Method 509.7 is the Salt Fog test from MIL-STD-810H. It is performed to determine the effectiveness of protective coatings and finishes on materials and may also be applied to determine the effects of salt deposits on the physical and electrical aspects of materiel.
The method is used for screening purposes only to evaluate the effectiveness and quality of protective coatings and finishes on materiel and material coupons, and to locate potential problem areas, quality control deficiencies, and design flaws in a relatively short period of time.
Although not representative of the natural environment, this test indicates potential problem areas associated with the salt (marine) environment. It should only be applied to materiel that will experience significant exposure to high levels of salt in the atmosphere.
Method 4.7.15 is a salt fog test for carbon-based conductive fibers. Three samples of size 26 uninsulated conductor, each approximately 3 feet (0.91 m) in length, are placed on PTFE or PTFE-coated mandrels that are 6 times the diameter of the wire with the ends secured.
Lead wires are attached to each end of the test sample and DC resistance is measured through the lead wires. The three samples are then hung in a chamber and exposed to the salt fog environment.
After exposure, DC resistance is measured again and compared to pre-test values. This test evaluates the corrosion resistance of carbon-based conductive fiber conductors in marine salt-laden atmospheres.