Trench Excavation Factsheet (PDF)
OSHA's safety and health topic on Trenching and Excavation
FY 14 fatalities and casualties report.
Worker Fatalities Reported to Federal and State OSHA
U.S. Department of Labor -- About DOL -- Important Web Site Notices Rules and Guidelines for linking to OSHA – OSHA and DOL are considered public domain
CDC - Trenching and Excavation - NIOSH Workplace Safety and Health Topic - to find statistics, topics, trainings etc. on the National institute of safety and health website
Bureau of Labor and statistics - Census of Fatal Occupational Injuries (CFOI) - Current and Revised Data