Juniper MX960 Hardware Manual page 470

WARNING:
you slide the fan module out of the chassis. The fans might still be spinning.
5. Pause for approximately 15 seconds to allow the fans to stop spinning.
6. When the fans stop spinning, press on the two latches located on the inside of the fan tray.
7. Place one hand under the fan tray to support it, and pull the fan tray completely out of the chassis.
Figure 173: Removing an Upper Fan Tray
To avoid injury, keep tools and your fingers away from the fans as
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