Before each dive, the dive guides will tell you everything you need to know about the dive site, currents, the underwater life and how to make the dive. They also indicate any dangers and tell you how and where you can get out of the water. It is mandatory for everyone who dives to attend the briefing and the moment of the briefing is often announced with the ship’s bell. If you don’t join the next dive, tell your guide before the briefing so they don’t wait for you. To prevent any unnecessary waiting, it is nice if everyone comes immediately as soon as the bell is rung. This way you don’t leave anyone waiting.
Before the briefing starts you should check your tank. That means you check the pressure and the gas mixture (if you dive with Nitrox or another special gas mixture) and fill in the Nitrox log. The reason this is done before the briefing is that the crew has some extra time to solve any problem if necessary, while not delaying the dive.