Typical Electrostatic Voltage Levels

Removal and Replacement Preliminaries

Table 4-1 shows how humidity affects the electrostatic voltage levels generated by different activities.

Table 4-1

Relative Humidity

Event	10%	40%	55%

Walking across carpet	35,000 V	15,000 V	7,500 V

Walking across vinyl floor	12,000 V	5,000 V	3,000 V

Motions of bench worker	6,000 V	800 V	400 V

Removing DIPS from plastic tube	2,000 V	700 V	400 V

Removing DIPS from vinyl tray	11,500 V	4,000 V	2,000 V

Removing DIPS from Styrofoam	14,500 V	5,000 V	3,500 V

Removing bubble pack from PCB	26,500 V	20,000 V	7,000 V

Packing PCBs in foam-lined box	21,000 V	11,000 V	5,000 V

✎ A product can be degraded by as little as 700 V.

Table 4-2 lists the shielding protection provided by antistatic bags and floor mats.

Table 4-2

Material	Use	Voltage Protection Level

Antistatic plastic	Bags	1,500 V

Carbon-loaded plastic	Floor mats	7,500 V

Metallized laminate	Floor mats	5,000 V


Maintenance and Service Guide		4–7