HP TC1000 - Tablet PC - Crusoe TM5800 1 GHz Maintenance And Service Manual page 90

Removal and Replacement Preliminaries
Table 4-1 shows how humidity affects the electrostatic voltage
levels generated by different activities.
Event
Walking across carpet
Walking across vinyl floor
Motions of bench worker
Removing DIPS from plastic tube
Removing DIPS from vinyl tray
Removing DIPS from Styrofoam
Removing bubble pack from PCB
Packing PCBs in foam-lined box
✎
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.
Material
Antistatic plastic
Carbon-loaded plastic
Metallized laminate
4–8
Typical Electrostatic Voltage Levels
Static-Shielding Materials
Use
Bags
Floor mats
Floor mats
Table 4-1
10%
35,000 V
12,000 V
6,000 V
2,000 V
11,500 V
14,500 V
26,500 V
21,000 V
Table 4-2
Voltage Protection Level
1,500 V
7,500 V
5,000 V
Maintenance and Service Guide
Relative Humidity
40%
15,000 V
5,000 V
800 V
700 V
4,000 V
5,000 V
20,000 V
11,000 V
55%
7,500 V
3,000 V
400 V
400 V
2,000 V
3,500 V
7,000 V
5,000 V