Which of the following is a safety concern for unprotected underground piping?

Corrosion from external sources is a significant safety concern for unprotected underground piping. When piping is buried underground, it is often exposed to moisture, soil chemicals, and other environmental factors that can promote corrosion over time. This deterioration can weaken the structural integrity of the pipes, increasing the likelihood of leaks and potential failures.

Corrosion can be exacerbated by various elements in the soil, such as salts, which can create a corrosive environment. These leaks can lead to the release of natural gas, posing serious risks such as explosions and environmental contamination.

Therefore, protecting underground piping from corrosion is essential in maintaining safety and ensuring the reliable transport of compressed natural gas. This often involves employing protective coatings, cathodic protection systems, or choosing materials that are resistant to corrosion. Understanding and addressing this issue is crucial for anyone working with or responsible for underground pipelines.