PURPOSE: To specify the type, concentration and relative humidity of a corrosive gas in an enviroment in a short time without requiring a specialist for analysis concerning an evaluation method of the setting of electric and electronic equipment and parts composing them and preserving environment thereof.

CONSTITUTION: The apparance of a plurality of metal test pieces 4 for comparison which are produced by leaving multiple kinds of metal pieces alone separately in a plurality of environments for which the type, concentration and relative humidity of a corrosive gas such as sulfur dioxide, hydrogen sulfide or chlorine are set respectively beforehand and test pieces which is made of the same metal as the metal test pieces for comparison which are left alone in an environment where electric and electronic equipment are set and preserved for a fixed time is compared mutually. Thus, the type, concentration and relative humidity of the corrosive gas are specified in the environment of setting and preserving the electric and electronic equipment.