This is referenced in FAA Order 8400.10 Vol 3, Chapter 15 Manuals, Procedures, and Checklists
“NOTE Grounding of the aircraft and/or fuel truck is no longer recommended because it does not prevent sparks at the fuel source, and the grounding cable may not be sufficient to discharge the electrical current.”
FAA Order 4040.9 Appendix 14 states:
“14. FUEL AND OIL SERVICING. The PIC or designated crewmember shall normally supervise fuel, oil, or other ramp services when these services are accomplished by other than FAA or qualified maintenance personnel. During fueling operations, the following safety precautions shall be observed:
a. The aircraft will be bonded by the use of a cable to the fuel truck or pit, and to the fuel nozzle.
b. Engine switches and nonessential electrical equipment shall be in the "off" position, or as dictated in the aircraft manual. Operation of an auxiliary power unit, if available while refueling, shall be governed by instructions contained in the appropriate airplane flight manual (AFM) or rotorcraft flight manual (RFM).
c. Smoking is prohibited aboard and within 100 feet of the aircraft.
d. No active radar transmitters shall be within 100 feet of the aircraft. Weather radar on the aircraft shall be turned off.
e. The correct grade of fuel has been put into the aircraft fuel tanks and the quantity received verified.
f. Fuel shall be checked for presence of water in accordance with the aircraft flight manual, pilot's operating handbook, or manufacturers' recommendations. “
Just for general bonding information the FAA recommends the following in AC 150/5210-15 Airport Rescue And Firefighting Station which calls out FAA-STD-019, Lightning Protection, Grounding, Bonding and Shielding Requirements for Facilities.
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