FTM 5329 (FED-STD-791 Method 5329) Corrosion Protection (Humidity Cabinet)
Metals may be weakened or destroyed when they react with atmospheric oxygen to produce rust. The reaction rate is increased by the presence of liquid or atmospheric water. This test measures the ability of oils containing metal preservatives to inhibit rust formation in high humidity atmospheres.
Steel panels are sand blasted, cleaned and dipped in the sample oil. They are then hung in a controlled-temperature, controlled-humidity chamber for the specified test time. Panels are removed and rust formation is evaluated. The report lists the number of rust spots less than 0.1 cm, 0.1cm to 0.2cm and greater than 0.2cm. This test can be run for a specified period of time or ""until failure” – until rust forms.