Update : Roof Monitoring Safety System for underground stone mines.

Bibliographic Details
Corporate Author:	Pittsburgh Research Laboratory (National Institute for Occupational Safety and Health)
Format:	Government Document Book
Language:	English
Published:	[Pittsburgh, Pa.] : U.S. Dept. of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, [2000]
Series:	Technology news ; no. 481.
Subjects:	Mine roof control > United States > Equipment and supplies.
Online Access:	https://purl.fdlp.gov/GPO/LPS92007