As technology advances, Charged Device Model (CDM) damage model is growing to be a new ESD sensitive device killer.
One of the sources for CDM damage model is from the ESD garment worn by the personnel. As a result, the control on ESD garment or ESD smock has gained a growing importance.
ESD garments or ESD smocks become tribocharged when worn by the personnel. Besides providing shielding protection,the conductive threads which were sewn on the ESD garment help to dissipate the static charge to ground either through the ground wire attached to the garment or through the contact between the ESD garment and a grounded human body.
ESD garments or ESD smocks will not be able to function properly if the conductive threads on the ESD garments/smocks become damaged.
As a result, the ESD garments/smocks must be periodically tested to maintain the integrity of ESD property.
For any organization with a large number of employees, it would definitely be difficult to ensure full compliance on ESD garments/smocks according to ANSI/ESD S20.20 /IEC 61340, unless there is a systematic approach to monitoring the ESD garments/smocks.
Unless you have a systematic approach to monitor the ESD garments/smocks in your organization, you may want to consider "Automated ESD garment tester" which is an automated ESD garment/smock tester that runs on auto-pilot.
ESD garment or ESD smock tester
Is Electrostatic Contact Voltmeter a necessary equipment for ESD Coordinator?
For Most experienced ESD Coordinators, they know the build up of electrostatic charges
and their discharge to ground very quickly is the cause of ESD problems.
In the process of making the Electrostatic Discharge Sensitive (ESDS) devices, there will be a series of contact and separation of the ESDS device with other materials.
Static charges constantly build up and discharge along the way during the process until they are completely packaged into the ESD bags.
Too much electrostatic charges on the ESDS device may be harmful and it is harmful if the voltages on them exceeding their CDM (Charge Device Model) withstand voltage level.
It is extremely difficult to measure voltage on the ESDS devices which are getting smaller each day, and thank God, the solution to the problem is now available in the market place.
Industry ESD Specialists have come up with very handy electrostatic measuring tools for any ESD Coordinator at work.
An Electrostatic Contact Voltmeter with high input impedance ( > 1E14 ohm )and low input capacitance (=< 20pF) allows an accurate measurement of the existence of electrostatic charges on the ESDS device in Volt as there will be NO electrostatic charges transfer to/from the measured ESDS device.
Some of recommended Electrostatic Contact Voltmeters in the market place are:
CVM-780 Prostat Contact Voltmeter
Input impedance >= 1E14 ohm
Input capacitance < 1pF
See how CVM-780 Prostat Electrostatic Contact Voltmeter Can Do for You Here.
Infinitron™ from Trek.Inc
Input impedance >1E16 ohm
Input capacitance < 0.001pF
Ultra High Impedance Contact Voltmeter from Trek, Inc. is Here.
The Electrostatic Contact Voltmeter not only allows ESD Coordinator measure voltage on ESDS device but also voltage on the conductive parts of equipment that come into contact with ESDS device.
Monitoring the ESD process by measuring the electrostatic voltage on ESDS device with Electrostatic Contact Voltmeter is a good way to start. This is another way to ensure the ESD processes are doing fine and not causing any ESD problems to your ESDS device.
