Lot's people will say the inflation mechanism or that it looks cool but I'm afraid their all mistaken.
When selecting a BCD you'll check out the sizing options for both your height and your weight. The BCD's primary function is to make sure you float and then secure all of the equipment.
If the number one rule of SCUBA diving is to always breathe and never hold your breath. Rule number two is always be positively buoyant at the surface!
Cylinder marking can vary from place to place but this one is pretty global.
The first number denotes the month it was inspected, the second mark will be different every you see it as it is the testers stamp. The last number is the year it was tested.
Check local laws and regulations to see when scuba cylinders must be hydrostatically tested as it varies from country to country.
Back to basics here and the Air Sharing drill every covered during their Open Water Diver Course and Rescue Diver Course.
Do you remember what to do in the unlikely event of an out of air situation?
This skill is covered at a leadership level in our PADI Divemaster course.
This is something that may vary between agencies and whether it is performed by laypersons or in a clinical environment but some while back simplified the process for all Emergency First Responders.
The ratios are now exactly the same for infant to adult patients and single or multiple responders.
Message me to learn more about upcoming Emergency First Response Instructor courses.