Warning:
Important safety notes for telephony connections
Allow only qualified technical personnel to install NMS hardware and its associated telephone wiring.
Make sure the PC chassis is grounded through the power cord or by other means before connecting the telephone line.
If your system requires an external power supply, make sure it is grounded through the power cord or by other means.
Never install telephone wiring during a lightning storm.
Never install telephone jacks in wet locations.
Telephone companies provide primary lightning protection for their telephone lines. However, if a site connects to private lines that leave the building, make sure that external protection is provided.