Research Contracts

New Search

Project at a Glance

Project Status: complete

Report Published June 1989:

Title: Investigation of the effects of acid deposition on materials

Principal Investigator / Author(s): Vijaykumar, R.

Contractor: Custom Engineering Environmental's Environmental Monitoring & Services, Inc and University of Southern California

Contract Number: A4-110-32 & A5-137-32

Topic Areas: Acid Deposition


Damage functions have been obtained for materials of economic significance which had been exposed between March 1986 and March 1988 at three sites in Southern California (Burbank, Long Beach and Upland), and a background site in Central California (Salinas). These damage functions relate the atmospheric corrosion loss to the concentration of routinely measured pollutants. The materials exposed were galvanized steel, nickel, two types of flat latex exterior house paint, aluminum, nylon fabric, polyethylene and concrete. Due to experimental problems with the concrete bricks and difficulties in determining corrosion damage for the polyethylene, damage functions are not available for these materials.

The exposure tests have been supported by laboratory experiments in which corrosion damage has been determined under carefully controlled conditions for single pollutants such as SOZ' N02 and į3' and their combinations, and for HN03 aerosol. SignifIcant damage was observed only in the presence of S02 or the HN03 aerosol.

At both the field and the laboratory tests atmospheric corrosion rate monitors (ACRM) have been exposed to provide a continuous record of the corrosion behavior. The ACRM data confirmed the results from the field tests that corrosion rates at the sites in Southern California were higher in the summer months than in the winter months. Statistical analysis of these data has shown that this behavior, which is different from that observed in most other exposure studies performed in Europe and elsewhere, is probably due to the very low S02 concentrations and the formation of gaseous HN01 as well as nitrate and sulfate particulates in the summer by photochemical reactions.


For questions regarding this research project, including available data and progress status, contact: Research Division staff at (916) 445-0753

Stay involved, sign up with CARB's Research Email Distribution List