PRESERVERS
2. FIRE EXTINQUISGHERS
3. SOUND SIGNALING DEVICES
4. VISUAL DISTRESS SIGNALS
5. FIRST AID KITS
6. OXYGEN EQUIPMENT
7. MARINE RADIO
8. BILGE PUMP

It is Important for every Diver to know where each if these pieces of equipment are located

What is the Difference Betweem DCS and DCI ?

First we must define what we mean by DCS. There is an overall term called Decompression Illness (DCI) which most divers get confused and call decompression sickness (DCS), the same. No it is not the same. DCI is the over all term that has 2 subjects below it: 1) DCS and 2) Lung Over expansion Injuries.

DCS refers to the conditions caused by inert nitrogen gas coming out of solution within the body. Lung Over expansion Injuries refer to those injuries that are caused by holding your breath on ascent. Today's blog in on DCS.

There are basically 2 types: Type I deal with skin and pain only which would include the sub type a) Cutaneous DCS and b) Joint and limb pain DCS. While Type II covers the more life-threatening which are the c) neurological DCS and d) Pulmonary DCS.

A) CUTANEOUS DECOMPRESSION SICKNESS

Bubbles coming out of solution in skin capillaries can cause this type. They show up as a red rash in patches, usually in the shoulders and upper chest areas. Although this type is not serious in and by itself, it could lead to a more serious problem.

B) JOINT AND LIMB PAIN DECOMPRESSION SICKNESS

This type occurs in about 75% of the DCS cases. Bubbles growing around and inside the tendons, ligaments and related muscles are the immediate cause. They really do not know how it happens. Symptoms may be found in one place on the same limb or bilateral symptoms. This type may be serious because it can lead to a mores serious problem.

C) NEUROLOGICAL DECOMPRESSION SICKNESS

Effects on the nervous system produce some of the more serious cases in DCS. Bubbles in the nervous tissue may block blood flow "backing up" the system and reduce arterial flow in the affected areas. This affects the spinal cord most often often causing numbness and paralysis in the lower legs. It tend creeps upwards to affect from the neck down.

Bubbles can also travel to the brain causing a stroke as they block blood flow. These symptoms are similar to those caused by arterial gas embolism. These symptoms are blurred vision, headaches, confusion, unconsiousness, and death.

D) PULMONARY DECOMPRESSION SICKNESS

This is DCS that manifesting itself in the lung capillaries resulting in the onset of life-threatening symptoms. These are rare. Silent bubbles reach the pulmonary capilaries defusing into the alveoli. In some cases, bubbles accumulate faster than they diffuse and can block and back up blood flow to the lungs. With less blood flowing to the lungs, the left side of the heart gets less blood, causing the heart rate to rise and a drop in blood pressure. With no treatment, the circulatory system may fail.

Pulmonary DCS creates breathing pain, assocaited with a short, irritated cough, The victim often feels air starved. This is commonly given the nickname "the Chokes". Symtoms tend to progress rapidly and may lead to shock.

HOW TO AVOID DECOMPRESSION SICKNESS

1. Divers should be familiar with the proper use of dive tables through education by a professional diving instructor.

2. Divers using a computer should follow all manufactor recommendations. Conservatism is always the rule.

3. Factors thought to predipose divers to DCS should be avoided. (Covered in next Blog and talkcast). If some factors can not be avoided, use computers more conservative.

4. Divers should be familiar with first aid for DCS, and learn proper procedures for obtaining medical treatment.

RULES FOR DIVING IF GO BEYOND THE
NO DECOMPRESSION LIMIT (NDL)

1. LESS than 5 minutes over the NDL decompression time
a. Do a REQUIRED STOP at 15 feet for 8 minutes
b. DO NOT dive again for 6 hours (Considered the wash out period)

2. MORE than 5 minutes over the NDL decompression time
a. DO a REQUIRED STOP at 15 feet for 15 minutes
b. DO NOT DIVE for 24 hours

These are just some of the basic points on what decompression sickness is, how to avoid, and what to do in the water if you exceed the decompression times

Jack's Dive Center Jack LaPenta Owner

One Town Line Road
Plainville, CT 06062
TEL 860/747-3170
FAX 860/747-5007

Diver Jdiames would like to thank Jack LaPente of Jack's Dive Center of Plainville, CT for being my guest on the show.

