Anchors

Question 1

What is the role of an anchor in vertical rescue?

Answer 1

Stops the rope system and everything attached to it from hitting the ground

Anchors provide a stable and secure platform to lower or raise persons to a safe location.

Question 2

What are the three categories of anchors?

Answer 2

• Structural
• Natural
• Constructed

Question 3

What are examples of structural anchors?

Answer 3

• Beams
• Posts
• Handrails
• Walls
• Rings
• Bolts

Question 4

What must be ensured when using structural anchors?

Answer 4

That they are bomber for the task and the supporting structures

Ensure concrete, nuts, and bolts are fit for purpose.

Question 5

What types of anchors are classified as natural anchors?

Answer 5

• Trees
• Large rocks
• Boulders

Question 6

What factors must be considered for natural anchors?

Answer 6

Soil securing the tree, health of the tree, root system, and condition of rocks

Detached or fractured rocks are likely not fit for purpose.

Question 7

What are constructed anchors commonly made from?

Answer 7

Vehicles

Use designed anchor points on vehicles or properly secured structures.

Question 8

What acronym is used to evaluate anchors?

Answer 8

SERENE

Question 9

What does SERENE stand for?

Answer 9

SOLID EFFICIENT REDUNDANT EQUALISING NON-EXTENDING Evaluates every aspect to consider when evaluating an anchor

If any point is not satisfactory, redesign the anchor system.

Question 10

What are the three types of forces that can be placed on an anchor?

Answer 10

• Static force
• Dynamic force
• Shock load force

Question 11

Define static force.

Answer 11

The force applied by a load that is not moving.

Question 12

What is dynamic force?

Answer 12

Applied due to movement of the attached load and can be greater than static force.

Question 13

What is a fall factor?

Answer 13

The distance the load travels divided by the length of rope.

Question 14

What is the range of fall factors?

Answer 14

Theoretically from 0 to 2.

Question 15

What is shock loading?

Answer 15

The sudden increase in force applied to a system due to the arrest of uncontrolled movement of a load.

Question 16

What are the three ways to apply force onto an anchor?

Answer 16

• Shear force
• Tension force
• Compression force

Question 17

Define shear force.

Answer 17

Applied on an object when loaded at 90 degrees to its major axis.

Question 18

What is tension force?

Answer 18

Applied to an object when it is loaded along its major axis, attempting to stretch it.

Question 19

What is compression force?

Answer 19

Applied to an object when loaded along its major axis in the opposite direction to tension force.

Question 20

What are the two modes of anchor failure?

Answer 20

• Partial failure
• Complete failure

Question 21

What is partial failure?

Answer 21

When the component does not break completely but bends, tears, or moves.

Question 22

What is complete failure?

Answer 22

A complete and instantaneous failure of the anchor or other system component.

Question 23

What is a single anchor?

Answer 23

An anchor object considered bomber used to attach a rescue system directly without redundancy.

Question 24

What is the purpose of a tensionless hitch?

Answer 24

To maintain full strength of the line, as the knot will never be under load.

Question 25

What is a Figure 8 Follow Through knot?

Answer 25

A simple, quick, and easy to tie knot.

Question 26

What are the two main reasons a single anchor is often not suitable?

Answer 26

* Not strong enough to take the rescue load * Location is not ideal for the rescue system

Question 27

What is a bomber anchor?

Answer 27

A strong anchor suitable for taking a rescue load ## Footnote A single bomber anchor is ideal but not always available.

Question 28

What are the two main reasons a single anchor is often unsuitable?

Answer 28

* The anchor is not considered strong enough to take the rescue load * The location of the anchor is not ideal for the rescue system

Question 29

What is a pre-tensioned back-tie?

Answer 29

A method of backing up an anchor deemed not strong enough to carry the proposed load

Question 30

How does pre-tensioning affect the primary anchor?

Answer 30

It reduces and sometimes eliminates movement of the primary anchor

Question 31

What must be crossed over at the primary anchor when creating a pre-tension back-tie?

Answer 31

A Wrap 3 Pull 2 or Basket Hitched Sling

Question 32

What type of line should be used for the rescue system?

Answer 32

Life rescue line

Question 33

What is a slack backup?

Answer 33

A backup used when there's an obstruction between the anchor and the backup anchor, providing redundancy, not support

Question 34

What is the purpose of a load-sharing system?

Answer 34

To use multiple anchors connected to a focal point to share the rescue load

Question 35

What happens to load distribution when the leg lengths in a load-sharing anchor are unequal?

Answer 35

The forces and loads will be shared unequally due to rope stretch

Question 36

What is the effect of lateral movement in a load-sharing anchor system?

Answer 36

It can unload one anchor and potentially overload the other anchors

Question 37

What is a key consideration when constructing load-sharing anchors?

Answer 37

Maintain suitable sling leg angles

Question 38

What is the difference between load sharing and load equalising systems?

Answer 38

Load equalising systems allow for lateral movement while maintaining equal load sharing

Question 39

What can happen if one of the anchors in a load equalising system fails?

Answer 39

Extension of the system away from the anchors occurs, potentially causing shock loading

Question 40

What should be included when using slings or closed loops of rope in load sharing?

Answer 40

Always include a twist on one strand to trap the carabiner in the system

Question 41

What happens at 0-30° angle in load distribution?

Answer 41

Each anchor supports 50% of the total weight theoretically, but lateral movement can increase load on one anchor

Question 42

What is the load supported on each anchor at 90°?

Answer 42

70% of the weight of the load

Question 43

What is the critical angle beyond which anchors can become overloaded?

Answer 43

120°

Question 44

How do you estimate sling load angles in the field?

Answer 44

By using fingers to approximate angles

Question 45

What is the purpose of redirects in rescue systems?

Answer 45

* Clear an obstruction * Make an edge transition safer * Ease operation of the system

Question 46

Why are the angles and loads for redirects the inverse of the sling load angles?

Answer 46

To hold a load in position, you must apply the same amount of force on the opposite side of the system