Until now, identifying ESD-sensitive products and ESD protective materials has been haphazard–to say the least. But since the ESD Association recently adopted a standard defining identification symbols for these items, the confusion should abate.
In the past, a number of symbols have proliferated throughout the industry, which often resulted in similar products from a number of manufacturers sporting completely different ESD labels. For example, a protective bag from one manufacturer might be identified with a lightning bolt, while another company might use a circle with three arrows to identify its protective bag.
The new ESD Standard S8.1, ESD Awareness Symbols, defines the proper symbology to use for products and materials. One symbol identifies items that are susceptible to ESD, while another identifies items that protect sensitive parts from ESD. A third symbol is used to identify an ESD common point ground.
The ESD Susceptibility Symbol consists of a triangle, a reaching hand and a slash mark through the hand (Figure 1). The triangle means caution and the slash through the hand means do not touch. This symbol is used on ICs, PCBs and assemblies that are susceptible to ESD. Improper handling of these products may result in ESD damage.
The ESD Protective Symbol consists of an arc around a reaching hand and a triangle (Figure 2). The arc around the combination forms an umbrella, which means protection. This symbol is applied to materials which provide protection from ESD, such as mats, chairs, wrist straps, garments and packaging. It also may be used on hand tools, conveyor belts, automated handlers or other equipment designed to provide ESD protection.
ESD test equipment, wrist-strap testers, resistivity meters or other equipment used in ESD control are not covered by this standard. The ESD Standards subcommittee will probably adopt an appropriate symbol for this equipment in the near future. Other revisions to the standard may include a symbol for an ESD-protective work area.
Copies of ESD Standard S8.1, including the symbols, can be obtained from the ESD Association, 200 Liberty Plaza, Rome, NY 13440, (315) 339-6937.
Copyright 1995 Nelson Publishing Inc.
April 1995