Safety and Security Terms, Defined

The jargon security professionals use can be confusing, but don’t let that discourage you from making informed decisions about protecting your church. The following explanations will help you understand common security terms.

Deadbolt Locks

Single and double cylinder deadbolts are the most common types of locks.

Single cylinder deadbolt locks are operated by a key on one side and a twist knob on the other. They’re easy to use, but their security can be compromised if used near a window. A burglar can break the window, reach in, and unlock the door by twisting the knob. This makes it easy to get in and carry your belongings out.

Double cylinder deadbolt locks require the use of a key on both the interior and exterior sides. If there are windows near the door, this type of lock will prevent a burglar from reaching through and unlocking the door.

Note: For most church or ministry buildings, deadbolt locks may only be allowed on interior or office doors. Fire codes require most buildings that will be occupied by the public to have exit doors with panic bars to allow easy escape in an emergency situation. Check your local fire codes and building ordinances to be sure your exterior doors have the proper locking mechanisms.

Fire Extinguishers

Fire extinguishers are classified according to the types of fires they are best suited to fight. There are three common classes of fire extinguishers:

Class A: Ordinary combustibles like wood, paper, and trash.

Class B: Flammable liquids like grease, oil, and gasoline.

Class C: Electrical equipment like appliances, electric motors, and fuse boxes.

Multi-purpose: The most versatile extinguishers are multi-purpose dry chemical and are classified with an A-B-C designation. They can be used to put out most fires.

Either carbon dioxide units or fire extinguishers with a minimum rating of 40BC are recommended for kitchen areas. Whatever type of extinguisher you use, choose one with a rating of at least 2A and 20BC. Never use type A extinguishers for fires involving flammable liquids or electrical equipment.

Alarm Systems

Monitored alarm systems are monitored by private security companies in another location. The alarm equipment at the protected building is connected directly to a monitoring company. Whenever an alarm goes off, the monitoring company receives an alert and then notifies the proper local authorities and predetermined contact people. There is usually a monthly monitoring fee for this type of service.

  • Passive monitoring. The security company monitoring the alarm system will only be notified if the alarm is set off.
  • Active monitoring. The security company receives a variety of signals from the monitored building, not just alarms. For example, active monitoring would allow the monitoring company to know whether or not the alarm is turned on at a given time or which zones are active.
  • Non-monitored (local) alarm systems alert only the people in the building of an alarm. There’s usually no monthly fee connected with this type of system, but a non-monitored alarm may go unnoticed if no one is nearby.

Fire Detection Devices

Detecting a fire early can save lives and reduce the damage to your property. Heat and smoke detectors are the most common ways of detecting fire.

Smoke detectors detect the smoke produced by a fire. Smoke detectors can be set off very quickly by even a small amount of smoke. However, they can be a nuisance in kitchen areas, where cooking can cause frequent false alarms.

  • Ionization. This type of detector monitors the electrically charged particles (ions) that comprise smoke. When smoke enters these types of detectors, the electrical balance in the sensing chamber is altered, setting off the alarm. This type of detector usually responds more quickly to the small smoke particles associated with hot, fast-burning fires.
  • Photoelectric. This kind of detector uses a beam of light to detect the presence of smoke in its sensing chamber. When smoke enters the chamber, the light beam is interrupted, setting off the alarm. Photoelectric detectors respond more quickly to the larger smoke particles created by smoldering fires.

The type of smoke detector you use is less important than having enough of them and keeping them well maintained.

Heat detectors require a certain temperature to set them off. They are most valuable in kitchen areas and attics, where smoke detectors are not generally recommended. Heat detectors should never be used as a replacement for smoke detectors; a combination of the two can be used for the most effective fire detection.

  • Fixed Temperature. This type of heat detector is activated once the temperature near it reaches a predetermined level. Fixed temperature heat detectors are best for areas that experience frequent, often rapid, changes in temperature.
  • Rate of Rise. This type of detector responds to change in air temperature over a period of time. Rate of rise heat detectors work best in areas that are usually already hot, like boiler rooms.

Burglary Detection Devices

  • Motion sensor devices usually detect infrared body heat moving through an area. When an intruder enters a room, the device detects a new source of infrared energy and the alarm is set off. Some newer technologies also use microwaves to detect motion in a protected area.
  • Magnetic contacts are usually used on doors and windows. One sensor is placed on the door or window itself, and the other is placed on the door or window frame. When a door or window is opened, the magnetic field between the sensors is broken, activating the alarm.
  • Photoelectric beam devices are made up of two sensors, one that emits a beam of light and another that receives it. If something passes through the beam, the alarm is triggered.

Other Security Terms

Glass Breakage Detector. This type of device is activated by the unique sound frequency of breaking glass.


Zones are specific protected areas of a building or groups of detection devices. On many security systems, separate zones can be activated individually, allowing some zones to be active while others are bypassed. Many security system keypads also display which zones are active or in which zone an alarm occurred.

Supervised Lines

Supervised telephone or electrical lines are designed to alert a monitoring company if someone tampers with them. This prevents burglars from eluding detection by cutting phone or electrical lines to disable an alarm system.