Jack’s Dive Center, Inc. , has been serving the needs of divers since 1975. We are the oldest and most experienced Master Scuba Training Facility in Connecticut. Jack received the SSI Platinum Pro 5000 award in 1994, the most prestigious award offered by the diving industry, in recognition of his work in the area of dive training, equipment testing, diving experience (over 8000 dives to date), and community service.

Because of our experience in the area of dive equipment, we have been chosen by most all of the top line equipment manufacturers as direct distributors, enabling us to offer our customers the finest life support equipment available, at the lowest possible prices.

Our Diver Training programs are second to none, offering low student to instructor ratios and very personalized attention. We provide all levels of training from beginner to advanced, and beyond.

Please see our TRAINING PAGE for dates.


Dive travel has always been very important to us. Jack was the first person to take divers from New England to the Cayman Islands, over 30 years ago. He has made 76 trips to Grand Cayman alone, and can lead you to his secret dive locations, known only to himself and his group, but not to the local Divemasters, assuring you pristine reefs and mind blowing diving. Our travel itinerary covers the Bahamas, Caribbean, South Pacific, and local waters. We are also a wholesaler for the famous PETER HUGHES DIVING , offering the finest in live-aboard diving experiences.

Please see our TRAVEL PAGES for dates and destinations.

We have 30 YEARS OF EXPERIENCE IN DIVE TRAVEL, NOBODY DOES IT BETTER THAN JACK’S.

Our service department has won the Excellence in Service and Repair Award 3 years in a row at the Diving Equipment Marketing Association annual show. We can handle all your maintenance needs professionally and in a timely manner.

Frequently Asked Questions

If ever you get to CT, you need to visit Jack at his shop. He is well informed on the local diving sites. May even get you to go with him. I sure did, lots of times. Better yet, stop in, take a class, buy some gear, or just talk scuba diving.

Again I want to thank Jack LaPenta of Jack's Dive Center for being my honored guest on Scuba Diving - Learn to Dive Safe Talkcast.

Advanced Open Water Program

The first certification past the basic Open Water Certification a new diver should obtain is the Advanced Open Water certification. If you were to ask 100 dive instructors their answer would be the same, no matter what agency they teach with. This blog entry will begin to talk about what training the PADI Advanced Open water c - card (Certification Card) offers you. We will discuss the options that you have in dives choices, along with a few required dives that every Advanced Diver must obtain. In general terms this blog will discuss the many specialty dives you can choose from. In future lessons we will take a more detailed look at these specialties, but for now we will talk in general terms and give you a basic overview.

The PADI Advanced Open Water Certification consists of a total of 5 dives, each dive being from a single specialty rating. The course can take place over 1 weekend or in 5 separated days, that is of course dependent on the dive shop and instructor. Again, like the Open Water Course and many PADI courses, a knowledge development portion is required. This means that you will get an associated text. Many text packages comes with a video or CD.

As mentioned above there are a few required dives, they are the Underwater Navigation, and Deep Dive. We will discuss why when a detail explanation is give later. That leaves 3 dives to choice. These 3 dives can be of any dive you desire from the list. More on this later. You and your instructor will discuss what 3 non-required dives you will make. You should read the text and do the reviews for these chosen dives and the two required ones. Let's talk about some of these specialities dives.

DEEP DIVE
In the basic open water program your maximun training depth is 60 feet, although most dives any recreational diver make will be under this depth. However, there comes a time when you want to and need to go deeper. Why go deep? One reason for this dive is that when you go on a boat diver trip, many dive sites do go beyond the 60 foot depth. When you present your c-card to the Divemaster, he knows you have been trained beyond the basic depth. Many ship wrecks are deeper and required this advanced training. They will teach you how to descent down a line, how to make a recommended 15 foot safety stop, how changes in pressure affects air consumption and dive time, to name a few points.

UNDERWATER NAVIGATION
Have you ever gotten lost on land ? Think about what it would be like underwater. This one dive will show you how to dive a square, a triangle with a compass. How to look at plants, rocks, wave patterns, and sun shadows to help with navigation. Will you be an expert navigator at this point. No. Thats why you need more training.

BOAT DIVER
Diving on a boat is one of the best ways to dive there is. Boat diving gets you to locations that land diving just can not match. In this dive you will learn how to dive within a very confined and control space. Learn how to exit for the dive and enter once the dive is completed. Learning to boat dive is fun.


Nautilus Explorer ship holds 20 divers and 7 crew. Each 2 divers have separate berth with their own shower and head. She sails from Victoria, Canada. My berth was the third portal from the stearn on the starboard side. See you also learn nautical terms in the boat diver course.


