Table 4-1 typical electrostatic voltage levels, Table 4-2 static-shielding materials – Compaq V300 User Manual
Page 94
4-6
Removal and Replacement Preliminaries
COMPAQ CONFIDENTIAL - NEED TO KNOW REQUIRED
Writer: David Calvert Saved by: The Integrity Group Saved date: 10/26/00 11:46 AM
Part Number: 128679-006 File name: Ch04
Table 4-1 shows how humidity affects the electrostatic voltage levels
generated by different activities.
Table 4-1
Typical Electrostatic Voltage Levels
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
NOTE: A product can be degraded by as little as 700 volts.
Table 4-2 lists the shielding protection provided by antistatic bags and
floor mats.
Table 4-2
Static-Shielding Materials
Material
Use
Voltage Protection Level
Antistatic plastic
Bags
1,500 V
Carbon-loaded plastic Floor mats
7,500 V
Metallized laminate
Floor mats
15,000 V