California ICC UST Inspector Practice Exam

What is the maximum allowable probability of false alarm for automatic line leak detectors?

1. 1%

2. 2%

3. 5%

4. 10%

The correct answer is: 5%

The maximum allowable probability of false alarm for automatic line leak detectors is 5%. This standard is in place to ensure that leak detection systems are both reliable and effective. A false alarm probability of up to 5% suggests that while the system is designed to detect actual leaks, there will be a reasonable allowance for occasional false alarms, which helps to balance safety with operational practicality. Setting the threshold at this level helps in minimizing unnecessary shut-downs or maintenance interventions resulting from false alerts, while still maintaining a robust response to genuine leaks. This balance is essential as over-sensitive detectors could lead to alarm fatigue, where staff may begin to disregard alarms that are more likely to be false. Thus, ensuring that the probability of false alarms does not exceed 5% is critical for maintaining both safety and operational efficiency in monitoring underground storage tanks.