3
Substance
Concentration limit (particles/m
3
)
Dust particle diameter ≥ 5 µm
To eliminate corrosion and premature aging of components, the equipment room must also meet
limits on salts, acids, and sulfides, as shown in
Table1-3 Harmful gas limits in an equipment room
Gas
Max. (mg/m
3
)
SO
2
0.2
H
2
S
0.006
NH
3
0.05
Cl
2
0.01
NO
2
0.04
Cooling
The device draws in cool air from three sides: left, front, and rear and exhausts hot air from the right
side. For adequate heat dissipation of the device, follow these guidelines:
•
Plan the installation site for the device based on the airflow direction
•
Reserve a minimum clearance of 100 mm (3.94 in) around the air vents.
•
Make sure the rack or workbench has a good ventilation system.
Figure1-1 Heat dissipation
ESD prevention
On the communication network, ESD comes from the following sources:
•
External electric field such as outdoor high-voltage power lines and thunder and lightning.
•
Indoor environment, floor materials, device materials, and device components.
To prevent electrostatic discharge (ESD), follow these guidelines:
•
Ground the device reliably.
•
Take dust-proof measures for the equipment room. For more information, see "
•
Maintain the humidity and temperature at acceptable levels. For more information, see
"