Sec. 1276.4. Operation

(a) Vehicle motors.

Motors of tank vehicles shall not be run during cargo tank filling, making or breaking filling connections, or during fuel handling system repairs. The propulsion motor for refueling service vehicles shall not be run during fuel transfer, making or breaking of hose connections.

(b) Maximum cargo volume.

No cargo tank compartment shall be completely filled. There shall be sufficient space remaining to allow for expansion of the contents to prevent distortion or leakage, and in no case shall the free space be less than two percent of the capacity of the tank. Each tank compartment shall be fitted with a sealed gauge marker set to indicate the maximum permissible capacity.

(c) Attendants.

The driver, operator or attendant of any tank vehicle shall be in attendance with the vehicle at all times when the vehicle is fueling or refueling an aircraft. Such person shall not leave the tank vehicle to handle hose for overwing refueling or fuel from a work stand in excess of six feet in height or in a position more than 50 feet from the tank vehicle unless a firewatch, familiar with the operation, is on hand on the ground. A firewatch shall not serve more than two vehicles or two aircraft under fuel servicing simultaneously and must be within 75 feet of any operation under his surveillance.

(d) Position.

During refueling or defueling, tank vehicles shall be so placed as to be readily removable in event of fire so as to permit direct driving away from the loading or fueling position. Not more than one refueler shall be positioned to refuel each wing of an aircraft; and not more than two refuelers shall be positioned to serve the same aircraft. When high capacity aircraft are refueled additional refuelers shall not be parked or positioned within 100 feet from the aircraft served and then only in areas approved by the manager.

(e) Smoking.

Smoking by any person on or within 50 feet of a tank vehicle or refueling service vehicle is prohibited.

(f) Grounding.

All tank vehicles shall be fitted with means of bonding and grounding. The maximum resistance of any static grounding or bonding circuit (bonding clips through the grounding cable, reels and chassis to the ground point) shall not exceed 100 ohms. During filling of the cargo tank, the tank vehicle shall be grounded together with the tank truck filling rack and inflammable liquid discharge piping to a point of zero electrical potential. Prior to any transfer and during refueling or defueling of aircraft, the fuel dispensing hose, nozzle, tank vehicle and the aircraft shall be bonded and grounded to a point or points of zero electrical potential (the electrical potential of the earth in the vicinity of aircraft and fuel tank vehicle). Bonding of an underwing refueling nozzle to the aircraft is not required when a metal to metal clamping contact between the nozzle and the filler connection is affected. Grounding shall be accomplished in the following manner:

(1) Attaching the ground conductor on the tank vehicle to a proper grounding rod.

(2) Attaching the ground conductor to the aircraft by use of either a Y connection or second grounding cable device.

(3) Bonding the aircraft and the dispensing nozzle or coupler connection by use of the clamp and bonding wire device attached to the nozzle prior to opening the aircraft tank and disconnecting after the aircraft tank is filled and the filler opening is closed. Under-the-wing nozzles only require bonding devices when of insulated construction preventing a firm metal to metal contact.

(g) Fire extinguishers. Each tank vehicle shall be equipped with at least two 20 pound dry chemical extinguishers. The extinguishers shall be located in an accessible place as far away as practicable from the pumping equipment. Extinguishers shall be protected by readily removable weatherproof hoods.

(h) Parking. Tank vehicles shall not be parked in public areas except as designated by the airport operator. Tank vehicles wherever parked shall be positioned for immediate drive away or towing and a clear space of not less than 15 feet shall be maintained between any tank vehicle and any similar or other vehicle. No more than four refueler tank vehicles shall be parked unattended at any one location. Where five or more vehicles are parked, a constant attendant, qualified to drive the vehicles and competent in the operation of the fire protection equipment, shall be stationed in the area observing the operation and 150 pound dry chemical wheel type fire extinguishers shall be positioned so one or more units will be within 100 feet travel distance from any parked vehicle in the designated area. Satellite parking areas shall be posted from all directions with a sign legible from a 100 foot distance reading, “Danger—Aircraft Fuel—No Smoking—No Open Fire or Lights.”

(i) Markings. Each tank vehicle shall be conspicuously marked, on both sides and rear of the cargo tank in letters of contrasting color, at least six inches high, with the word “FLAMMABLE.”