Are You Complying With Fuel Regulations?
One of the most critical aspects of operating an airborne law enforcement fleet is to insure that all aspects of your fueling operations are fully compliant with applicable industry and regulatory safety standards.
Two important references for aviation fueling professionals are NFPA 407 Standard for Aircraft Fuel Servicing and ATA Specification No. 103. NFPA 407 is published by the National Fire Protection Association of Quincy, MA, while ATA 103 is published by the Air Transport Association of America in Washington, D.C.
Here is a partial checklist of safety issues outlined in NFPA 407 and ATA 103 relating specifically to jet fuel handling that you should consider in evaluating the safety of your aviation units fueling procedures:
How To Receive Jet Fuel
The receiving storage tank should always be gauged prior to delivery to verify that there is sufficient room to accept the new fuel delivery. Always connect a grounding cable to the delivery truck to prevent a difference in electrostatic potential.
After allowing the delivery truck to set for a minimum of ten minutes, conduct a Clear and Bright Test on each compartment to check for visible contaminants. In simple terms, this test is performed by drawing a minimum of one quart of fuel into a clear glass jar. The sample is then swirled to create a vortex. Visually detectable particulate matter will appear at the lower tip of the vortex. Undissolved (i.e. free) water will appear as a separate layer below the product when the swirling action stops. A hazed sample usually indicates either suspended free water or very fine particulate matter. Jet fuel ranges in appearance from no color to a definite straw color. A product free from water and suspended solids is termed Clear and Bright. If contamination remains after approximately five gallons have been sampled from each compartment, the load should be rejected.
An API Gravity Test (conducted with an ASTM hydrometer similar to the ones used to check your automotive battery) should next be conducted on incoming jet fuel. API gravity must be from 37 through 51 degrees, corrected to 60 degrees F. The API gravity read on your hydrometer should match the reading recorded on the fuel delivery manifest. If there is a variance of one degree or more from the same supplier, immediate investigation is required to determine the reason for gravity change. Typically, API gravity changes are due to contamination with small amounts of gasoline or diesel somewhere in the delivery chain (tank farm, terminal, delivery vehicle, etc.).
The sumps of all receiving tanks and filter should be drained after fuel receipt and a White Bucket test performed. To perform the White Bucket test, fill a clean, white porcelain-enameled bucket to a depth of eight inches and let the sample settle for one minute to remove air bubbles. Place the bucket on a level surface and inspect to detect the presence of water droplets, solid contaminants, hazy/cloudy conditions and/or brown slime.
Under no circumstances is it acceptable to receive and dispense fuel from the same tank simultaneously.
How To Store Fuel
Jet Fuel should only be stored in steel tanks that have an epoxy lining suitable specifically for jet fuel service.
Jet fuel storage tanks should be equipped with access manway with internal ladder, inlet diffuser and floating suction with test cable.
Jet fuel storage tanks should be equipped with a positive sump and a manual or electric-driven sump pump to remove accumulated water. A manual water drain valve (with frost protection) should also be provided on aboveground storage tanks.
Jet fuel storage tanks should be equipped with proper venting and overfill protection and alarms.
Jet fuel should be re-circulated through filtration on a regular (weekly) basis to maintain product quality. Fuel samples should be taken while the system is pressurized (flowing) to determine quality of stored product.
Proper signage is required for all jet fuel storage tanks and piping. Jet fuel identification decals employ white letters on a black background. Pipe banding of jet fuel pipelines employs a single black band.
Flammable, No Smoking, Emergency Shut-Off and other safety signage is to be provided in addition to product identification.
Jet Fuel Dispensing
Cast iron, copper and galvanized steel piping, valves and fittings are not permitted for use with aviation fuels. Ductile iron valves are permitted.
Jet fuel filter/separators should meet API 1581, Group II, Class B, Third Edition performance criteria and be minimally equipped with an air eliminator with check valve, pressure relief valve, piston-type differential pressure gauge with pushbutton, dual SS fuel sampling probes and manual water drain valve. Date of the last filter change should always be marked on the vessel. In cold weather climates, an explosion-proof, thermostatically controlled heater is recommended for installation in the filter sump housing.
Filter/Monitors are increasingly specified for jet fuel service due to the fail-safe nature of the water-absorbing element technology they employ. Filter/Monitors use what are sometimes called Go-No-Go fuses which, upon contact with water, swell and stop the fueling process thereby preventing the introduction of water contaminated fuel into the aircraft.
All aircraft fueling facilities must be designed and equipped with Emergency Fuel Shutoff Stations capable of shutting off fuel flow to all dispensing outlets. Shutoff stations (typically consisting of explosion-proof, red mushroom switches) should be located convenient to each fueling position as well as outside the probable spill area and near the route that is normally used to leave the spill area or reach the fire extinguishers provided for area protection.
All fuel dispensing systems should be equipped with a Deadman Control. For overwing refueling, this control is built into the manual overwing nozzle. For underwing (or single point) refueling, a deadman control typically consists of a control valve with a hand-held electric or hydraulic deadman handle (switch) deployed via a cable or hose reel assembly. After the underwing nozzle is locked onto the aircraft receptacle, fuel flow begins only after the deadman handle is depressed. When bottom loading refueler trucks, a deadman control in the form of a valve or electronic pump control is employed to insure that bottom loading is always an attended operation.
Static protection in the form of static cable reels should be employed to bond aircraft to refueling vehicles, carts or cabinets to prevent a difference in their electrostatic potential. A cable with a clip or plug is also required on each overwing nozzle.
Jet fuel acquires a static charge as it passes through the filter/separator. API RP2003 recommends a minimum 30-second relaxation period for the fuel downstream of the filter to allow the dissipation of the charge before introducing the fuel into a refueler tank truck. Installing a relaxation tank in the truck loading circuit or doping the fuel with Static Dissipater Additive (SDA) addresses this requirement. A typical relax tank is an ASME code vessel equipped with an air eliminator, check valve, pressure relief valve and manual water drain. Fuel relaxation is not required for aircraft refueling due to the geometry of aircraft wing tanks and the relatively few electrostatic incidents that have occurred with aircraft as opposed to refueler trucks.
All refueling hoses should comply with API Bulletin 1529 and should each be serial numbered and furnished with certified test data.
Bottom loading nozzles should be equipped with a minimum 60-mesh strainer screen.
While the above checklist of fueling system safety is not intended to be a fully comprehensive survey of recommended fueling practices, it will hopefully serve as a helpful guide in identifying where your operations can be improved and enhanced. In an environment of increasingly tight budgets and economic cutbacks, it is vital to remain focused on the basics of one of the most essential and yet dangerous aspects of airborne law enforcement-fueling system safety.
|Millennium Systems International, LLC