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Limitations of This Alarm System
While this system is an advanced design security system, it does not offer guaranteed
protection against burglary, fire, or other emergency. Any alarm system, whether
commercial or residential, is subject to compromise or failure to warn for a variety of
reasons. For example:
Intruders may gain access through unprotected openings or have the technical
sophistication to bypass an alarm sensor or disconnect an alarm warning device.
Intrusion detectors (e.g., passive infrared detectors), smoke detectors, and many other
sensing devices will not work without batteries, or if the batteries are not put in
properly. Devices powered solely by AC will not work if their AC power supply is cut
off for any reason, however briefly.
Signals sent by wireless transmitters may be blocked or reflected by metal before they
reach the alarm receiver. Even if the signal path has been recently checked during a
weekly test, blockage can occur if a metal object is moved into the path.
A user may not be able to reach a panic or emergency button quickly enough.
While smoke detectors have played a key role in reducing residential fire deaths, they
may not activate or provide early warning for a variety of reasons in as many as 35%
of all fires. Some of the reasons smoke detectors used in conjunction with the System
may not work are as follows: Smoke detectors may not sense fires that start where
smoke cannot reach the detectors, such as in chimneys, in walls, or roofs, or on the
other side of closed doors. Smoke detectors also may not sense a fire on another level
of a residence or building. A second-floor detector, for example, may not sense a first-
floor or basement fire. Moreover, smoke detectors have sensing limitations. No smoke
detector can sense every kind of fire every time. In general, detectors may not always
warn about fires caused by carelessness and safety hazards like smoking in bed,
violent explosions, escaping gas, improper storage of flammable materials, overloaded
electrical circuits, children playing with matches, or arson. Depending on the nature
of the fire and/or the location of the smoke detectors, the detector, even if it operates
as anticipated, may not provide sufficient warning to allow all occupants to escape in
time to prevent injury or death.
Passive Infrared Motion Detectors can detect intrusion only within the designed
ranges as diagrammed in their Installation Manual. Passive Infrared Detectors do not
provide volumetric area protection. They do create multiple beams of protection, and
intrusion can only be detected in unobstructed areas covered by the beams. They
cannot detect motion or intrusion that takes place behind walls, ceilings, floors, closed
doors, glass partitions, glass doors or windows. Mechanical tampering, masking,
painting or spraying, of any material on the mirrors, windows or any part of the
optical system can reduce their detection ability. Passive Infrared Detectors sense
changes in temperature; however, as the ambient temperature of the protected area
approaches the temperature range of 90º to 104º Fahrenheit (32º to 40º Celsius), the
detection performance can decrease.
