HP EliteBook 720 G1 Maintenance And Service Manual page 76

CAUTION:
observe these precautions:
Keep components in their electrostatic-safe containers until you are ready to install them.
Before touching an electronic component, discharge static electricity by using the guidelines described in this
section.
Avoid touching pins, leads, and circuitry. Handle electronic components as little as possible.
If you remove a component, place it in an electrostatic-safe container.
The following table shows how humidity affects the electrostatic voltage levels generated by
different activities.
CAUTION:
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
64 Chapter 4 Removal and replacement preliminary requirements
To prevent damage to the computer when you are removing or installing internal components,
A product can be degraded by as little as 700 V.
Typical electrostatic voltage levels
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
Relative humidity
40%
15,000 V 7,500 V
5,000 V 3,000 V
800 V 400 V
700 V 400 V
4,000 V 2,000 V
5,000 V 3,500 V
20,000 V 7,000 V
11,000 V 5,000 V
55%