EXFO FTB-2 - Manual (Page 263)

FTB-2 and FTB-2 Pro 253
13 Maintenance
To help ensure long, trouble-free operation:

Always inspect fiber-optic connectors before using them and clean
them if necessary.

Keep the unit free of dust.

Clean the unit casing and front panel with a cloth slightly dampened
with water.

Store unit at room temperature in a clean and dry area. Keep the unit
out of direct sunlight.

Avoid high humidity or significant temperature fluctuations.

Avoid unnecessary shocks and vibrations.

If any liquids are spilled on or into the unit, turn off the power
immediately, disconnect from any external power source, remove the
batteries and let the unit dry completely.
W
ARNING
The use of controls, adjustments and procedures, namely for
operation and maintenance, other than those specified herein may
result in hazardous radiation exposure or impair the protection
provided by this unit.