MIOSHA: Summary: Part 9 Excavation, Trenching, and Shoring Flashcards
- “Soil” means any of the following:
a. “Clay”–
a very fine textured soil that derives its resistance to displacement from cohesion and may be:
- “Soil” means any of the following:
“Soft clay”–
a clay-type soil that has an unconfined strength of less than 1.0 ton per square foot.
- “Soil” means any of the following:
“Medium clay,”
sometimes called plastic–a clay-type soil that has a minimum unconfined strength of 1.0 ton per square foot.
- “Soil” means any of the following:
“Firm soil”–
a clay-type soil that is resistant to forces causing rupture or displacement. A firm clay has a minimum unconfined strength of 1.5 tons_ per square foot.
- “Soil” means any of the following:
“Stiff clay”–
a clay-type soil that is very resistant to forces causing rupture or displacement. A stiff clay has a minimum unconfined strength of 2.5 tons_ per square foot.
- “Soil” means any of the following:
“Fill”–
a manmade soil condition that may be constructed of any type of soil or combination thereof.
- “Soil” means any of the following:
“Granular soil”–
a coarse grained soil that does not possess cohesion but derives its strength from internal friction.
- “Soil” means any of the following:
Organic soil”–
a soil that contains significant amounts of peat, muck, or marl.
- “Soil” means any of the following:
“Running soil”–
any type of soil that has insufficient strength to stand unsupported. Running soil tends to run or slough into the excavation as the excavation is being dug.
- “Soil” means any of the following:
Toe of slope” means
the point at which the side of an
excavation intersects the lowest level of the excavation
B. Locating utility lines
An employer shall not excavate in a street, highway, public place, a private easement of a public utility, or near the location of a public utility facility owned, maintained, or installed on a customer’s premises, without X
having first ascertained the location of all underground facilities of a public utility in the
proposed area of excavation
B. Locating utility lines
Upon receiving X, an
employer shall exercise reasonable care when working in close proximity to the underground facilities of any public utility. If the facilities are to be exposed, or are likely to be exposed; only X shall be employed in such circumstances.
the information from the public utility
hand digging
C. Excavation; consideration of soil types; water; slide
hazards:
If different textured soils are encountered in the side of an excavation, each X, except that the slope shall not Y
soil type of the excavation shall be cut to the proper angle of repose
steepen between the toe of the slope and the ground level where soft clay or running soil is encountered in the lower cut.
C. Excavation; consideration of soil types; water; slide
hazards:
If the excavation is a trench, a X shall be used or the sides shall be properly sloped to protect against a cave-in.
trench shoring system
C. Excavation; consideration of soil types; water; slide
hazards:
An employee shall not work in an excavation in which there is accumulated water or in which water is accumulating unless X. The X adequately vary with each situation, but may include special support or shield systems to protect from cave-ins, water removal to control the level of accumulating water, or the use of a safety harness and lifeline.
precautions have been taken to protect employees against the hazards posed by water accumulation
C. Excavation; consideration of soil types; water; slide
hazards:
If water is controlled or prevented from accumulating by the use of water removal equipment, the water removal
equipment and operation shall be X
monitored by a qualified employee to ensure that the equipment is properly operated.
C. Excavation; consideration of soil types; water; slide
hazards:
An ongoing X of an excavation or trench shall
be made by a qualified person. After every Y, an inspection shall be made by a qualified employee for evidence of possible slides or cave-ins. Where these conditions are found, all work shall Z
inspection
rainstorm or other hazard-producing occurrence
cease until additional precautions, such as additional shoring or reducing the slope, have been accomplished.
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
A tree, boulder, rock fragments, or other obstructions whose movement could cause injury to an employee shall be X
removed or supported.
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
An excavation that an employee is required to enter shall have excavated and other material stored and retained not less than X feet from the excavation edge.
2
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
When a shoring system is used, the system shall be designed and used to X when heavy equipment, material handling equipment, or material is located near an excavation.
resist the added pressure
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
When mobile equipment is utilized or permitted adjacent to an excavation where the operator’s vision is restricted, X shall be utilized or a signal person shall be used.
stop logs or barricades
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
An excavation X or more inches in depth and occupied
by an employee shall be provided with either a ladder
extending not less than Y feet above the top as a
means of access or with a ramp meeting the requirements of subrule (6) of this rule. Lateral travel along the wall of a trench to a ladder or other means of egress shall not exceed Z feet.
48
3
25
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
An earth ramp may be used in place of a ladder if it meets all of the following requirements:
a. The ramp material shall be X.
stable
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
An earth ramp may be used in place of a ladder if it meets all of the following requirements:
b. The sides of the excavation above the ramp shall be
X or sheeted or Y
maintained to the angle of repose
shored along the means of egress.
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
An earth ramp may be used in place of a ladder if it meets all of the following requirements:
c. The degree of angle of the ramp shall not be more than X
45 degrees.
D. Excavation; obstructions; retaining materials; egress;
guarding; heavy equipment
An earth ramp may be used in place of a ladder if it meets all of the following requirements:
d. Vertical height between the floor of the trench and the toe of the ramp shall not exceed X inches
30
E. Excavation; angle of repose
- The side of an excavation more than X feet deep shall
be Y as prescribed in table 1, unless supported as
prescribed in this part.
5
sloped
E. Excavation; angle of repose
- An excavation less than X feet in depth shall also be
Y when examination of the ground indicates hazardous earth movement may be expected.
5
effectively protected
E. Excavation; angle of repose
- If 1 side of a trench is X feet or less in depth and the other side is deeper than X feet, the side Y shall be protected as provided in this part. All excavated material shall be placed on the low side if possible.
5
5
deeper than 5 feet
E. Excavation; angle of repose
Special attention shall be given to a side that X
may be
adversely affected by weather or moisture content.
F. Supporting systems; angle of repose; tie backs;
tight sheeting; additional bracing
The angle of repose and the design of the supporting
system for a side of an excavation shall be based on the
valuation of all of the following factors:
Depth of cut and type of soil:
a. Possible variation in the X of the material
while the excavation is open
water content
F. Supporting systems; angle of repose; tie backs;
tight sheeting; additional bracing
The angle of repose and the design of the supporting
system for a side of an excavation shall be based on the
valuation of all of the following factors:
Depth of cut and type of soil:
b. Anticipated changes in the material due to X
exposure to air, sun, water, or freezing
F. Supporting systems; angle of repose; tie backs;
tight sheeting; additional bracing
The angle of repose and the design of the supporting
system for a side of an excavation shall be based on the
valuation of all of the following factors:
Depth of cut and type of soil:
c. Load imposed by X
structures, equipment, overlying
material, or stored material
F. Supporting systems; angle of repose; tie backs;
tight sheeting; additional bracing
The angle of repose and the design of the supporting
system for a side of an excavation shall be based on the
valuation of all of the following factors:
Depth of cut and type of soil:
e. Vibration from X
traffic, equipment, or blasting.
F. Supporting systems; angle of repose; tie backs;
tight sheeting; additional bracing
- A support system shall be designed by X. The design of the supporting system shall be maintained at Y. Changes from the design of the support system shall be approved by X
a qualified employee
the jobsite
a qualified employee.
Utility locates marked in orange are ____________.
communication fiber optics
As a general rule, utility locates may be within _____ variance.
a 18-in
_________ is hand digging in compacted soils to expose underground pipe and lines.
potholing
