Fowler Associates Labs

Response from Steve Fowler

In response to the question Tom Culbertson posed to the ESD Journal regarding Robert Meston's original questions about PC Monitors and Static Steve Fowler, Fowler Associates, resident expert for the ESD Journal, writes:

"The 200 volt limit was set in IEC 0015(EN10015) in Europe. I believe EIA 625 also sets such a limit. It is for any fields near a static safe area.

Is it overkill? I believe so! However, it is in place.

CRTs pose a real danger when they are unshielded or are not inherently shielded. I did an audit for a defense contractor who was having problems with tactical field radios. The final check of the circuit cards were to verify the component placement. The technician put the circuit card up to a CRT and pointed to each component. The field at the card was greater than 5,000 volts. Each grounded finger point was a potential discharge.

If a CRT has 200 volts at the screen and micro volts at the work area, I believe it is not a hazard."