ESD Journal Approved Tests Method
ATP Triboelectric T-1000
March 11, 2003
The Naval Weapons Laboratory used this
test as early as the 1960's for evaluation of garments used in electrostatically
sensitive areas, especially in the handling of primary explosives.
It has been used by Brunswick for the development of upholstery
fabrics and is now used by at least two ESD Labs for testing of
fabrics and garments: Fowler Associates and K&S Labs.
This tests method is intended to determine
the potential on a person wearing garments made from various fabrics
who has been rubbed across the person's back with the material under
test. Variations of this test may include the subject wearing a
test garment and being rubbed by a various range of fabrics. This
test method may also be used to determine the potential on a test
material when rubbed on a test subjects clothed back.
Procedure: This test method
requires two technicians: an operator and a test subject.
The operator folds a "scarf"
of rubbing material to a size of about 5' long by 5" wide.
test subject stands on any insulative surface ( greater than 1E13
Ohms) and holds a lead or wears a wrist strap with no resistor which
connects to a suitable high impedance recording volt meter, e.g.,
a charged plate monitor.
The test subject grounds himself and
the operator neutralizes any surface charges from the test subject's
back, tests materials and soles of the test subject's shoes. The
feet of the test subject must be kept still during the test.
The operator grasps the scarf near
the ends, first ionizing it to remove any residual charges from
handling. The operator then smartly strokes the upper back of the
test subject five times in the manner of a shoe shine rag polishing
a shoe. After the last stroke, the operator quickly steps back away
from the test subject to a distance of three to five feet to exclude
the effect of the field coming from the scarf.
The criterion of static is the maximum
body potential on the test subject.
While this test was originally used
to qualify personnel garments, it is equally useful in measuring
the performance of, for example, upholstery material, in which case
various upholstery scarves are used against various clothing or
draped cloth materials. Some suggested clothing and seat materials
Denim, Linen, Silk, Rayon, Wool,
Rayon/PE, Cotton & Polyester
indexing is a little difficult due to the wide variations in the
way that people slide and stand up, differences in shoes and floor
coverings, etc. However, the maximum voltage achieved in this test
is an excellent ranking parameter and can be tailored to closely
approximate worst-case real life conditions.
The additional measurement of the potential
on the scarf material may also yield useful information. This may
be accomplished with or without the operator wearing gloves for
isolation of the scarf material. For this measurement, the scarf
material is immediately after the strokes, held in front of a non
contacting volt meter and the volts/inch recorded.
These tests are intended to be carried
out at 12% RH, 720 F after 72 hours of conditioning at these conditions.