DESCO WEST
- 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178
DESCO EAST
- One Colgate Way, Canton, MA 02021-1407 • (781) 821-8370 • Website:
Desco.com
TB-3062
Page 4 of 8
© 2013 DESCO INDUSTRIES, INC.
Employee Owned
• Push and hold the Test Button until the surface
resistance mantissa is displayed.
Measure Resistance to Ground (Rtg)
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 black test lead to a grounded point.
• Use one 5 pound electrode on the other test lead and
place the electrode on the furthest convenient point on
the surface.
• Push and hold the Test Button until the surface
resistance mantissa is displayed.
• Perform additional measurements by placing the
electrode on the most commonly used or worn area. Set
the meter to QUICK test mode to skip the 15 second
period if preferred.
If the measurement is outside acceptable limits, clean the
surface with an ESD cleaner containing no insulative silicone
such as
Reztore™ Antistatic Surface & Mat Cleaner
, and
re-test to determine if the cause of failure is an insulative dirt
layer or the ESD worksurface material.
• Perform additional measurements by placing the
electrode on the most commonly used or worn area. Set
the meter to QUICK test mode to skip the 15 second
period if preferred.
If the measurement is outside acceptable limits, clean the
surface with an ESD cleaner containing no insulative silicone
such as
Reztore™ Antistatic Surface & Mat Cleaner
, and
re-test to determine if the cause of failure is an insulative dirt
layer or the ESD worksurface material.
Figure 5. Rtg test setup
Figure 6. Rtt test setup - set the electrodes about 10"
apart for worksurfaces and about 36" apart for flooring
10"
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 pound electrodes and place them on the most
commonly used area of the surface. Ensure that the
electrodes are about 10" apart from each other and 2"
away from any edge and 3" away from any grounded
point.
• Push and hold the Test Button until the surface
resistance mantissa is displayed.
• If the most used area is not obvious, use two points near
the center of the surface.
Reporting and Using Test Results
Different standards have different requirements; however,
follow the 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
Per ANSI/ESD 7.1 (Floors), report:
• Rtg all values in ohms for resistance-to-ground
• Rtt all values in ohms for point-to-point resistance
• Voltage level
• Test date
• Temperature
• Relative humidity
• Test equipment used and latest calibration date
Summarize the test data by reporting the minimum,
maximum, median and mean values that were obtained.
Include a diagram showing the approximate electrode
positions and ground connections used.
