Standard Practice for Operating Enclosed Carbon Arc Light Apparatus for Exposure of Nonmetallic Materials

The Scope

Real-Time Environmental Exposure Testing
Although accelerated testing cycles are an excellent scientific process to predict the performance of a coating system over time, nothing compares to real-time exposure in a harsh environment to test the ability of a coating to protect steel and other metals.

Tested according to the American Society for Testing Materials (ASTM) and United States Navy Specifications.

For this purpose, two independent laboratories were selected: Atlas Weathering Services Group and Q-Labs Weathering Research Center. Nine coated test panels and one uncoated control panel were placed on a 37 ½ degree solar tracking device at Atlas Weathering Services Group, near Phoenix, Arizona. Ten similar panels were placed at a 5 degree solar exposure, with a biweekly spray of water at Q-Labs Weathering Research Center, also near Phoenix, Arizona.

After one year of exposure, the panels were examined for signs of deterioration. Remarkably, the Rust Bullet panel, except for the scribe lines, shows virtually no difference between the panel that was routinely exposed to water and the panel which was not. As can be seen from the photos, most of the other panels show a significant difference between the results of exposure to a desert environment performed at Atlas, and the results of exposure to a desert environment with biweekly simulated rainfall performed at Q-Labs. Virtually any coating can do well in a desert environment, as shown in the Atlas photo; however, when a little water is added, as shown in the Q-Lab photo, the difference between Rust Bullet and its competitors is remarkable.