He checked various connections, then flicked a switch and opened the gas valve.

A sensor detects when the glow bar is hot enough and opens the gas valve.

These will enable the pilot to shut off a gas valve in the case of a leak even if there is a flame present.

An axial catwalk was added across the center of the ship to provide access to the gas valves.

There are two common types of gas valves.

However, they did not turn the main gas valve on and that part of their plan failed.

"Bring us to 1500 meters," Buch told the man controlling the gas valves.

The only control he had now was the gas valve.

There must have been a gas valve in the janitor's room that he hadn't seen.

He found the gas valve and turned it off.