Small skiff taking geared divers to a dive site.


Many boats moored side by side in the Red Sea. There could be as many as 10 boats with 300+ divers in the water at any on time. Surprising thing about is, there is plenty of room under water.


Divermaster helping a returning diver back onto the boat. This is the scene many times after a dive.

WRECK DIVER
In this first dive, they will start to teach you how to navigate around a wreck. when I was studing to teach the wreck course, my course director told us that the first dive brief goes like this, " This wreck underwater on the bottom should be floating on the surface." And after that all else is fluff. There is a little bit more than that, but that really sums it up. In the wreck diving certication, you wil learn some amazing things.


Sapona is made entirely out of concrete. It was once owned by Al Capone for drugs and protitution. Visit SAPONA Site for more information. The S. S. Sapona lies in 17 foot deep water, 4 miles south of Bimini Island in the Bahamas. Military target practice and the weather have stripped the hull of most of its concrete. The wreck is a very popular diving site since it is in such shallow water and attracts a multitude of fish. Check out Blackbeard's Cruises to take you to this wreck, and many other sites including a controlled shark dive.






NIGHT DIVER
If you learn to dive at night properly, it opens up a whole new adventure in diving. You will learn how to use your underwater lighting systems effectively. How to signal underwater when you can not see your buddy, to name but a few. More importantly, during a night dive you will see fish that only come out at night. While in Bonaire diving, we did many night dives. But on one of these dives we a small cleaner shrimp, and the largest lobster you ever did see. So learn to dive at night, it is fun and an exiting part of diving.

PEAK POSITIVE BUOYANCY (PPB)
If you heard by first ten minutes lesion on buoyancy this is a must dive and certification for ALL divers. During these dives you wil learn how to maintain a neutral position in the water. Learn how to adjust your weight to make you move more horizontal than vertical. Learn also how breath control is an important part of any dive.


Learn how to hover motionless in the water column. A very important skill to master and learn.

These additional dives can some from any of the above or from these listed below: Drift diver, altitude diver, dry suit diver, ice diver, multilevel diver, search and recovery diver, underwater naturalist, river diver, underwater videographer, enriched air, dive propulsion vehicle (DPV), and underwater photography. As you can see there a lot of options for you to chose from. I must mention that these dives are introductory dives. They are the first dive you would make in any full specialty certification. Once you make these dives, they can and will be credited to that specialty.

Visit the links on the side for many valuable free stuff.

What is the Open Water Scuba Course ?

Discussion is on what is involved in the basic Open Water Scuba Diver course.

This is the card you will get if you complete the PADI Open Water Scuba Program.

In most classes you will be given a course book.
This book is divided into 5 sections which relate to the 5 pool sessions (if you take the PADI open water training course, which I highly recommend that you do. Depending on the class structure, you will be asked to read the book and do all the exercises before attending class ( a chapter at a time). Some classes maybe during the week, while others could be 2 separate weekends. In any event you will have FUN while learning how to breathe underwater. Just think when you are done, you can go on many trips and see fantastic fish and animals in thier underwater home. In class, the instructor will have you learn all material to 100 % MASTERY. If on the 4 short quizzes and 1 final exam, the student must understand all missed questions. If you missed the question, you will know why you missed it.

Topics in the course book are: how to use equipment and how it works and why, bouyancy - why things float and sink, why knowing about pressures in the water are important, how NOT holding your breathe in diving if the # 1 rule, how to effectively descend and ascend safely, basic underwater hand signals, how to use the standard dive tables, to name but a few.

After the class, each student must master a number of underwater skills. These skills will be done at a local swimming pool, where the environment is safe. Some of these are breathing underwater, swimming without sinking to the bottom, taking off and putting on your mask, how to recover your regulator (mouth piece) if it comes out of your mouth, how to inflate your BCD (Buoyancy Compensation Device) under water, taking on and off the BCD in water, and many more.

When all students master these skills it will be time to advance to a local dive site. The local dive site could be a pond, a small lake , or a sound. Don't worry, there will be plenty of staff there to assist you during this time. Their main goal is for you to have FUN and learn how to safely dive in the Open Water. No new skills to learn, all the skills you did in the open water will be repeated here in open water. There are a total of 4 dives that must be preformed.

