Materials degradation in the atmosphere.

Most man-made materials deteriorate upon exposure to the atmosphere. The diversity of materials and atmospheric constituents renders it difficult to specify many of the mechanisms of deterioration, but the potential for deterioration is of substantial interest in any case. We assemble here the available information on the sensitivities of common materials to various atmospheric species. Then, using newly devised display techniques, we combine this information with atmospheric chemical analyses to assess the materials degradation potential of the atmospheric gas, airborne particles, dew, fog, rain, snow, and indoor air. The results suggest that materials degradation due to dissolved sulfur gases may occur largely in dew and fog, that degradation by ammonium ion in fog and in deposited particles can be significant, and that formaldehyde and organic acids have the potential to degrade several metals, particularly zinc.