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ESD CONTROL PROGRAM APPENDIX C: PROTECTING AGAINST ELECTROSTATIC DISCHARGE IN EQUIPMENT ROOMS AND DISPATCH CENTERS
NOTE: Non-dissipative floor mats or chair mats should never be placed over dissipative flooring material. If
floor mats are used, they shall be of a dissipative material with a grounding conductor that is effectively
bonded to the common grounding point or the multi-point grounding system.
C.3.5 DISPATCH POSITION DESKTOPS
Work surfaces on the operator position desktops that may be touched by the operator should have a
resistance to ground measurement of between 10 6 and 10 9 ohms when measured using the test method
of ANSI/ESD -S4.1-1997 or later. If an existing desktop does not meet this requirement, an ESD
protective mat can be installed under and around the keyboard and mouse. To be effective, the ESD
protective desktop or ESD protective mat must be bonded to the operator position common grounding
point. (See ANSI T1.321-R2000, section 4.4 and ANSI/ESD S4.1-1997 for additional information.)
To help avoid ESD, the operator must touch the ESD protective desktop or ESD protective mat before
connecting to the headset jack or touching equipment or grounded objects.
C.3.6 VIDEO DISPLAY TERMINALS
If a cathode-ray tube (CRT) monitor is used, installation of a electrostatic shield such as a properly
grounded bezel or a conductive anti-glare shield that is properly bonded back to the common grounding
point will be of some benefit (ANSI T1.321-R2000). Another option is installing LCD displays, which
do not generate high electrostatic fields.
C.3.7 EQUIPMENT BONDING, GROUNDING, AND SURGE PROTECTION
All equipment, including headset jacks, located in an ESD-susceptible area, shall be properly bonded
and grounded in accordance with the requirements of “Grounding (Earthing) for Dispatch Centers and
Network Operator Positions,” on page 5-62.
Surge suppression should be provided in accordance with “Surge Protection Considerations for
Dispatch Centers and Operator Positions,” on page 7-43.
C.4 ESD CONTROL PROGRAM
After preventive measures have been implemented to help eliminate or dissipate electrostatic charges,
an effective ESD control program should be implemented to maintain the environment. For additional
information on how to establish an effective ESD control program, see Part Two - Principles of ESD
Control at the Electrostatic Discharge Association web site
(http://www.esda.org/aboutesd.html).
C-4 68P81089E50-B 9/1/05