A wooden plank-and-beam room used for secure storage has no windows or environmental controls.

Passive infrared (PIR) sensors detect changes in infrared radiation, typically caused by the movement of objects emitting heat, such as humans. High temperatures, like those described, can saturate the sensor and reduce its effectiveness.

Impact of Temperature Variations:

If the ambient temperature matches or exceeds the body temperature of potential intruders, the sensor's ability to distinguish between the two diminishes.

Sustained high temperatures can cause sensor malfunctions or false negatives.

Other Sensor Considerations:

Microwave Sensors: Not significantly affected by temperature but sensitive to metal interference.

Ultrasonic Sensors: Work based on sound waves, unaffected by temperature changes.

Photoelectric Beam Sensors: Use light interruption and are unaffected by ambient temperature.

CPP® Context:

Physical Security Measures: Guides sensor selection based on environmental conditions and asset protection requirements.

Risk Assessment: Emphasizes evaluating environmental factors impacting security system reliability.