Keywords: Trench safety - hardware rigging attached to backhoe (9247879269).jpg hardware rigging attached to a backhoe https //www flickr com/photos/niosh/9247879269/ Trench safety - hardware rigging attached to backhoe 2010-03-17 11 38 https //www flickr com/people/25069384 N03 National Institute for Occupational Safety and Health NIOSH from USA PD-USGov NIOSH http //flickr com/photos/25069384 N03/9247879269 2015-04-23 18 51 23 United States Government Work Construction Safety Shoring Work Workplace National Institute for Occupational Safety and Health |