So, you are ready to turn on the air supply. Slowly turn on the air supply, listening carefully for leaks. Open the valve all the way and turn it back half a turn.
Determine the pressure in the cylinder using an underwater pressure gauge. By checking the pressure rating of the tank and comparing it to the underwater manometer you can determine how full your tank is full ..
Check the regulator by quickly pressing the forced-air button. Air should exit freely and should stop flowing when the button is released. The slight hissing from the mouthpiece can be stopped by quickly pressing the forced-air button or closing the mouthpiece opening. If this fails, notify the instructor.
Check the inhalation and exhalation valve and regulator. It should be easy to breathe in. If it is difficult to exhale, the exhalation valve may be stuck, notify your instructor. If the mandatory airway button works correctly, breathe in several times for a final check. Your breathing should be light and smooth.
After assembling and testing the Do not leave it unattended in an upright position while you put on other equipment. Carefully place it with the back side up. It is advisable to place the regulator on the backrest to prevent sand or dirt from getting on it.
During assembling the equipment in the kit.your instructor will be in the vicinity. Do not hesitate to ask him for help if you have any difficulties or questions.