Glossary of Terms


Air Horn Jargon for the Air Horn Noob

Air Horn

The many types of air horns include: train horns, truck horns, boat horns, emergency sirens and even police sirens. They are all powered in a similar fashion. Compressed air is channeled into a diaphragm. As the air releases through the horn bell, it resonates creating a loud honk. 

Air System

Air systems are so commonly used that most people don't even realize what it really is. The actual air system consists of an air driven device and one or more air compressors, air valves, pressure switches, air tanks, air lines and fittings. Some examples of an air driven device are truck and train horns, feed sprayers and air pistons.

Air Compressor

Air compressors are necessary for air equipment, like air horns and even air bags, to function properly. They are mechanical devices that reduce air volume to increase pressure by taking in outside air and release the air into an air system. The amount of air compressors in any given system is dependent on the volume air on the reservoir tanks (one compressor per five gallons of air). 

CFM (Cubic Feet per Minute) and PSI (Pounds per Square Inch)

These measurements rate the volume of compressed air being produced at different system pressures. When PSI, or overall air pressure in the system, increases, volume output (CFM) by the compressor decreases. This resistance causes the system to fill up more quickly during low pressure.

Maximum Working Pressure

A compressor's maximum working pressure corresponds to the most PSI it can generate in an air system before damages are incurred. A pressure switch must be used with a compressor. Make sure the switch matches the working pressure of the air compressor.

Air Filter

A filter is used to keep dust and debris out of the intake duct of the air compressor. An air filter helps prevent faster wear-and-tear. When mounting an air filter, make sure it is facing away from tires or nearby sources of vapor, liquid and other forms of debris. Also, an air filter will not function when submerged. Always use an air filter when using an air compressor and make sure to change it regularly.

Air Tank

Air tanks collect the volume of compressed air in the system. An air tank is needed when a horn has higher air consumption than compressed air production. An air tank should be chosen based on the size of consumption by the device. The total volume of all of the tanks is the total volume of the air system.

Maximum Working Pressure

Just like the compressor, the air tank has a maximum working pressure. It should never be exceeded as wear-and-tear can happen faster and it can even harm individuals who work with an over-pressured air tank.

Pressure Switch

Air compressors use a pressure switch to prevent it from working over its maximum working pressure. The switch will power a compressor until a max, or cut-off point, is detected. The air system and compressor must be linked for the pressure switch to measure properly.