Scuba

Believe it or not, there are several alternatives. In a wet suit ... just do it. If you are in a dry suit, then you can wear adult diapers ... or if you are a male, you can add a "p-valve" which utilizes an external catheter (i.e. condom type) that attaches to a tube that is attached to the drysuit so a male diver can relieve himself outside the drysuit now.

its helium

Boyle's Law.

"Squeezes" are caused by the effects of pressure on trapped air spaces.

It depends on the course in question.

Let's say you are with PADI, who I do my diving with...

For the original Open Water Course, you usually have two days in which you have the lessons from your instructor and your confined dives.

However, there is a book that they expect you to read, make notes, and do the quizzes, and the summary. I am warning you, they are rather long. If you have to work, or do school and homework on top of it, leave yourself 2-3 weeks beforehand, just so you can go through it slowly, and carefully.

There is a test at the end of it, in which you must get 75% in it to pass. you can always take it again, that same day, but what is the point.

Then you need 4 open water dives to do afterwards.

The advanced open water has less theory, but more practical

This is the same with the Rescue Diver Course, and the major ones.

You also have the speciality courses.

Some of these require both theory and practical and a theory test.

Some require theory, practical, and then a practical test.

Some require theory and theory test.

the speciality courses all have theory booklets that you must read and complete, however, this is only around 60 pages, nothing like the open water

So it really depends I'm afraid

There are many reasons for stopping a dive. If you're running low on air, dangerous water conditions, cramps are also common on dives as well as the bends.

Well... drowning is a danger of water sports...

H

I believe the original UDT's werwe brown gum rubber. When they changed to the more durable rubber they were in black. Good to see them back on the market. --- The original Voit prototypes were indeed gum rubber. But when the Navy contracted Voit, they released the "UDT" fin, per milspec in black, although they kept the molds and continued the gum rubber process. The more recent rerelease is probably more nostalgia than anything else -- when swim fins were first developed, rubber was an excellent choice of material. Nowadays, rubber is way too pricey, too heavy and not durable enough. SpecOps groups seem to be using the US Divers Rocket Fin -- a none-to-modern plastic composite.

The qustion should be rephrased to "What is the DENSITY of air at 15 psi." Volume is independent of mass, i.e. one cubic foot is one cubic foot regardless of pressure. Density refers to how much mass there is per unit volume. At 15 psi or, more accurately 14.7 psi, (atmospheric pressure at sea level) the density of air is 0.0805 pounds per cubic foot (pcf). Not much. This is commonly called one "atmosphere." Compare that with 62.4 pcf for fresh water and about 64 pcf for sea water. I ran some quick numbers and found that for each 33 feet of sea water depth the pressure increases by one atmosphere (14.7 psi.) The common recreational dive depth limit of 60 feet corresponds to just under 3 atmospheres, including 27 psi water pressure plus 14.7 air pressure above the water for a total of about 42 psi.

Yes, but any bit of force in any horizontal direction is always exactly cancelled by

an equal-size bit of force in the opposite horizontal direction, so there's never a

NET horizontal buoyant force. It's only apparent in the upward vertical direction.

taking the normal density of water as 1g/cc, the amount of water in 1 cubic inch would be 16.387064 grams.

Addition about 1 cubic inch.

This order is the regular certification, the Advanced Diving certification, and the Rescue Diving certification.

The purpose of a depth gauge is to measure the depth of water. It is used by scuba divers to make sure they don't go too deep because the deeper they go the more pressure the water is.

Yes, scuba cylinders can be cleaned and they are if they are going to be used with oxygen enriched air (i.e. nitrox). There is a debate whether they need to be cleaned if used for "low" oxygen nitrox if the nitrox is premixed.

Going higher in altitude has less air pressure at high altitude. Less pressure = bigger bubbles. Bigger bubbles = the bends and can lead to bursting alveoli in the lungs which leads to a visit to a recompression chamber.

because it is convienent to check it is like wearing a watch it is very easy to see.

There are a few reasons why a new tattoo looks dull. It could be bad quality or that the person did not take care of it correctly.

Balsa

divers bends is when two gay people have sex the the blood pressure rises and their dicks burst

PV=nRT

Helium

Deep sea divers wear special suits to keep their body from getting too cold. They also wear these suits to keep from being crushed under the pressure.

Yes they do. It is done to prevent snow blindness. Sunlight reflecting from snow and ice can be very bright and can cause "snow blindness" so climbers often wear dark googles to filter this bright light.

Diving with sinus congestion can be extremely harmful. As you descend, you must "equalize" your ears otherwise a "squeeze" occurs. This "squeeze," as divers call it, happens when there is an air pocket of lower pressure in the sinus cavity or by the ears and higher pressure around it. It causes extreme pain and may rupture an ear drum, if you try to get through it. PADI - the diving certification organization - advises strongly against diving with sinus trouble, even if controlled by decongestants.