2Symbol DescriptionTransported and stored avoiding humidity, rains and wet floor.Electrical safety• Carefully examine your work area for possible hazards such as moist floors, ungrounded powerextension cables, and missing safety grounds.• Locate the emergency power-off switch in the room before installation. Shut the power off atonce in case accident occurs.• Do not work alone when the firewall has power.• Always verify that the power has been disconnected.Laser safetyWARNING!Disconnected optical fibers or transceiver modules might emit invisible laser light. Do not stare intobeams or view directly with optical instruments when the switch is operating.The firewall is a Class 1 laser device.• Before you disconnect the fiber connector, execute the shutdown command in interface viewto disable the optical source.• Install dust caps to disconnected optical fiber connectors and ports on disconnected transceivermodules to avoid damage caused by built-up dust.• Insert a dust plug into empty fiber ports.Handling safetyWhen you move the firewall, follow these guidelines:• Move and unpack the firewall carefully to avoid firewall damage.• Unpack the firewall at least half an hour and power on the firewall at least two hours after youmove it from a place below 0°C (32°F) to the equipment room. This prevents condensation andeven damage to the firewall.• Use a safety hand truck when you move multiple firewalls.• Before you move the firewall, remove all cables and mounting brackets.• For long-distance transportation, remove all the field-replaceable units (FRUs), such as powermodules and interface modules, and package them separately, and install the filler panelssupplied with the firewall. For short-distance transportation, make sure all the FRUs aresecurely seated in the slots and the screws are fastened.• When you move or lift the firewall chassis, support the bottom of the chassis, rather thanholding any FRU.• Make sure the accessories of the firewall are not lost or damaged during firewall moving.