From Pathfinder #195: Heavy is the Crown, which isn't enabled.

Caustic Gas Trap

HAZARD 9

Stealth +20 (master)

Description Pressure plates in the hall trigger the release of caustic gas.

Disable DC 28 Crafting (master) to neutralize the acid or DC 30 Thievery (master) to disable the pressure plates

Collapse

Trigger A creature in contact with the ground travels down this hall

Effect Caustic gas fills the hall, dealing 4d10+26 acid damage to all creatures in area D5 (DC 32 basic Reflex save).

Reset A 10-minute Interact activity and a new supply of caustic gas.

Pathfinder #195: Heavy is the CrownOGL