# Safety Guidelines

Before and during the installation process, observe the following precautions:

| Warning: Do not work on the system or connect or disconnect cables during lightning activity.

| Warning: Be sure circuit breakers for the power source are in the OFF position before attaching power cables.

| Warning: Remove jewelry (including rings, necklaces, and watches) before working on equipment that is connected to power lines. Metal objects heat up when connected to power and ground and can cause serious burns or become welded to the terminals.

| Warning: Do not insert any metal object, such as a screwdriver, into an open slot or the midplane. Doing so can cause electric shock and serious burns.

| Warning: Never attempt to repair parts of modules yourself. Only trained customer service personnel are authorized to service parts. Call Juniper Networks Customer Service to make arrangements to return defective modules for repair.