Cisco Catalyst 9400 Series

Figure 25: NEBS-Compliant Air Filter
We recommend that you change the air filter every 3 months. However, examine the air filter once
a month (or more often in dusty environments) and replace it if it appears to be excessively dirty
or damaged. To comply with Telecordia GR-63-Core standard air filter requirements for NEBS
deployments, the air filter must be replaced, not cleaned.
Note
Step 7 Install the top and base covers as shown in illustrations:
Cisco Catalyst 9400 Series Switches Hardware Installation Guide
77
Installing the Switch
Rack-Mounting the Chassis in a NEBS-Compliant Mode