A: As is often the case in ESD, the obvious solution sometimes covers up hidden dangers. The task here is simply to make that basic electrical connection from the cabinet to a common-point ground. Something as basic as a clamp or bolt connection would seem to fit the bill. The challenge is in assuring that the cabinet or shelving is indeed grounded and that all parts are grounded.

Why such a challenge? First, these are painted metal cabinets. Although the metal underneath is obviously a conductor, the paint on the surface is usually an insulator. If your ground connection makes contact only with the paint and not with the metal, you may not be adequately grounded. You may need to sand away some paint at the point where you are making the ground connection.

Second, what is the electrical continuity between the drawers or the shelves to the frame? Do the drawers contact the metal frame via insulating glides? Do the shelves sit on insulating supports? If so, they are not grounded if the ground is connected to the frame alone. You may need to replace these glides and supports with conductive ones, or electrically connect the drawers and shelves to the frame in some other fashion.

Some companies may rely on the cabinet's being in contact with a static-control floor or mat for grounding. Again, there is the possibility that the bottom of the cabinet has casters or floor protectors that insulate the cabinet from the floor.

The approach to ESD grounding of cabinets and shelves is the same as for equipment, work surfaces, floors, and even wrist straps: be certain that you have good electrical continuity from and between all parts of the item being grounded. And be certain that the grounding procedure being used doesn't compromise personnel safety in the area.

A: High-voltage environments tend to create some unique situations for ESD control because many of our control procedures have the possibility of compromising personnel safety in these environments. A key procedure is to be sure to follow all electrical and safety codes. You can find information in the National Electrical Code (ANSI/NFPA 70) and the IEEE Green Book (ANSI/IEEE Std. 142).

Another source of information is your own safety department. Be sure to enlist it in your activities so you can provide both safety and ESD control.

Additional information may be obtained by contacting the ESD Association, 7900 Turin Rd., Bldg. 3, Ste. 2, Rome, NY 13440; phone: 315/339-6937; fax: 315/339-6793; Internet: http://www.eosesd.org; e-mail: eosesd@aol.com.