There are several symbols that are most commonly used for ESD labels. All of the symbols have different meanings but are still related to each other.
The best-known symbol, above, was made in order to show that the device is sensitive to ESD and you should not touch it. The triangle itself tells people to take caution of whatever it is, it is essentially a universal symbol. The hand with the slash through it clearly means, "do not touch".
This second symbol is put on materials that protect other things from ESD. Examples of this are certain wristbands, which have a cord that will touch the floor as you work on your computer. This is done in order to keep you grounded and keep your electrical potential grounded in the process. Other examples include certain floor mats and chairs. Once again, the triangle warns people to take caution, however, the hand with no slash through it informs others that it is okay to touch. The semi-circle surrounding the picture means protection, in this case it notifies others that the material they are about to touch is ESD protective.
This symbol, as it says on the image, is to notify people of the ESD Common Point Ground. This point is the grounding point that receives and grounds all components of the work area such as the work surfaces, the people working, the equipment, and everything else, to one common point. Once each component of the work area is connected to this common ground point, the risk of ESD is greatly reduced.
The fourth symbol shown, shown above, is a more abstract depiction of the impact of static charges on equipment. This symbol uses three arrows and a black circle. Created originally as part of a military standard, it has been superseded officially by the reach-reach in symbol. Yet, it is still very popular in industrial use and, in fact, remains a best seller. Not everyone believes that the other symbols are as clear.
Symbols have a life of their own. Once learned, they become part of our vernacular. With, literally, 100's of millions of ESD labels in use, it is easy to see why symbols have such "staying power".
On the other hand, to be effective symbols often need to be reinforced with text. For abstract symbols (such as the radiation Trefoil, the Biohazard symbol or the various ESD symbols shown here) it is especially important to accompany the symbol with warning text.
To try to convey, with just a symbol, the many, and often subtle handling instructions is a recipe for disappointment. Accordingly, our ESD labels have a variety of legends that help you choose just the right message.