ANSI BHMA A156-18:1993 pdf download.American National Standard for materials and finishes
3.1.1 Surfaces on which a controlled deposit ordinarily cannot be obtained such as holes, recesses, bases of angles, and similar areas are exempt from the requirements for significant surfaces.
3.2 Salt Spray Test.
This test shall be conducted in accordance with ASTM B 117-90 Standard Method of Salt Spray (Fog) Testing.Parts shall withstand exposure for the time specified in the applicable ANSI/BHMA A156 Series Standard without corrosion exceeding one spot visible to the unaided eye per one square inch (25.4 square mm) of significant surface and without any spot larger than 1/16 in (1.6 mm)in diameter.
Corrosion is defined as a breakdown of the base material and is not be confused with surface staining. Corrosion of brass and bronze base material is green.Corrosion of steel base material is red rust having a reddish brown appearance. Corrosion of aluminum and zinc die cast base material is white.
3.2.1 When trim parts are reinforced with a dissimilar material and corrosion on the significant surface occurs as a result of the breakdown of the reinforcing, the corrosion shall be disregarded. Reinforcing material shall,however, withstand a salt spray test as described in 3.2 as specified the applicable ANSI/BHMA A156 Series Standard.
3.2.1 When trim parts are reinforced with a dissimilar material and corrosion on the significant surface occurs as a result of the breakdown of the reinforcing, the corrosion shall be disregarded. Reinforcing material shall,however, withstand a salt spray test as described in 3.2 as specified in the applicable ANSI/BHMA A156 Series Standard.
3.3 Humidity Test.
This test shall be conducted in a chamber having a 95%土5% relative humidity at 100 degrees F±5 degrees (38 degrees C±3 degrees) for the times specified in the applicable ANSI/BHMA A156 Series Standard. The parts shall be allowed to stabilize at room temperature for 30 minutes before they are examined. The coating shall then meet a pencil hardness test (see 3.4) as specified in the applicable ANSI/BHMA A156 Series Standard.
Blistering of the organic coating or tarnishing of the part shall not be visible to the unaided eye.Parts shall also meet the method B Cross-Cut Tape Test as defined in ASTM D 3359-90 Method for Measuring Adhesion by Tape Test after the humidity exposure and 30 minute stabilization time. The rating shall be as specified in the applicable ANSI/BHMA A156 Series Standard.ANSI BHMA A156-18 pdf download.