There are 14 tissue compartments used in the decompression model for the PADI RDP and each has 6 halftimes before it is considered saturated.

If it is a 60-minute halftime this means it will take 60 minutes to become 50% full, 120 minutes to 75%, 180 minutes to 87.5%, 240 minutes to 93.8%, 300 minutes to 96.9% and 360 minutes to 98.4% where it is considered to be saturated.         

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Platelets clump together to form clots. Without a sufficient amount, clotting isn't possible and even minor bleeds can be dangerous.

Low platelet count or Thrombocytopenia can be caused by many different disorders and you should consult a doctor if you show any signs or symptoms.

As stated in the general standards section of the PADI Instructor Manual, all PADI course are performance based rather than time based. 

This means that each student must reach an understanding of all academic sections and pass any quizzes or exams linked to the PADI programs they are being trained in. It also means they must reach PADI's definition of Mastery - reasonable comfortable, fluid and repeatable for a diver of that certification level - in the course objectives and performance requirements. 

I'm sure this one caught a few people out as it is in both freshwater and at altitude while asking for partial pressure. Let's break it down piece by piece.

Firstly let's work out the gauge pressure for 22m/fw - 22x0.097= 2.134ATM

Now let's add on the barometric pressure at the current altitude - 0.8+2.134+2.934ATA

Lastly, we can multiply the ppO2 by the ambient pressure to get the answer to our question - 0.21x2.934=0.616ppO2

Have any more question concerning physics in diving, feel free to message me and I'll see how I can help.

Home to more than 25% of all marine life while only covering 1% of the ocean floor, coral reefs are both protectors and providers and are the most diverse ecosystem on our planet.

We must do everything we can to protect them.