NJ DOT – the mathis bridge study

Prepared by Fred Lovett, Principal Engineer,
Matt Dorner, Assistant Engineer,
John Shaner, Technician II

This study is a continuing evaluation of the "in field" performance of various structural coatings that were originally evaluated in order to select a replacement coating system for the (Lead Paint), Basic Lead Silico Chromate (BLSC) alkyd paint system, specified by the Department prior to 1989.

This 1994 evaluation did not include a life cycle cost analysis, however based on the performance ratings, the following conclusions are made:

• The zinc metalizing systems (100% solids, no VOCs) are out performing all other generic systems.
• Zinc rich primers (inorganic and organic) continue as the best performing primers.

In 1990, environmental regulations were revised limiting architectural coatings to a maximum 3.8 lbs. pr gal. VOC (volatile organic compounds). However, metallic primers (i.e. zinc primers) have a limit of 4.2 lbs. per gal. VOC. Therefore, most of the coatings included in this study fail to meet current VOC regulations. Many of the inorganic zinc primers, most of the urethane and all of the vinyls, as manufactured for study, are now obsolete.

FULL DETAILS CAN BE FOUND AT: http://www.tfhrc.gov/hnr20/bridge/metal.htm