Abstract: At approximately 10:00 a.m. on March 15, 2017, Employee #1, diver and owner, was inside a 65 foot high water tank with a level of 57 foot of water. He was cleaning the bottom of the tank with a vacuum. He finished and was inspecting the bottom of the tank when he reported to a coworker, ground person, that he was not getting air to his helmet. The coworker turned on the back up air which runs through the main hose. Employee #1 was still not getting air and did not use his bailout tank he was carrying as an emergency source of air. There were no rescue procedures in place to hoist an injured and or unconscious diver from the water. Employee #1 died. unconscious to asphyxiation lack of breathing air to divers helmet, back of use of back up emergency air.