UL 2200-2020 pdf download – Stationary Engine Generator Assemblies.
48.2 Tanks and fuel pumps 48.2.1 Fuel tanks provided as part of the engine generator assembly shall be constructed in accordance with NFPA 37, Chapter 6, UL 142A, or ULC-S601. 48.2.2 Fittings and fill pipe longer than 0.3 m (1 ft), where soldered, welded or bonded, shall be mechanically secured to the tank in addition to soldering, welding, or bonding. 48.2.3 When a tank is within or contiguous to the engine compartment the tank location and the facilities for filling shall be such that spillage or leakage drains to the ground and not onto the engine or exhaust- system parts. Spillage tests shall be conducted when required to determine compliance. 48.2.4 A fuel tank and fill fitting shall be so located as to reduce the possibility of damage to the tank or its fittings. The fill fitting and exhaust terminus shall be at least 0.9 m (3 feet) apart when installed in accordance with the manufacturer’s instructions. The fuel fill shall not be located above the exhaust. 48.2.5 External fuel-confining parts of an electrically or mechanically operated fuel pump shall be of metal or nonmetallic material that meets the requirements of 48.4.1 and 48.4.2. Failure of operating parts shall not result in external leakage offuel. 48.2.6 Electrically-operated fuel pumps shall comply with UL 558 / ULC/ORD-C558. Exception: This requirement does not apply to electric fuel pumps that are supplied as part of and are integral to the engine, are submerged or mounted inside a non-vented container such that a pump leak cannot result in a fuel leakoutside the containerortank. 48.2.7 An automatically operated positive shutoff shall be incorporated in the fuel line. This positive shutoff shall be a part of the carburetor, fuel pump, or similar device, or shall be a separate automatic safety shutoff valve for fuel, and shall prevent fuel from flooding the carburetor or similar device and spilling into the compartment when the engine generator is not operating.
48.3 Fuel lines and fittings 48.3.1 Metallic fuel lines shall be of annealed seamless drawn aluminum or steel tubing. Flexible tubing or hose shall be used only where required to absorb vibration. 48.3.2 Aluminum tubing shall have a nominal wall thickness of not less than 0.76 mm (0.030 inch), 0.089 mm (0.0035 inch) minus tolerance. Steel tubing shall have a wall thickness of not less than 0.71 mm (0.028 inch) and shall have a corrosion-resistant exterior coating equivalent to that afforded by paint. 48.3.3 Flexible tubing or hose shall be marked to identify the manufacturer and model and shall be evaluated and found to comply with 48.4. Tubing and hose shall not pull off fittings or fail when subjected to a 89 N (20 pound-force) axial pull test applied over a 1 minute period. The test shall be conducted at ambient conditions of 21 ±5°C (70 ±9°F) with tubing or hose wetted with fuel. Hose shall be subjected to 70 hours at 100°C (212°F) aging and 48 hours of 3.175 mm (0.125 inch) amplitude vibration at 17 Hz before the pull test.