Ground Fixed

G1

Equipment protected from the weather and high levels of humidity, vibration, shock and excessive temperature variations. Maintained by military personnel.

Ground

Mobile

G2

Conditions more severe than conditions G1, mostly due to

vibration and shock. Cooling air may also be more limited and maintenance less uniform.

Ship

Protected

S1

Equipment protected from rain, high humidity levels and

excessive temperature variations. Subjected to the vibra- tion and shock levels relative to the main region of a ship.

Ship Exposed

S2

Conditions more severe than condition S1, mostly due to

the increased vibration and shock levels associated with the bows, aft and masthead regions of a ship.

Air Protected

A1

Equipment situated in typical cockpit conditions and

protected from the environmental extremes of pressure, temperature, shock and vibration.

Air Exposed

A2

Equipment bay, tail, nose or wing installations with envi-

ronmental extremes of pressure, temperature, shock and vibration.