Get Smart With Joe G.

The ABC�s of diving glossary:

May, 2010 notes brought to you

by the letter P:

PADI - Professional Association of Diving Instructors. The world's largest recreational diving membership organization and diver training organization. PADI Members (dive centers, resorts, educational facilities, instructors, assistant instructors and divemasters) teach the vast majority of the world's recreational divers, issuing nearly 946,000 certifications each year. PADI professionals make underwater exploration and adventure accessible to the public while maintaining a high industry standard for dive training, safety and customer service.

Partial Pressure - Describes the pressure exerted by any component gas in a mixture of gases. For example the pressure exerted by oxygen in breathing air.

Patent Foramen Ovale - A hole in the septum (wall) between the right and left atria of the heart.

Pectoral Fins - The pair of fins at the front of the fish, behind its head.

Pericardium - A double-layered membranous sac surrounding the heart and major blood vessels connected to it.

Pharynx - Portion of the airway at the back of the throat, connecting mouth, nasal cavity and larynx.

Platelet - A round or oval disk found in the blood of vertebrate animals that are involved with blood clotting.

Pleura - Membranes surrounding the outer surface of the lungs and the inner surface of the chest wall and the diaphragm.

Pony Bottle - A common term for a secondary gas cylinder carried by divers as a redundant air source.

Prescription - A written order for dispensing drugs signed by a physician.

Primary Assessment - Assessment of the Airway, Breathing and Circulation (pulse) in an ill or injured person; also known as the ABCs.

PSI - An acronym for pounds per square inch. Used to describe the force of pressure acting on a given area. For technical accuracy, psi must be expressed as psig (pounds-force per square inch gauge) or psia (pounds-force per square inch absolute; that is, gauge pressure plus sea level atmospheric pressure, or psig plus approximately 14.7 psi). psig can be further subdivided into psivg (psi vented gauge) and psisg (psi sealed gauge), the difference being that psisg measures the difference in psi between a chamber of air sealed at atmospheric pressure and the pressure at the measuring point, while psivg measures the difference between the measuring point and the local pressure. Sometimes psid (psi difference) is seen; this should always refer to a measurement of the difference between two pressures.

1 psi approximately equals 6.895 kPa

PSIA - An acronym for pounds per square inch absolute. Used to describe the force of pressure acting on a given area.

Pressure - (symbol: p) is a measure of force per unit area. The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N�m^-2 or kg�s^-2�m^-1). Non-SI measures (still in use in some parts of the world) include the pound-force per square inch (PSI) and the bar. In the United States air pressure is still measured in inches of mercury (as in the mercury barometer). Some meteorologists prefer the hectopascal (hPa) for atmospheric air pressure, because it gives the same numbers as the older millibar (mbar). P = F / A where p equals pressure, F equals force, and A equals area. Often F, is taken to be the of the magnitude of the mean vector force normal to the surface of area A upon which it exerts; the "surface" not necessarily being a that of a body, but for example the cross sectional area of a conduit.

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A SAFETY MINUTE

Joe G's May, 2010 Safety Minute

Saltwater Aspiration Syndrome

You've just gotten home from a dive and you're feeling rotten. You ache all over, are so tired you can hardly hold your head up and you have a low grade fever, nausea, headache or shivering. You might even have some shortness of breath and a productive cough. You wonder if you might not have decompression symptoms.

Well, it might not be bronchitis or pneumonia from some creepie-crawlies in your regulator, but most likely salt water in your lungs that's to blame. First described by Dr.Carl Edmonds, this flu-like condition and short-term respiratory distress in divers occurs when even small amounts of micronized saltwater mist is inhaled into the lungs. Although not well-recognized, it's called saltwater aspiration syndrome and it can be avoided by taking several actions.

Prevention

It may be your regulator. Rodale's ScubaLab has tested some 185 models of regulators and has found a wide variation in the dryness of the equipment. They found that in general, all regulators will have a more difficult time staying dry when you are in odd positions (upside down, on your back, etc.) or just after you have replaced the regulator in your mouth, but top performers keep this to a minimum.

Get your regulator serviced on a regular basis. Some regulators breathe wetter due to the non-return exhaust valves not seating as well as they should. Proper maintenance can help prevent this. Rodale's offers this simple test: With no air pressure to the regulator and the first-stage dust cap firmly in place, exhale forcefully through the second stage and then inhale forcefully. You should get no air on the inhale. If your regulator doesn't pass the test, have it serviced before diving.

Keep your reg in your mouth as much as possible. The best way to keep your regulator breathing dry is to keep water out of the second stage. Use your power inflator, not your oral inflator, to minimize the number of times you remove your second stage from your mouth. Enter and exit the water with your reg in your mouth and use your regulator on the surface during rough water conditions. Do not buddy breathe to share air, but use an alternate air source.

Always exhale before you inhale on a regulator. If you are clearing a regulator in the water, take your first breath cautiously. If any water remains in the second stage, tilt your head so the exhaust is at the lowest point, helping to drain the rest of the water out. The best method for clearing a regulator: put the second stage in your mouth, tilt your head so the exhaust is at the lowest point, then exhale while gently pushing the purge button.

Keep your mouth shut. Even if your regulator is working properly, you will inhale a saltwater mist if you do not keep your mouth firmly sealed around the mouthpiece.

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HAPPY BIRTHDAY
to our May Birthday Celebrants!

Douglas_Cole Marjory_Meechan Nancy_Hejde

Adelle_Nicholson Scott_Riddick John_Kansman

Gayl_Canfield Kelsey_Workman Don_Page

Jimmy_Chu Linda_Meyers Bill_Dietz

Steve_Oller Tonia_Lorey Camilo_Romano

Linda_Sandel Eric_Rohde Darrell_Hejde

Fred_Miller

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The Wet Zone

South Florida Divers, Inc.,
Copyright 2010

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Happy Diving
President's Message
MEETING LOCATION
Calendar for May and Beyond	May Meeting Program
A Safety Minute	Meeting Location
Get Smart With Joe	Happy May Birthday
	2010 OverseasTrips