Corrosive acids deals 1d6 points of damage per round of exposure except in the case of total immersion (such as into a vat of acid), which deals 10d6 points of damage per round. An attack with acid, such as from a hurled vial or a monster’s spittle, counts as a round of exposure.
The fumes from most acids are inhaled poisons. Those who come close enough to a large body of acid to dunk a creature in it must make a DC 13 Fortitude save or take 1 point of Constitution damage. All such characters must make a second save 1 minute later or take another 1d4 points of Constitution damage.
Creatures immune to acid’s caustic properties might still drown in it if they are totally immersed (see Drowning).