When you complete these open water dives you will be awarded and Open Water Scuba Diver card. With this card you can rent dive gear, and air at the local dive shop. Now it is up to you to contact a local dive shop and learn to dive. As you are aware from my Bio, I am a PADI dive instructor and believe that PADI is the best dive organization in the world. Go to this site for PADI. You will not go wrong if you take your class from an approved PADI dive shop . Go to start your dive, and find a local one in your state and city. Tell them how you found them, they will be glad you did. Good luck and I hope to see you "under the water"

The diver on the platform to the left is getting ready to do a Giant Stride Entry. This entry in one that you might use when diving from a boat. Watch out below, here I come.

These two pictures were taken at the Blue Hole in Santa Rosa, NM. This is an open water training site that is used by many dive shops from about 3 states. I have helped conduct many classes in these waters.






These last three pictures are of Dutch Springs in Bethelhem, PA.

Check out my sponsers links...they have a lot of free stuff to give you.

Introduction: Who is Diver James - The Scuba Guy ?

In this coming episode I talked about my dive background. How I started to dive in 1980 while overseas in the NAVY in the Philippines. Then not having dove again till 2001. At that time I got certified with PADI. After my basic open water training, I went crazy. I took every course as a student I could take. In fact I took almost every student dive course PADI has. Then one day in Tigard , OR. I asked what a Divemaster was. The next day I started my professional diving career. I later moved to Albuquerque, NM and got my Assistant Instructor certification. Then I moved to Philadelphia and enrolled to become an Instructor. Again, I went crazy and enrolled to teach as many specialties as I could, Again I moved to Reno, NV and got my certification to help teach instructors.


This BLOG is designed to enlighten divers and potential divers how to dive safely. To give some basic dive instruction. To talk about equipment issues. In this blog I will up date the material to reflect the talkshoe broadcast. If during my talk, a picture is needed, I will try to post it here for viewing.

Factors Predisposing Divers to Decompression Sickness

As mentioned in the last blog and talkcast, the way to avoid is to limit the factors that predispose divers to DCS. Some factors are unavoidable. So make the others of more importance. Physiologists still don't understand all factors that may predispose an individual to DCS, but the list is a start to what they do know. No matter what you do, DIVE CONSERVATIVELY. NEVER DIVE TO THE LIMITS OF A DIVE TABLE OR COMPUTER. They may be wrong for you at that time.

Following is a short list of these factors and a brief explanation.

FAT TISSUE

Fat tissue is slow tissue, holding a high amount of dissolved nitrogen. A lot of fat tissue increases the nitrogen retained in the body. Divers that have a higher fat ratio to lean muscle are more likely to have more nitrogen after a dive and therefore have a slightly higher risk of DCS.

AGE

The circulatory and respiratory system works less efficiently in the older population. This interferes with gas exchange. Remain fit by reducing the fat content and exercising regularly to counter this factor.

DEHYDRATION

Dehydration reduces the quanity (volume) of blood available for gas exchange, slowing nitrogen removal from the body. Comsumption of diuretics (caffine), profuse perspiration, and even the dry scuba air tend to dehydrate the diver. During metabolism of alcohol uses a great deal of water. Thus a diver with a hangover is more likely to be partially dehydrated. To do: Make sure you drink plenty of water before, during and after the dive. More than you normally would do.

INJURIES AND ILLNESS

Any condition that affects normal circulation can potentially affect nitrogen elimination. Healed conditions may reduce local circulation difficulties. Also any illness can produce a general reduction in circulation. Make sure you do not dive if you have any injuries or illnesses. It is simply not worth it. Better to heal and dive a different day.

ALCOHOL

Alcohol consumed before or after a dive alters physiology, we all know that but in favor of DCS. Alcohol tends to accelerate circulation and can cause tissues to carry higher amounts of nitrogen. After a dive, alcohol dilates capillaries, possibly increasing the rate of nitrogen release and bubble formation.

CARBON DIOXIDE

Elevated carbon dioxide from skip breathing or improper breathing may interfere with the gas transport by the circulatory system by dilating the capillaries, and again increasing nitrogen uptake.

COLD WATER

During a cold dive, inadequate exposure protection in moderately warm water, changes normal circulation, as the body trys to stay warm. At start of dive, circulation carries nitrogen to all parts of the body, but as heat is conserved, this reduces circulation to the hands and feet. There is less blood to carry away dissolved nitrogen during ascent.

HEAVY EXERCISE

Exercise while diving increases blood circulation, carrying nitrogen to all parts of the body faster than normal. After resting, circulation returns to normal, and so there is no corresponding circulation to accelerate nitrogen elimination.

