(under subclass 69) Subject matter comprising a means for admitting air to the ventilated space and a separate means for exhausting air from the space.
(1) Note. The air admitting and exhausting means must be separate and distinct from one another. A single means which admits air to the space under one condition and exhausts air from the space under another condition is not included in this and indented subclasses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
8+, for a chimney or stack having both inlet and outlet airways.
100+, for an apparatus for positively moving air present in a ventilated space in a transporting device from one position to another within the space without adding fresh air (i.e., recirculation alone).
103+, for railcars, buses, or trailers having both inlet and outlet airways.
145, for a means combined with a closure which acts alternatively to admit air to and exhaust air from a ventilated space.
237+, for static structures (e.g., buildings) having both inlet and outlet airways.
