To reduce the risk of fuel connections leaking, any connection which permanently carries fuel must be made with efficient screwed, compression, cone brazed or flanged joints (see diagram - Fuel connections in rigid fuel pipework). Soft soldered and push-on joints will quickly fail if exposed to excess heat, potentially adding more fuel to a fire. They must not be used. Where flexible hoses are connected to rigid components of the fuel system, e.g. pipes and filters, the connections must be made with metallic clamps onto proper hose nozzles. It's not acceptable to just push a flexible hose over the bare end of a rigid pipe - even if a clamp is used! [2.15]