ALTITUDE AND FLYING AFTER A DIVE

Reduced atmosphere pressure at altitude increases the pressure gradient between tissue and the ambient pressures and can possibly cause larger bubble formation. Once DCS occurs returning to sea level does not usually correct the problem

Wreck Diver (Part 3) Basic Diving Techniques 2

In the last Blog on Wreck Diving (Part 1), I covered navigation and evaluation, deep wrecks, and mapping techniques. This blog will cover wreck penetration, and special situations.


WRECK PENETRATION

1. Have all necessary equipment
Have at least 2 dive lights per diver--to make sure no one will be without a light inside the wreck. Have a wreck reel and line to provide penetration line marking your way in and out. A slate comes in handy to make interior map as you navigate around. A pony is needed in case of an out of air situation.

2. Observe the limits established for diving in overhead environments
Stay within the natural light zone -- you always have a guide to the outside should the light fails. Limit your penetration to the linear distance of 100 feet. Follow the "Rule of Thirds". Use no more than 1/3 of your air entering. 1/3 for exiting, and 1/3 for reserve. (See www.diverjamesten.com for show on diving to you limits)

3. Before entering the wreck, attach the end of the line to a sturdy piece of the wreck
Put the line through a hole and tie using a secure knot. Consider creating a loop in the line and pass the entire reel through it.

4. After entering, secure the line to another point just inside the wreck
Check the entry for possible hazards. Look to the ceiling and see if your air bubbles are causing too much silt to rain down. If this happens, abort the penetration.

5. Move slowly through the wreck while maintaining neutral buoyancy
Keep light tension on the line as you move through the wreck. Wrap the line around non-sharp objects. Use gentle sculling kicks to avoid silting up the bottom. When pracical, pull yourself along the wreck - do not pull on the penetration line.

6. Use the penetration line as a guide
Swim along with the line just below your chest level, and to one side. Stay close to line to reach out and grasp if at any time. Gently make and "O" around the line with your thumb and fingers.

SPECIAL SITUATIONS

1. Stress
If problem occurs - Stop, Breathe, Think, and Act (see Stress Underwater at www.diverjamesten.com)

2. Silt Out
Stop all activity, and wait a few minutes to see if it calms some. If continues, immediately make loose contact with penetration line. If it does not settle, signal "up" and abort the dive and turn to exit. DO NOT LET GO if the penetration line. Leave the reel in place as you exit- you can retrieve it later, unless you know all divers have exited the wreck.

3. Lost or cut penetration line
If you can not find the line, or cut, stop and look for the natural light from the exit. If necessary, cover your light to help you see (DO NOT TURN IT OFF), and let your eyes adjust. Follow natural light to exit, using the map as a guide.

4. Light failure
Go to your backup light. If this is your only back up, you should abort the dive and exit the wreck. Do not dive with only one working light.

5. Air supply loss
If air is low, switch to your pony bottle, and exit the wreck immediately. If you have no pony, secure your buddy's alternate air source and exit the wreck with the donor leading.

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Wreck Diver (Part 2) Basic Diving Techniques I

As a wreck diver there are many different techniques that you must consider. An attempt will be made here to bring out what would be consider basic techniques. They could be divided in the following sections. Keep in mind that what is written here is just the basics and a highlight of these techniques.

NAVIGATION AND EVALUATION

1. Follow the wreck's layout
Use natural lines to navigate, ie swim along the hull or along one side. Go up one side and back the other. If the wreck is fragmented, pick some prominent points and swim in a relative track. On occasion, look back to see what the return trip will look like.

A FANTASTIC underwater
photo of the
HILMA HOOKER.
A must see.


2. Establish a baseline for widely scattered wrecks
Use a compass heading and swim in that direction, being carefull to note that some compasses may not work if close to the metal hull of the ship. In low visibily or current, use you wreck reel tied off to a point as a return line to your starting point.


3. Evaluate the wreck for possible hazzards and stability
How is the wreck sitting ? Does it look stabile ? Look for sharp objects and entaglements. Check to see if walls and structure appear stong and intact. If considering to penetrate this wreck, check for possible entry ways that are free from hazards.

Click on the photos for more pictures about the Hilma Hooker.

DEEP WRECKS

1. Be a trained PADI Deep Diver.

2. Have proper deep diving equipment available
Hang a tank at 15 feet to assure ample air for a saftey stop. Set a reference line for orientation for descents and ascents. Have a first aid kit available.

