What must be verified before any propane container can be refilled?

Before refilling a propane container, it is critically important to verify that there are no ignition sources within 25 feet. This safety measure is in place to prevent accidents and ensure the safe handling of propane, which is highly flammable. By removing potential ignition sources, the risk of fire or explosion during the refilling process is significantly minimized, creating a safer environment for both the personnel handling the propane and those nearby.

The other options do not adequately address this urgent safety concern. While the cleanliness of any equipment used may be important, polishing parts is not a required step for refilling containers. Filling a container with water is irrelevant to the refilling process and does not meet industry standards or safety practices. The age of the container must be considered; however, it is the verification of safety distances from ignition sources that is paramount in this scenario.