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Appendix A Net Safety M onitoring Inc. Electrosta ticSensitive Device Han dling Procedure
With the trend toward increasingly widespread use of microprocessors and a wide variety of other electrostatic
sensitive semiconductor devices, the need for careful handling of equipment containing these devices deserves
more attention than it has received in the past.
Electrostatic damage can occur in several ways. The most familiar is by physical contact. Touching an object
causes a discharge of electrostatic energy that has built up on the skin. If the charge is of sufficient magnitude, a
spark will also be vis ible. This voltage is o ften more than enough to d amage some electronic co mponents. Some
devices can be damaged without any physical contact. Exposure to an electric field can cause damage if the
electric field exceeds the dielectric breakdown voltage of the capacitive elements within the device.
In some cases, permanent damage is instantaneous and an immediate malfunction is realized. Often, however, the
symptoms are not immediately observed. Performance may be marginal or even seemingly normal for an
indefinite period of time, followed by a sudden and mysterious failure.
Damage caused by electrostatic discharge can be virtually eliminated if the equipment is handled only in a static
safeguarded work area and if it is transported in a package or container that will render the necessary protection
against static electricity. Net Safety Monitoring Inc. modules that might be damaged by static electricity are
carefully wrapped in a static protective material before being packaged. Foam packaging blocks are also treated
with an anti-static agent. If it should ever become necessary to return the module, it is highly recommended that it
be carefully packaged in the origina l carton and static protective wra pping.
Since a static safeguarded work area is usually impractical in most field installations, caution should be exercised
to handle the module by its metal shields, taking care not to touch electronic components or terminals.
In general, always exercise all of the accepted and proven precautions that are normally observed when handling
electrostatic sensitive devices.
A warning label is placed on the packaging, identifying those units that use electrostatic sensitive semiconductor
devices.
*Published in Accordance with E1A standard 471