OSHA 30- Excavation Hazards, Soils
A cubic yard of soil can weigh as much as: - answer A small pickup truck
To be classified as type A, the soil cannot be - answer All of the above (disturbed, part
of a mixed layered system, subject to vibration, seeping water
When your trench is deeper than 4 ft and hazards may be present, air monitoring must
be done before entry - answer True
A soil cannot be Type A if it is: - answer All of the above
Which of the following are common soil classification tests? - answer All except C
A soils are usually clay and cemented soils such as caliche and hardpan - answer True
Each of the following is Type B soil EXCEPT: - answer Sand
The definition of type C-60 soil is provided by manufactures to allow the competent
person an opportunity to use vertical shores or other protective systems in accordance
with tables provided by the manufacture - answer True
The most important distinction b/w stable rock types A&B and type C is: -
answerDegree of stability
A defining feature of stable rock is that it will: - answerRemain intact while exposed
OSHA requires that the competent person perform two visual and two manual test on a
soil sample fresh out of the ground and not impacted by weather conditions at the site -
answerFalse
Aluminum hydraulic shoring permits both installation and removal without entering the
trench - answerTrue
Shores must be pumped to a minimum of 750 pounds of pressure but more is
recommended - answerTrue
Type B soils afford how many options of protection? - answerFour
Which soil type is the most common? - answerType B
Which of the following statements is true of kickout? - answerAll of the above
, Mixed oak timber have a greater bending strength per square inch than Douglas fir -
answerFalse
In type C soil, the angle of repose is very low, how many degrees must the angle be? -
answer34
The depth at which an excavation needs attention from a registered professional
engineer is: - answer20 ft
Placing a shield (e.g., trench shield or trench box) between the side of an excavation
and the work area can minimize the risk in the event of a cave in. - answerTrue
Shoring and shielding can be custom built from tabulated data approved by a registered
PE. - answerTrue
The struts of a screw jack system must be adjusted manually, which creates a hazard
because the worker is required to: - answerBe in the trench in order to adjust the strut
All systems have a set of manufacturer's tabulated data to be used for proper design
and installation of the equipment - answerTrue
When using a ladder in a trench, it must be: - answerAll of the above
A surface encumbrance is anything that could create a ___ in or around a trench. -
answerHazard
Walkways must have handrails when at __ or more above lower level - answer6 ft
A competent person must inspect all excavations, adjacent areas, and protective
systems daily, ____, and as needed throughout the shift. - answerBefore work begins
Establishing eye contact with your equipment operator is a general safety principle
when working outside the working radius. - answerTrue
Being dangerously close to a falling load is: - answerNot allowed
Each of the following is true of accumulating water hazards EXCEPT: - answerSpecial
supports or shield are not allowed.
Warning systems for mobile equipment include barricades, hand signals, stop logs -
answerTrue
All surface encumbrances must be removed or supported within: - answerThe zone of
influence
A cubic yard of soil can weigh as much as: - answer A small pickup truck
To be classified as type A, the soil cannot be - answer All of the above (disturbed, part
of a mixed layered system, subject to vibration, seeping water
When your trench is deeper than 4 ft and hazards may be present, air monitoring must
be done before entry - answer True
A soil cannot be Type A if it is: - answer All of the above
Which of the following are common soil classification tests? - answer All except C
A soils are usually clay and cemented soils such as caliche and hardpan - answer True
Each of the following is Type B soil EXCEPT: - answer Sand
The definition of type C-60 soil is provided by manufactures to allow the competent
person an opportunity to use vertical shores or other protective systems in accordance
with tables provided by the manufacture - answer True
The most important distinction b/w stable rock types A&B and type C is: -
answerDegree of stability
A defining feature of stable rock is that it will: - answerRemain intact while exposed
OSHA requires that the competent person perform two visual and two manual test on a
soil sample fresh out of the ground and not impacted by weather conditions at the site -
answerFalse
Aluminum hydraulic shoring permits both installation and removal without entering the
trench - answerTrue
Shores must be pumped to a minimum of 750 pounds of pressure but more is
recommended - answerTrue
Type B soils afford how many options of protection? - answerFour
Which soil type is the most common? - answerType B
Which of the following statements is true of kickout? - answerAll of the above
, Mixed oak timber have a greater bending strength per square inch than Douglas fir -
answerFalse
In type C soil, the angle of repose is very low, how many degrees must the angle be? -
answer34
The depth at which an excavation needs attention from a registered professional
engineer is: - answer20 ft
Placing a shield (e.g., trench shield or trench box) between the side of an excavation
and the work area can minimize the risk in the event of a cave in. - answerTrue
Shoring and shielding can be custom built from tabulated data approved by a registered
PE. - answerTrue
The struts of a screw jack system must be adjusted manually, which creates a hazard
because the worker is required to: - answerBe in the trench in order to adjust the strut
All systems have a set of manufacturer's tabulated data to be used for proper design
and installation of the equipment - answerTrue
When using a ladder in a trench, it must be: - answerAll of the above
A surface encumbrance is anything that could create a ___ in or around a trench. -
answerHazard
Walkways must have handrails when at __ or more above lower level - answer6 ft
A competent person must inspect all excavations, adjacent areas, and protective
systems daily, ____, and as needed throughout the shift. - answerBefore work begins
Establishing eye contact with your equipment operator is a general safety principle
when working outside the working radius. - answerTrue
Being dangerously close to a falling load is: - answerNot allowed
Each of the following is true of accumulating water hazards EXCEPT: - answerSpecial
supports or shield are not allowed.
Warning systems for mobile equipment include barricades, hand signals, stop logs -
answerTrue
All surface encumbrances must be removed or supported within: - answerThe zone of
influence
