California ICC UST Inspector Practice Exam

Leak detection methods must be able to detect the specified leak rate with a probability of detection of at least what percentage?

1. 90%

2. 99%

3. 0.005%

4. 95%

The correct answer is: 95%

Leak detection methods for underground storage tanks (USTs) are critical components of environmental safety and regulatory compliance. The specified leak rate must be reliably detected to prevent the escape of hazardous substances into the environment. A probability of detection of at least 95% demonstrates a high level of confidence in the leak detection methods used. This means that if there is indeed a leak at the specified rate, the detection system is expected to identify it correctly in at least 95 out of 100 instances. This threshold is widely accepted in both regulatory frameworks and industry best practices, ensuring that USTs are effectively monitored and that environmental risks are minimized. Choosing a probability higher than 95%, such as 99%, may be overly cautious and could potentially lead to increased operational costs without significantly improving safety outcomes. Conversely, opting for a lower probability of detection could lead to inadequate monitoring and heightened risks of environmental contamination. Therefore, a 95% detection probability strikes an appropriate balance between reliability and practical operational concerns.