Propane supply line clearance

I inspected a house which has a wall heater that vents through the exterior wall. The vent is located about 6 inches from where the main propane line enters the home. The guy who filled the propane tank said this was a concern. I can’t find any requirements regarding this condition. Any thoughts.

There are no clearance requirements for gas lines and heat vents.

Thanks. I appreciate the response.

Is it a direct vent - taking air in for combustion as well exhausting? If so there might be an issue check your AHJ. Ditto for any fresh air intakes close to propane equipment.