Soil weighs ___ to ___ lbs per cubic foot
100 to 125lbs
A victim with a foot or two of soil on them could be receiving?
750 to 1000lbs of pressure on their chest
C 60 will
Stand long enough to install shoring and have a water level at or below the bottom of the excavation
Type C soil is considered to be the
Least stable
All soil should be treated as
Type C soil
Control zones are how far in distance
50, 150, 300ft
Evacuation signal is 10 seconds followed by a
10 second pause
When approaching the trench, how far should you keep from the edge?
2-3ft
A ladder/means of egress shall be placed in a trench that is
4ft deep or more
The ladder must extend
3ft above grade