Earthmoving/ trenching construction, safety: Caterpillar 320CL track mounted hydraulic excavator/backhoe excavates a bucket of soil inside trench shield/box. Trench shield extends from bottom of trench to above top of excavation and protects the workers inside it from possible trench wall cavein. Backhoe bucket is sized to fit interior width of shield. Primary excation was by this same backhoe using a wider, larger bucket. First Street, Ann Arbor, Michigan 2006.

Earthmoving/ trenching construction, safety: Caterpillar 320CL track mounted hydraulic excavator/backhoe excavates a bucket of soil inside trench shield/box. Trench shield extends from bottom of trench to above top of excavation and protects the workers inside it from possible trench wall cavein. Backhoe bucket is sized to fit interior width of shield. Primary excation was by this same backhoe using a wider, larger bucket. First Street, Ann Arbor, Michigan 2006.