Operation
32
Static Electricity and Filling the Gasoline Tank
Static electricity can initiate from ungrounded gasoline tanks or containers, from flowing gasoline, and from persons
carrying a static electric charge.
Static electricity can explosively ignite gasoline vapors that are present during the fueling process, resulting in serious
burns to nearby persons. To avoid static electricity while fueling, certain steps must be followed before and during the
fueling process to minimize and safely dissipate static charge build-up:
•
Touch a grounded metal object before starting
. Always dissipate static charge from your body before beginning
the fueling process by touching a grounded metal object at a safe distance away from fuel sources.
•
Use a portable container to fill tank
. Never fill the generator’s gas tank directl
y from the fuel pump
–
the
generator’s tank is not grounded and the high velocity flow of gasoline from a fuel pump can cause static electric
build-
up. Use an approved portable container to transfer gasoline to the generator’s tank.
•
Fill container on the ground.
Never fill the portable gas container while it is sitting inside a vehicle, trailer, trunk,
or pick-up truck bed. ALWAYS place container on the ground to be filled.
•
Keep nozzle in contact with container
. Keep nozzle in contact with the portable container at all times while
filling. Manually control the flow of gasoline; do NOT use the nozzle’s lock
-open device.
•
Use a portable container made of metal or conductive plastic.
It will dissipate charge to ground more readily.
About static electricity and fueling
Many common objects can accumulate and retain a static electric charge. Objects made of non-conductive materials
(e.g. plastics) easily accumulate and retain static electric charge, as can objects made of conductive material (e.g. metal,
water) if they are not electrically grounded. The static electric charge on an object, such as a human body or plastic fuel
tank/container, can reach as high as several thousand volts!
A static electric spark can be generated if the static electric char
ge stored on an object “jumps” to another, less charged
object. Such a spark can ignite invisible gasoline vapors that are present during fueling situations.
Typical sources of static electric hazards during fueling
The following objects can accumulate a static electric charge and cause an ignition spark in typical fueling situations:
•
Ungrounded tanks/containers. Any ungrounded fuel tank or container can accumulate a static electric charge as a
result of contact with other objects or friction during transportation. This static electricity can discharge as a spark to
the grounded gasoline dispenser nozzle, as the nozzle is first brought close to the tank/container at the beginning of
the fueling process.
•
Flowing gasoline. Most people are not aware that gasoline accumulates static electric charge while flowing through a
hose or pipe. This charge then transfers to and accumulates in the gas tank or container that is being filled. The total
amount of charge accumulation depends on the amount of gas pumped into the container, the speed with which it is
pumped, and whether or not the tank/container is grounded. If sufficient static electric charge accumulates in the fuel
tank or container during the fueling process, the tank/container may discharge a spark to the grounded gasoline
dispenser nozzle.
•
Persons. A person dispensing the gasoline can carry a static electric charge on their body, typically resulting from
contact with their car seat or electronics. The static electricity can discharge as a spark b
etween that person’s hand
and either the grounded dispenser nozzle or the fuel tank opening.
