What is one of the common types of disturbances that can lead to false PIR alarms?

Rodents can indeed lead to false alarms in Passive Infrared (PIR) sensors. These sensors detect changes in infrared radiation, which is primarily produced by warm bodies. Since rodents are larger than many other types of small animals and move within the detection field, their movement can trigger the sensor.

While other factors, such as heavy rain, snow accumulation, or low battery power, can also contribute to disturbances or issues in alarm systems, they typically do not trigger PIR sensors in the same way that the movement of warm-bodied animals does. Heavy rain can create noise in the environment or cause water to accumulate, but it generally will not generate the same kind of infrared signature as a warm-bodied animal. Snow accumulation might block the sensor altogether or create a false sense of security. Low battery power could lead to performance issues or sensor failure, but it does not create a false alarm as it does not produce a detectable infrared signal. Therefore, among the options provided, rodents are the most common cause of false alarms for PIR sensors, making this option particularly relevant.