Term
| high-pressure air bags in a trench collapse situation. The lifting operation must be closely monitored and stopped if there |
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Definition
| is any indication of instability. |
|
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Term
| No more than bags should be stacked on each other. |
|
Definition
|
|
Term
| The maximum lifting capacity of the stacked bags is based on the rated capacity of the , which should be placed on top of the stack. |
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Definition
|
|
Term
| When using two bags side by side or at two points on a load, the maximum load capacity is based on |
|
Definition
| adding the rated capacity of both bags together. |
|
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Term
| Cribbing: With the load resting on two contact points of each crib box, keep the height to width ratio to |
|
Definition
|
|
Term
| various cribbing types include |
|
Definition
| the Box Crib (2x2 Crib), Crosstie Crib (3x3 Crib), and Solid Crib (entire surface area contact). |
|
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Term
| stabilize the working area of the lip of the trench using on the non-spoil pile side |
|
Definition
| 4’x8’x5/8” sheets of plywood (planking) |
|
|
Term
| stabilize the working area of the lip of the trench using on the spoil pile side |
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Definition
| 2”x 12”- 12’ boards for the spoil pile side. |
|
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Term
| Anywhere the trench end is less than 4’ wide it can be made safe by |
|
Definition
| using the 2”x 12” x 12’ boards. If greater than 4’ it should be treated as a face or wall. |
|
|
Term
| the collapse zone within the trench is equal to |
|
Definition
| 1½ times the vertical depth of the trench |
|
|
Term
For a non-intersecting trench
a minimum of panels... |
|
Definition
| 6 panels will be needed (3 on each side) to provide a minimum safe horizontal work area for rescuers of 12 feet. |
|
|
Term
| As a means of entry and egress a stairway, ladder, ramp or other means of safe egress must be installed in trenches with a depth of |
|
Definition
| 4 feet or greater, (OSHA CFR 1926.651 (c)(2). |
|
|
Term
| Horizontal spacing of ladders/ramps shall be no more than |
|
Definition
| 25 feet, (OSHA CFR 1926.651 (c) (2). |
|
|
Term
i) For rescue operations a minimum of
ladders are recommended to be installed in close proximity to the interior rescue personnel. |
|
Definition
|
|
Term
| If a person is within the collapse zone of an exposed end wall, |
|
Definition
| the end wall must be shored. |
|
|
Term
| Screw jacks are good for spanning horizontal distances of |
|
Definition
| 5-7 feet depending on the specific manufacturer. |
|
|
Term
| Cheater bars are to use on screw jacks when tightening. |
|
Definition
|
|
Term
| The minimum acceptable dimension for a timber shore in Type C soil will vary from |
|
Definition
a 6”x8” to an 8”x10” for depths up to
20 feet |
|
|
Term
| The timber shore in Type C soil will have a maximum allowable vertical spacing |
|
Definition
|
|
Term
| timber shore in Type C soil will vary for depths up to |
|
Definition
|
|
Term
general guidelines for installing various types of shoring devices.
a) The first installed shore should be no lower than |
|
Definition
|
|
Term
general guidelines for installing various types of shoring devices.
the last installed shore should be no higher than |
|
Definition
| 24 inches from the bottom of the trench |
|
|
Term
| The first pneumatic shore to shoot is the |
|
Definition
|
|
Term
| pneumatic shores should be shot in the order of |
|
Definition
|
|
Term
e) If a rescuer must enter the trench to assist with placing the ____
pneumatic shore then the
order should be ____ |
|
Definition
| bottom / middle, top, bottom |
|
|
Term
| The order walers are placed (not shot) in a trench is |
|
Definition
|
|
Term
| The lower walers are not set in a trench until |
|
Definition
|
|
Term
|
Definition
| wider horizontal shoring space and work area. |
|
|
Term
| To shore a deep trench with 3 panels, |
|
Definition
| set the bottom two upright, and the third horizontally above them. |
|
|
Term
| Supplemental shoring is required when a void is created extending ___ feet below the bottom of the protective system. |
|
Definition
|
|
Term
| supplemental shoring consist of |
|
Definition
| 2 to 4 2 ”x 12 ”x 12 foot long strongbacks placed horizontally behind the bottom of the vertical strong back of each panel and to the same configuration on the opposite wall. |
|
|
Term
| When constructing a Waler type protective system, supplemental shoring can be |
|
Definition
| sheets of plywood (1 1/8”), Shoreform (minimum 1”) or additional 2”x12” strongbacks can be lowered between the strongbacks attached to the panel as need and shimmed in placed until they need to be lowered again. |
|
|
Term
|
Definition
| the angle trench walls should be cut back to reduce the chance of workers becoming buried in a collapse. The recommended angle is 34 degrees or for every foot of vertical depth the trench should be cut back horizontally 1 ½ times the vertical depth. |
|
|
Term
|
Definition
soil that is in a condition where a cave-in is imminent. Signs include
fissures around the lip of the trench, or on the trench wall, bulging of the trench wall, or running water in the trench. |
|
|
Term
|
Definition
| any man made cut, cavity, trench or depression into the earth surface created by earth removal. |
|
|
Term
| When using a combination of pickets, they should be lashed together with a _ rope. |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| minimum 2' by 3/8" diameter |
|
|
Term
| Start lashing on a timber A frame at ___ and go ___ |
|
Definition
|
|
Term
| lashing a gin pole, use a __ rope |
|
Definition
|
|
Term
| For the base of the gin pole, dig a hole |
|
Definition
| 6” to 12” deep, depending on the soil |
|
|
Term
| ___ can be used to probe in loose dirt |
|
Definition
|
|
Term
| the operation has been determined to be recovery, consideration may be given to cutting the trench walls back. ____may not permit this. |
|
Definition
| Allowable space and obstacles. |
|
|
Term
| Identify the rules for digging in a trench. |
|
Definition
c) Dig by hand when you get near the victim.
b) Make sure that all of the victim’s body parts are well protected. |
|
|
Term
| Rope grab devices with teeth |
|
Definition
| should not be used in hauling systems involving humans. |
|
|
Term
| Rope grab devices with teeth |
|
Definition
| should not be used in hauling systems involving humans. |
|
|
Term
| The rope grab device should be |
|
Definition
| rated for the load: light duty, or general duty. |
|
|
Term
| prussik hitches, also referred to as |
|
Definition
|
|
Term
For rescue operations prussik hitches, also referred to as
friction hitches, are usually used in |
|
Definition
|
|
Term
| a braking prussik hitch can be |
|
Definition
| tandem prussik hitches or rope grab devices rated for the load. |
|
|
Term
|
Definition
| can be used in the switching over from a raising system to a lowering system and vice versa. |
|
|
Term
|
Definition
| soil that does not exhibit visible signs of moisture content. |
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