When should a fuel system be depressurized?

Depressurizing a fuel system is essential before conducting any maintenance or repair work. This procedure is critical for safety to prevent any accidental fuel leaks or explosions while the system is being serviced. Fuel systems, whether using LPG (Liquid Petroleum Gas) or CNG (Compressed Natural Gas), operate under significant pressure, and failure to depressurize appropriately can pose serious hazards to personnel and equipment.

When maintenance or repairs are underway, there's a potential for tools to come into contact with pressurized fuel lines, which could result in ignition sources or sprays of fuel. Furthermore, certain components may be sensitive to pressure variations, and handling them without depressurizing could compromise their integrity or lead to malfunction.

In contrast, depressurizing just before refueling, during routine inspections only, or when the vehicle is parked does not ensure the same level of safety as it does before actively maintaining or repairing the system. It's important to follow specific procedures for the unique circumstances of maintenance, which is why the focus is on that scenario.