Common Trade Misunderstandings Part 1: Know Your Fire Alarm Lingo!

Like all businesses, fire safety has its own jargon. The National Fire Protection Association (NFPA), defines hundreds of technical terms. Consumers need to know only a few, and among the most important are:


Area of Refuge

An area that is either (1) a story in a building where the building is protected throughout by an approved, supervised automatic sprinkler system and has not less than two accessible rooms or spaces separated from each other by smoke-resisting partitions; or (2) a space located in a path of travel leading to a public way that is protected from the effects of fire, either by means of separation from other spaces in the same building or by virtue of location, thereby permitting a delay in egress travel from any level.


AHJ (Authority Having Jurisdiction)

An organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure.


Central Station (aka Monitoring Station)

A system or group of systems in which the operations of circuits and devices are transmitted automatically to, recorded in, maintained by, and supervised from a listed central station that has competent and experienced servers and operators who, upon receipt of a signal, take such action as required by NFPA 72. Such service is to be controlled and operated by a person, firm, or corporation whose business is the furnishing, maintaining, or monitoring of supervised alarm systems.



The combination of products, packing material, and container that determines commodity classification. This is what determines what types of fire protection system(s) must be present to protect the various types of commodities.



For the purposes of inspection, testing, and maintenance of waterbased fire protection systems, a condition that will or has the potential to adversely impact the performance of a system or portion thereof but does not rise to the level of an impairment.


FCC (Fire Command Center)

The area of a building where the main components of the fire alarm (fire alarm control panel, testing reports, evacuation system control panel, etc) and/or sprinkler system (fire backflow, hydraulic calc plates, etc.) is located.


FDC (Fire Department Connection):

A connection through which the fire department can pump supplemental water into the sprinkler system, standpipe, or other system, furnishing water for fire extinguishment to supplement existing water supplies.


Fire Classes — What’s Burning?

  • Class A — ordinary solid combustibles like wood, cloth, paper, rubber, etc. Use water, dry chemical or gaseous extinguishers.
  • Class B — liquids like petroleum products, oil-based paints, solvents, lacquers, alcohols plus flammable gases. Water may spread these fires! Use dry chem or gaseous.
  • Class C — energized electrical equipment. Water, bad! Dry chem or gaseous, good!
  • Class D — combustible metals like magnesium, titanium, sodium or potassium. Run! (Leave this to the pros.)
  • Class K — cooking appliances and oils or fats. No water! Gaseous or smother it.


Means of Egress

A continuous and unobstructed way of exit travel from any point in the vessel to an area of refuge or embarkation area consisting of three separate and distinct parts: (1) the exit access, (2) the exit, and (3) the exit discharge.



The use of two or more devices or systems designed to ensure that, if the primary system fails, you have a backup ready for instant use. (As the wise man said, “A measured paranoia is a vital survival skill”)



Your location may have several zones — offices, manufacturing, warehousing, retail, etc. — each of which has distinct fire risks and code requirements. In terms of safety, each zone should be monitored by a fire alarm/response system distinct to the needs of that zone. One size never fits all!