Book Description

Volume 1 documents the methodology, developments, and findings of the two-year study. Among the significant results of this project are: (1) a new set of crossing signal visibility specifications based on widely accepted definitions of motorists' requirements and a demonstration that currently available signals exceed these specifications when properly maintained; (2) the evaluation of seven alterations to standard crossing signal design and operation with respect to performance improvement and maintenance requirements--several of these modifications offer attractive cost/benefit attributes and are recommended for implementation; and (3) the development and evaluation of three tools of potential value to signal maintenance crews: an alignment scope to aid in aiming of the signal for maximum effectiveness, a signal focusing tool to aid in the critical positioning of the signal lamp with respect to the reflector, and a signal flux meter for measuring the light output of crossing and traffic signals--all of these tools were proven effective and would be useful to a conscientious maintenance team. The prototype signal hardware underwent rigorous laboratory, environmental, and field tests. The maintenance tools were evaluated under laboratory conditions. Vol. III is intended to ba a stand-alone handbook for potential users of the project's developments.