Red Seal Gasfitter — Class A Practice Exam

How are natural gas leaks typically detected?

1. By odor, which is added to the gas, or using gas detectors

2. By visual inspection of the pipes

3. Using a specialized gas meter

4. Auditory signals from the appliances

The correct answer is: By odor, which is added to the gas, or using gas detectors

Natural gas is naturally odorless, which means that for safety reasons, an odorant is added to detect leaks. This odorant, typically mercaptan, has a distinct smell similar to rotten eggs, making it easily recognizable. When a leak occurs, the presence of this odor provides a quick and effective means for individuals to detect it and respond appropriately, usually by evacuating the area and contacting emergency services. In addition to this visual cue from the odor, gas detectors are widely used in both residential and commercial settings. These detectors constantly monitor for the presence of natural gas in the air and can alert occupants to potentially hazardous situations, even at low concentrations that might not be perceptible by smell. This dual approach of using both odorization and detectors increases safety and ensures that gas leaks can be identified promptly before they lead to more serious incidents. Other detection methods, such as visual inspection or specialized gas meters, do have their place in maintenance and leak detection but are not as immediate or effective for general leak detection as the combination of odor and gas detectors. Visual inspections may miss leaks that are hidden or in hard-to-reach areas, while specialized gas meters are typically used in more controlled environments by professionals rather than for immediate detection by the general public. Aud