an instrumentality invented for a particular purpose

a filter that removes dust from the air that passes through it

a mechanical system in a building that provides fresh air

expose to cool or cold air so as to cool or freshen

furnish with an opening to allow air to circulate or gas to escape

expose to the circulation of fresh air so as to retard spoilage

a type of local ventilation device that is designed to limit exposure to hazardous or toxic fumes, vapors or dusts.

a very small opening in a window or other building envelope component to allow small amounts of ventilation in spaces intended to be naturally ventilated when major elements of the design - windows, doors, etc., are otherwise closed.

a filter that removes dust from the air that passes through it

a mechanical system in a building that provides fresh air