OSHA 30 Construction Excavations Part 1,2,3 Flashcards
what is a trench
a hole that is deeper then it is wide
what are the OSHA requirements for trenches supports
the trench must be 5 feet deep and their must be reasonable evidence that their is a cave-in possible
OSHA requires air monitoring in trenches deeper
4 feet
can you tell a ground is type A soil type by look
no
what are characterisitcs in a cavein in
lateral PRESSURE up to 800LBS
Cubic yard weight can be 3000lbs
how far away can spoil pile be
2 feet from side of trench
what are the 4 classification soil
solid rock
type A
Type B
Type C
what are common soil tests
ribbon
thread
thumb
dry strength
sedimentation
type B soil is not
sand
when are protective systems not needed
when working with solid rock
when dealing with trenches 5 feet or less and without sign of possible cave-ins
type A protective systems
sloping 3/4 of an inch every 1 foot
type B protective systems
having slopping at 45 degrees or 1 foot per 1 foot of trench wall
why type c soil not practicel
it is a poor conditions for it
what must be done if type C soil is sloped
it needs to be 1.5 per 1 foot of trench
should trenches that are supported by aluminum shoring be allowed to be entered after they are placed
no`
how far away should the shoring of the hydraulic shores be
they should e be 4 feet max away from each other and the lowest cylinders should be two feet min from the ground
most shores are pumped up to
1000lbs and imparts 3000psi
what needed for workers to work in a type C -type soil
whalers
type B soil allows for how many options of protection
4
what type of soil is the most common
type B
mixed oak timber have greater bending strength then Douglas fir per square inch
false
were are the systems for working workers placed in
in section E 1926
What are screw jack systems
they are like hydraulics but must be adjusted manually
When must an engineer be involved in shoring techniques
when the excavation is deep the 20 feet
how far away must equipment be from power sources
10 feet
what zone but all equipment be operated in
the zone full operation
were can the osha excavation standard be found
29CFR excavation standard
what is the requirement of a competent worker
someone who know
General protection requirements
Soil classifications
protective systems