(under subclass 237) Apparatus including means responsive to air conditions either in or outside of an enclosure or the air condition in the supply system for the enclosure to maintain a predetermined pressure in said enclosure and/or a difference in pressure between said enclosure and the outside atmosphere.
(1) Note. Systems which maintain enclosures under air pressure but having no air condition responsive automatic controls are in other appropriate subclasses of this class, e.g., those having differential air input and discharge.
SEE OR SEARCH THIS CLASS, SUBCLASS:
70, for pressure regulation with a vehicle and note the classes referred to under "SEARCH CLASS" for that subclass.
255, for pressure regulation of a structure which includes an inlet airway.
340, for pressure regulation of a structure which includes an outlet airway.