In water: the excess of hydrogen ions (H+) over hydroxide ions (OH-) that occurs where the pH is less than 7.

A form of aluminium oxide that absorbs moisture readily and is used as a drying agent.

The quantity of air delivered, expressed in cubic meter per minute at the conditions of temperature and pressure existing at the inlet to the compressor.

An angle that is greater than 0 degrees but less than 90 degrees.

Angles that share a common vertex and a common line.

A substance containing enormous internal surface area that is capable of extracting one or more constituents from a mixture of gases or liquids by the physical attraction of the extracted material to the above mentioned surface area. No physical or chemical change of the adsorbent results.

The binding of atoms, molecules or ions to the surface of a liquid or solid. This is different than Absorption which is bringing the atoms, molecules or ions inside the solid or liquid . The binding to the surface is usually weak and reversible.

Alberta Fire Code.

Devices that remove the heat of compression of air or other vapour after the last compression stage.

The growing or coming together of small, scattered particles into larger flocs, or particles, which settle rapidly. Refer to Floc.

The simultaneous control of the physical and the chemical conditions of the atmosphere within a structure. This is achieved by affecting some or all of the following air conditions: temperature, humidity, motion, distribution, pressure, dust, bacteria, odours, toxic gases, and ionization.

A condenser cooled by the natural or forced circulation of air through or over it.

A device, usually at the ceiling, used for the distribution of the conditioned air from the terminal of the air duct(s).

In an electrical machine, the space between the rotor and stator across which magnetic lines of flux must travel through air.

A heat exchanger that supplies heated air for combustion. Heat is transferred from the hot flue gases to the combustion air.