Agilent Technologies N8900 series Operating Manual page 25

Before Installation or Use
Provide Adequate Air Flow
Do not block the air intake at the front, or the exhaust at the rear of the unit.
Fans cool the power supply by drawing air through the front and exhausting it out the back. Allows at least 8 inches (20
cm) of space at the front and back of the unit for adequate air circulation.
24 Agilent N8900 Series Operating and Service Guide