Guideline 16.2: The appropriate security hardware is utilized
When should security hardware be utilized?
While security staffing and controlled access to an exhibit are primary security strategies, mechanical deterrents and monitoring devices provide additional security. And since it can be impractical for some institutions to provide sufficient staffing, a well-designed exhibit incorporating security hardware will form the first line of defense.
The particular security features built into an exhibit should be tailored to the circumstances of the exhibit space, the nature of the exhibit objects, and the staffing available. More sophisticated protection measures will be required for exhibits with a higher risk of theft or vandalism. A security risk assessment will establish the level of risk for a particular exhibit. [For more information on security risk assessments, see Guideline*.]
Factors to consider:
- A higher risk will be associated with exhibits containing objects of high monetary or cultural value.
- At a minimum, alarms should be hard-wired to a monitoring company or the local police, with a power backup in case of power failure.
- An open exhibit faces a higher risk of theft and incidental touching. These can be deterred by electronic monitoring devices. For example, proximity detectors can be used to warn visitors that they have crossed a threshold, i.e. they are now too close to a painting or have ventured too far into an historical room.
- A lending institution may require specific security features and these specifications must be accommodated.
What different types of security hardware are available?
Security hardware falls into two broad categories:
- Mechanical deterrents that can be used on cases, such as security glazing, tamper resistant fasteners and locks. * [For more information on case security, see Standard *.]
- Electronic monitoring devices that can be used on cases or in the open exhibit space to alert staff or police to a potential threat.
What types of electronic monitoring devices are available?
Sensors and alarms can be included on doors, windows, skylights, cases, platforms, and even on individual large objects. Sensors fall into two main categories: Sensors that detect movement of an object and sensors that detect a boundary has been crossed:
- Magnetic Contact Sensors or Micro-switches: Electrical circuits installed underneath an object signal remotely or locally when the object is moved.
- Vibration switches: A sound is produced when the object undergoes mechanical vibration. If the object is merely set off balance the sound will cease, but if removed the sound will continue.
- Weight Sensors: These sensors are set underneath a shelf and are controlled by the combined weight of the object or objects on the shelf and respond to any reduction in that weight.
- [Name?] Devices: The presence of magnetic or microwave fields that show a frequency shift if an object is moved. They can be unobtrusively positioned within a display case to fill the entire volume of the case.
- Audio Sensors: These systems use microphones that work on the principle of changes in charge that take place when the distance between two capacitor plates changes due to mechanical vibration or changes in air pressure.
- Magnetic Reed Switch: Consists of contacts, impervious to external influence, located in glass or plastic that are controlled by a prescribed external, magnetic field. [Clarification needed]
- Photoelectric Eyes: These form a protective screen around displayed objects consisting of laser beams passing between transmitters and receivers. An alarm signal is generated when the beam is interrupted.
- Motion Detectors: Any intrusion changes the resonant frequency of a reference electrical field, producing a signal.
- Pressure sensors: A semi-conductor that stabilizes at a specific pressure implanted into a wall; the sensor is activated by an increase or decrease in the pressure of 5 grams or more. Weight sensors are useful for objects outside of a case like a painting.
- Built-in Wires: Wire circuits that trigger an alarm when broken are useful for objects located outside a case like paintings and oversized objects.