"Pressure's up!" Franklin called.
"Okay. Leave the hatch ajar so it won't lock, and crack the intake valves. Read it again."
"Got a mask for me?"
Norris laughed. "If you're scared, there's one on the shelf. But just open the hatch, take a reading, and close it. There's no danger."
Franklin frowned at him and cracked the intakes. Norris quietly closed the main valve again.
"Drops to zero!" Franklin called.
"Leave it open, then. Smell anything?"
"No. I'm turning it off, Norris." He twisted the intakes.
Simultaneously, Norris opened the main line.
"Pressure's up again!"