312 / | HD | SUPPORTS: CABINET STRUCTURE |
31 | DF | WITH GAS OR VAPOR TREATMENT OF MATERIAL {3} |
31.01 | DF | .~ By wetted surface exposed to material chamber and continuously contacted by unconfined gas {2} |
31.03 | DF | .~.~ Moistened chamber wall {2} |
31.05 | .~.~.~ Of porous fabric sheet only {1} | |
31.06 | DF | .~.~.~.~> Liquid down flow with bottom gutter |