Siemens SIMATIC HMI IPC677C Operating Instructions Manual page 263

NOTICE
ESD devices can be destroyed by voltages well below the threshold of human perception.
These static voltages develop when you touch a component or electrical connection of a
device without having drained the static charges present on your body. The electrostatic
discharge current may lead to latent failure of a module, that is, this damage may not be
significant immediately, but in operation may cause malfunction.
Electrostatic charging
Anyone who is not connected to the electrical potential of their surroundings can be
electrostatically charged.
The figure below shows the maximum electrostatic voltage which may build up on a person
coming into contact with the materials indicated. These values correspond to IEC 801-2
specifications.
Figure A-1
SIMATIC HMI IPC677C
Operating Instructions, 04/2013, A5E02722710-04
Electrostatic voltages on an operator
A.2 Standards, certificates and approvals
Appendix
263