has a low battery monitor which identifies when the batteries need to be replaced, this monitor may fail to operate as expec-
ted. Regular testing and maintenance will keep the system in good operating condition.
Compromise of Radio Frequency (Wireless) Devices
Signals may not reach the receiver under all circumstances which could include metal objects placed on or near the radio
path or deliberate jamming or other inadvertent radio signal interference.
System Users
A user may not be able to operate a panic or emergency switch possibly due to permanent or temporary physical disability,
inability to reach the device in time, or unfamiliarity with the correct operation. It is important that all system users be trained
in the correct operation of the alarm system and that they know how to respond when the system indicates an alarm.
Smoke Detectors
Smoke detectors that are a part of this system may not properly alert occupants of a fire for a number of reasons, some of
which follow. The smoke detectors may have been improperly installed or positioned. Smoke may not be able to reach the
smoke detectors, such as when the fire is in a chimney, walls or roofs, or on the other side of closed doors. Smoke detectors
may not detect smoke from fires on another level of the residence or building.
Every fire is different in the amount of smoke produced and the rate of burning. Smoke detectors cannot sense all types of
fires equally well. Smoke detectors may not provide timely warning of fires caused by carelessness or safety hazards such
as smoking in bed, violent explosions, escaping gas, improper storage of flammable materials, overloaded electrical circuits,
children playing with matches or arson.
Even if the smoke detector operates as intended, there may be circumstances when there is insufficient warning to allow all
occupants to escape in time to avoid injury or death.
Motion Detectors
Motion detectors can only detect motion within the designated areas as shown in their respective installation instructions.
They cannot discriminate between intruders and intended occupants. Motion detectors do not provide volumetric area pro-
tection. They have multiple beams of detection and motion can only be detected in unobstructed areas covered by these
beams. They cannot detect motion which occurs behind walls, ceilings, floor, closed doors, glass partitions, glass doors or
windows. Any type of tampering whether intentional or unintentional such as masking, painting, or spraying of any material
on the lenses, mirrors, windows or any other part of the detection system will impair its proper operation.
Passive infrared motion detectors operate by sensing changes in temperature. However their effectiveness can be reduced
when the ambient temperature rises near or above body temperature or if there are intentional or unintentional sources of
heat in or near the detection area. Some of these heat sources could be heaters, radiators, stoves, barbeques, fireplaces,
sunlight, steam vents, lighting and so on.
Warning Devices
Warning devices such as sirens, bells, horns, or strobes may not warn people or waken someone sleeping if there is an inter-
vening wall or door. If warning devices are located on a different level of the residence or premise, then it is less likely that
the occupants will be alerted or awakened. Audible warning devices may be interfered with by other noise sources such as
stereos, radios, televisions, air conditioners or other appliances, or passing traffic. Audible warning devices, however loud,
may not be heard by a hearing-impaired person.
Telephone Lines
If telephone lines are used to transmit alarms, they may be out of service or busy for certain periods of time. Also an intruder
may cut the telephone line or defeat its operation by more sophisticated means which may be difficult to detect.
Insufficient Time
There may be circumstances when the system will operate as intended, yet the occupants will not be protected from the
emergency due to their inability to respond to the warnings in a timely manner. If the system is monitored, the response may
not occur in time to protect the occupants or their belongings.
Component Failure
Although every effort has been made to make this system as reliable as possible, the system may fail to function as intended
due to the failure of a component.
Inadequate Testing
Most problems that would prevent an alarm system from operating as intended can be found by regular testing and main-
tenance. The complete system should be tested weekly and immediately after a break-in, an attempted break-in, a fire, a
storm, an earthquake, an accident, or any kind of construction activity inside or outside the premises. The testing should
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