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CIRAS - Engineering - Industrial Ventilation - In-depth Information

Industrial Ventilation Commonly Used Terms (Nomenclature)

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Air conditioning
The process of treating air to meet the requirements of a conditioned space by controlling its temperature, humidity, cleanliness, and distribution.

Air - makeup
Outdoor air supplied to replace exhaust air and exfiltration.

Air - ventilation
That portion of supply air that is outdoor air plus any recirculated air that has been treated for the purpose of maintaining acceptable indoor air quality.

Concentration
The quantity of one constituent dispersed in a defined amount of another.

Contaminant
An unwanted airborne constituent that may reduce acceptability of the air.

Dust
An air suspension of particles (aerosol) of any solid material, usually with particle size less than 100 micrometers.

Energy recovery ventilation system
A device or combination of devices applied to provide the outdoor air for ventilation in which energy is transferred between the intake and exhaust airstreams.

Exfiltration
Air leakage outward through cracks and interstices and through ceilings, floors, and walls of a space or building.

Fumes
Airborne particles, usually less than 1 micrometer in size, formed by condensation of vapors, sublimation, distillation, calcinations, or chemical reaction.

Microorganism
A microscopic organism, especially a bacterium, fungus, or a protozoan.

Particulate matter
A state of matter in which solid or liquid substances exist in the form of aggregated molecules or particles.  Airborne particulate matter is typically in the size range of 0.01 to 100 micrometers.

Smoke
The airborne solid and liquid particles and gases that evolve when a material undergoes pyrolysis or combustion.  Note: chemical smoke is excluded from this definition.

Vapor
A substance in gas form, particularly one near equilibrium with its condensed phase, which does not obey the ideal gas laws; in general, any gas below its critical temperature.

Ventilation
The process of supplying and removing air by natural or mechanical means to and from any space.  Such air may or may not be conditioned.