TB-3014
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DESCO WEST
- 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178
DESCO EAST
- One Colgate Way, Canton, MA 02021-1407 • (781) 821-8370 • Website:
Test Lab Test Procedure Guideline
For test lab use of ESD Worksurfaces, Floor Materials,
Footwear, Garments, or Seating, best advice is to follow
test methods in applicable ESD Association documents
(see above) which include details such as:
• Cleaning (For example per S4.1, “The test specimens
and electrodes shall be cleaned twice with a minimum
70% isopropanol-water solution using a clean, low-linting
cloth each time). Allow to dry.
• Environmental chamber (For example per S4.1, control
relative humidity to 12 ±3% RH and 50 ±5% RH and
temperature to 23 ±1 degrees C)
• Specimen support surface (For example per S4.1,
greater than 1.0 x 10E12 ohms such as PMMA, PTFE or
polycarbonate)
• Specimen Pre-Conditioning (For example per S4.1, at 23
±1 degrees C; 3 specimens at 12 ±3% relative humidity
for up to 72 hours minimum, and 3 specimens at 50 ±5%
relative humidity for up to 72 hours minimum)
• Reporting Test Results, for example per S4.1 Reporting
Test Results, Report:
• Minimum, median and maximum readings for both
resistance-to-groundable point and point-to-point
resistance in ohms at low relative humidity
• Minimum, median and maximum readings for both
resistance-to-groundable point and point-to-point
resistance in ohms at moderate relative humidity
• Temperature
• Relative humidity
• Actual duration of conditioning
• Test equipment used
Compliance Verification Test Procedure
Guideline
The ESD Association lists test procedures and
troubleshooting tips in Compliance Verification ESD TR53.
Measure Rtg Resistance to Ground
Test Procedure in accordance with ANSI/ESD S4.1 section
6.4 Periodic Worksurface Testing:
• Do not clean the surface
• Remove from the surface only those items that might
interfere with the test.
• ESD sensitive devices shall also be removed
• Clip the sensing test lead with shielded plug to
groundable point connected to ground
• Use one 5# Electrode on other test lead and place
Electrode the farthest convenient point on the surface
• Press button and hold Test Button until measurement is
displayed
• Perform additional measurements placing Electrode on
the most commonly used or most worn area
If measurement is outside acceptable limits, clean surface
and retest to determine if cause of failure is insulative dirt
layer or the ESD worksurface material. Note: Use an ESD
cleaner containing no insulative silicone (i.e. Reztore™
Antistatic Surface and Mat Cleaner).
Measure Resistance Point-to-Point (Rtt) on the
Surface
• Do not clean the surface
• Remove from the surface only those items that might
interfere with the test.
• ESD sensitive devices shall also be removed
• Use two 5 opund electrodes, place in the most commonly
used portion of the surface about 10” apart (2” from any
edge, 3" from any groundable point)
• Press button and hold Test Button until measurement is
displayed
• If the most used portion is not obvious, use two points
near the center of the surface
If measurement is outside acceptable limits, clean surface &
retest to determine if cause of failure is insulative dirt layer
or the ESD protective product. Note: Use an ESD cleaner
containing no insulative silicone (i.e. Reztore™ Antistatic
Surface and Mat Cleaner)
© 2013 DESCO INDUSTRIES INC.
Employee Owned
Figure 3. Setting up for RTG testing.
10”
Figure 4. Setting up for Rtt testing.
Reporting and Using Test Results
Different standards have different requirements; follow
requirements as specified in the user’s ESD control plan.
Examples are:
Per ANSI/ESD 4.1 (worksurfaces), Report:
• Rtg maximum and minimum values measured for
resistance-to-ground in ohms
• Rtt maximum and minimum values measured for
point-to-point resistance in ohms
