Special Safety Information on Static Electricity
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Static electricity and filling gasoline:
Static electricity can initiate from ungrounded gasoline tanks or containers, from flowing
gasoline, and from persons carrying a static electric charge
Static electricity on numerous occasions has explosively ignited gasoline vapors that were present during
fueling processes, resulting in serious burns to nearby persons. To avoid static electricity while fueling,
certain steps must be followed before and during the fueling process in order to minimize and safely
dissipate static charge build-up.
Filling Portable Containers at Service Stations:
Use a portable container to fill grinder tank. Never fill the grinder's gas tank directly from the service
station's fuel dispenser pump – the grinder'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 grinder's tank.
Use a portable container made of metal or conductive plastic.
It will dissipate charge to ground
more readily.
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.
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.
Keep nozzle in contact with container
. Keep fuel dispenser nozzle in contact with the portable
container at all times while filling at a service station. Do not use the nozzle lock-open device on
the dispenser hose.
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 charge 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 between that person's hand and either the grounded dispenser nozzle or the fuel tank opening.
