Why is static electricity a concern during propane dispensing?

• A. It has no effect on safety
• B. It can ignite leaking propane vapors; bonding and grounding minimize risk
• C. It improves sealing of connections
• D. It reduces vapor pressure

Answer: (B)

Static electricity during propane dispensing can create a spark, and that spark can ignite propane vapors if they are present. Propane vapors can leak from connections, and the transfer process can build up electrical charge on metal surfaces. Bonding and grounding provide a safe path for that charge to flow away and equalize potential between the tank, hose, nozzle, and the vehicle or dispensing equipment. By removing any significant voltage difference, the chance of a spark during fueling is greatly reduced, which is why bonding and grounding are emphasized for safety. The other ideas don’t address ignition risk or how to prevent it—bonding and grounding don’t affect sealing or vapor pressure, but they do reduce the likelihood of a static spark igniting any leaked vapor.