At what temperature do the safety plugs in acetylene cylinders melt?

The correct choice indicates that the safety plugs in acetylene cylinders melt at temperatures ranging from 212 to 220 °F. These safety plugs serve a crucial purpose in preventing the hazardous consequences of excessive pressure within the cylinder. When the temperature rises and certain conditions are met, the plugs will melt, allowing acetylene gas to safely escape rather than risking an explosion or rupture of the cylinder.

This temperature range is important to ensure the safety of handling acetylene, which is highly flammable and presents significant risks if not managed properly. Knowing the specific melting point of the safety plugs helps those working with acetylene to understand the limits and safety measures necessary when storing and using these cylinders.