Fire Protection Terms and Definitions

Active fire protection systems include automatic features to protect a building and its occupants from fire. It uses moving mechanical or electrical parts to achieve the fire protection goal. Active fire protection systems attempt to contain the spread of the fire by dispersing water or other compounds.

A low air alarm is a condition in a dry pipe sprinkler system in which the air pressure has fallen below a pre-set level. This is utilized to warn the building’s occupants that the system’s air compressor may be compromised (or the power to the unit may be turned off) and a further reduction in pressure may cause the system to trip.

Passive fire protection systems contain fires without taking action by utilizing four different methods: structural fire protection, compartmentation, opening protection, and firestopping materials. Passive fire protection gives people time to escape from a building that has a fire.

The time, in minutes or hours, that materials have withstood a fire exposure as established in accordance with an approved test procedure appropriate for the structure, building material, or component under consideration.

A fire compartment is a space within a building that is enclosed by fire barriers on all sides, including the top and bottom.

A fire damper is a device, installed in an air-distribution system, that is designed to close automatically upon detection of heat to interrupt migratory airflow and to restrict the passage of flame.

Standpipes are similar to automatic fire sprinklers and built into the initial construction of a building. They are installed in the stairways of buildings that exceed a certain height or size, but can sometimes be located throughout the walls of the structure. Standpipes provide water flow to hose valves, which can be used by firefighters to connect fire hoses. Much like fire hydrants, firefighters can utilize this connection to spray water from the building’s main water source.

A dry pipe fire sprinkler system is a type of sprinkler system that uses compressed air or nitrogen to charge the sprinkler lines, keeping the system “dry.” A broken head vents air, lowering the pressure and opening a valve to allow water to flow. They are often used in areas where sprinkler lines could freeze, such as large freezers or outdoor covered docks.

A type of fire suppression sprinkler head used in high-risk environments, designed to break at a lower temperature and flow at a higher rate than a typical sprinkler head.

Absorbed glass mat is a type of sealed lead acid battery where the electrolyte is immobilized in fiberglass or polymeric fiber separators. AGM batteries are rechargeable, less expensive than their lithium counterparts, and are capable of deep-cycle operation. They are, however, significantly less energy dense and do not maintain their voltage as they are depleted.