Trench Rescue(Definitions) Flashcards
active soil
soil that has the ability to contain potential
energy
air knife
pneumatic tool used to cut away dirt using
a high velocity jet of air
angle of repose
angle at which loose particulate products
will support their own weight.
stable position shows that ____ has less
effect on the soil/product than the _____
gravity
natural cohesion of the soil/product
trenches have the same 8 hazardous
atmospheres as CS
oxygen enrichment oxygen deficiency flammable vapors toxic vapors flammable vapors within 10% of LEL substance concentrations that exceed PELs airborne combustible dust at it's LEL particles of combustion
if trenches are _____, then they need to
be air tested. they are tested for 3 things.
4’ deep or deeper
oxygen saturation
flammability (gases must be < 10% LEL)
toxicity (gases must be < their toxic levels)
air testing priority is _____ as CS
the same
authorized entrants for Trench Rescue
must be able to do 8 things
use proper PPEs safely enter and work in the space use proper equipment ID and alert attendant for hazards provide status updates monitor for evacuation alert attach safety line to victim perform self-rescue
backfill
the material used to refill a trench
backfilling
refilling the trench
batter boards
series of horizontal boards spanning a
trench that are used to set the line and
grade of a pipe
bedding
fine stone or sand placed in the bottom of
the trench to be the foundation for pipes
bell pier
when the footing excavation or shaft has
a larger cross-section on the bottom than
the top
if a bell pier condition is created by ____
than you have an extreme potential for
_____.
water
collapse
benching
cutting walls of a trench so that steps
are formed
