| 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 |