The two men, ages 18 and 34, were transported in critical condition. They were in class at the Ocean Corporation Wednesday morning when something went wrong.
The diving tanks at the Ocean Corporation rise a story above the ground, and it's in one of those where two men ran into trouble underwater at about 10am Wednesday.
Witness David Felan said, "Everything went crazy, fire engines came. There were patrol cars lined up all the way down the street."
Felan works across the street and he took cell phone video of first responders loading the men into LifeFlight helicopters. Another co-worker offered assistance.
"He asked if one of the gentlemen was conscious and they said yes one of them was," Felan explained.
The men in the accident are students at the Ocean Corporation, a school that trains commercial divers in non-destructive testing. Tuition, fees, books and supplies run in the neighborhood of $19,000 for a seven and a half month long course. The director of student affairs explained some of the safety gear students in the dive tanks would use.
"Commercial diving, typically you have a helmet on with surface-supplied air, and then you would have, you know, a bail out bottle as well," explained Jeff Brown with the Ocean Corporation.
Brown says they've never had an accident like this in the Ocean Corporation's 40 year history. On Wednesday morning, it was the instructor and other students who raised the alarm that something had gone very wrong.
He said, "They were able to inform us that there was something that was not going as it normally does and so we took the appropriate action."
Houston police say the two men were in the dive tank and the instructor went to go help another student, and then was informed that there was no sign of the two men in the water. That's when the instructor and other students pulled the victims out, began CPR and called 911.
The school offers morning and afternoon class sessions. Afternoon classes were held as normal.