This report was prepared by A.R.F. Products, Inc., Raton, New Mexico, under contract H0308004. The contract was initiated under the Mine Health and Safety Program. It was administered under the technical direction of the Pittsburgh Research Center with Mr. Harry Dobroski acting as the Technical Project Officer. Mr.Patrick Neary was the Contract Administrator for the Bureau of Mines. This report is a summary of work recently completed as part of the contract during the period January 1980 through January 1983. This report was submitted by the author on 24 January 1983.

National Institute for Occupational Safety and Health