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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.