There are several categories of equipments used in determining shelf life for avionics. Shelf life refers to the amount of time that an avionics unit can remain in storage and still be expected to perform to specifications. Shelf life suggestions assume that a unit is controlled and maintained in environment where humidity is less than 60%, temperature is 68 deg. F +- 10, and in the absence of noncorrosive contaminants.

The categories are based on equipment intricacy, type and quantity of mechanical parts, and other factors such as lubrication, etc.

According to the Rockwell Collins Instruction Book for Avionics Standard Shop Practices, the longest shelf life period should be 5 years. This pertains to the least complex equipment such as mounts that only require visual inspection after 5 years to recertify.

For other, more complex equipment the following shelf life guidelines should be followed:
 

Most avionics manufacturers advise that units should be recertified per performance tests in the applicable manual by the end of the shelf life period.