3. Take the effect of nitrogen narcosis into account
Plan the dive to keep objectives at or below 100 feet. Avoid changing your dive plan on deep wreck dives. Stay close to your ascent point so if you need to come up you know where it is.

MAPPING

1. Use a large slate to draw more accurate details.
Note distances, angle, directions, depths, points fo interest. Try to make true to scale. The more accurate the better.

The Emerald

This is a sample of a wreck map. This is The Emerald wreck. See article here by the New Jersey Scuba Diver for more maps and history of this wreck.

2. Compass use
Use compass and navigational aids to determine angles between prominent points of the wreck.

3. Distance determination
Use kick cycles and arm spans to estimate size and distance. For more accurate measuraments, use a marked rope or measuring tape. (See the above link for a map grid of this wreck...this is a good site to study wrecks, esp on the east coast.)

Wreck Diver (Part 1) Ways to Protect the Aquatic Realm and Equipment List

Lets start off first by listing ten ways the wreck diver can protect the aquatic realm.

1. Dive carefully on wrecks, especially in fragile aquatic ecosystems.
2. Be Aware of your body and equipment placement when wreck diving.
3. Keep the wreck diving skills sharp with continuing education.
4. Consider your effect on aquatic life through your interactions.
5. Understand and respect underwater creatures who have made wrecks their home.
6. Resist the urge to collect souvenirs while wreck diving. Wreck artifacts and debris may be protected by law, but are also the home of the attached or shy aquatic life.
7. If you hunt and/or gather game while wreck diving, obey all local fish and game laws.
8. Report environmental disturbances or destruction of your dive sites.
9. Be a role model for other wreck divers when interacting with the aquatic environment.
10. Get involved in local environmental activities and issues.



STANDARD EQUIPMENT

**Exposure Suit
Wrecks often have sharp, rough edges. Your suit should be thick enough to help prevent cuts or abrasions. On deeper dives the temperature will be colder, your suit should also be based on the bottom temperature of the dive, not what the temp of the surface is.

**Gloves
Gloves will not only protect your hands, but wearing sturdy gloves can be used to help pull you along a wreck.

**Knives / Dive Scissors
Wrecks often have monofilament lines or fishing nets on them. You need a way to cut free if you get entangled. Carry a knife that is easily accessible. Carry the scissors in the holder at about chest level. Consider carrying 2 knives and a pair of scissors, making sure you put them in different locations.

**Dive Lights
Ambient light may be dim in and around a wreck. Carry a dive light to look in the crack and crevices. If penetrating a wreck, carry a primary light and at least 1 additional light per diver. More backup lights the better. Before the dive, ensure that all batteries are changed and the lights are in working order. Check the O-rings and make sure that the light is well closed and sealed.

**Slates
Slates are used for mapping the wreck as well as communication. Consider carrying a grid slate for mapping and a smaller one for communication.

**Clips
The extra equipment you carry on a wreck dive makes clips useful. Choose clips that are sturdy and easy to use underwater. Consider putting clips on the BCD.

SPECIAL EQUIPMENT

**Penetration Lines and wreck reels

Only make penetration dives with proper lines and reel for visual / tactil reference.
The lines should be strong, durable, and made from a non-biodegradeble material -- nylon is best. The reel should have 3 times the lenght as you would need and easy to operate. Inspect lines and reels BEFORE each dive.

**Pony Bottles
Having a complete independent air source in addition to the standard alternate air source is highly recommended. Maintain a pony bottle with a separate attached regulator. Pony bottles come in a variety of sizes as shown below. The size you need is how much extra air you want to carry and of course, your physical size as well.

Check bottles that it is filled and system is operating with no flaws. Attach pony bottles with a special harness and put 2nd stage in a place that can be easily accessed.



This is only one type of band attachments for the pony bottles. Click on above picture to go to products page.

READY, SET, GO ...
Evaluate your readiness for wreck diving.

1. Get familiar with local laws concerning wrecks. Know what you can and can't do on the dive. The local dive shop should help you with this.

2. Develop a dive objective for exploring the wreck. Determine what you want to see and do the dive depending on it's size.

3. Get familiar with the wreck's position underwater so you can formulate a navigation plan.

4. Determine your physical and emotional readiness. Be ready to dive. Are you trained to dive on this wreck, and at this depth. If not, take a guide with you.

5. Check your Recreational Dive Planner - confirm No Decompression time.

6. Use familiar Equipment. Do not dive with new equipment till first you made a dive that was not so chalenging.