Under what circumstances should artificial illumination be restricted to safety-type flashlights?

The correct answer emphasizes the importance of safety when working on piping that contains gas. When there’s potential exposure to flammable gases, it is crucial to use equipment that minimizes ignition risks. Safety-type flashlights, which are designed to prevent sparking, are appropriate in these situations because they reduce the chance of igniting any gas leaks that might be present.

Using regular illumination sources in areas where gas is present could lead to dangerous situations, including explosions or fires, due to the ignition of flammable vapors. Therefore, restricting artificial light to safety-type flashlights is vital for maintaining safety protocols and protecting personnel from hazardous situations.

In contrast, the other circumstances listed—maintenance, working in confined spaces, and inspections—can also present risks, but the direct link to the presence of flammable gas makes working on gas-containing piping particularly critical in adhering to safety regulations surrounding artificial illumination.