BMP - Tree Risk Assessment - 36
Matrix 1. The likelihood matrix used to estimate the likelihood of a tree failure
impacting a specified target.
Likelihood of
Failure
Likelihood of Impact
Imminent
Very Low
Unlikely
Low
Somewhat
likely
Medium
Likely
High
Very likely
Probable
Unlikely
Unlikely
Somewhat
likely
Likely
Possible
Unlikely
Unlikely
Unlikely
Somewhat
likely
Improbable
Unlikely
Unlikely
Unlikely
Unlikely
sor as probable. The house is a static target with a constant occupancy rate. However, the likelihood of the branch falling from the
opposite side of the tree through the rest of the tree to the house is
very low. This results in a likelihood of impacting the house rating of
unlikely.
On the other hand, there is a car parking area located directly under
the branch and there are no lower branches that would mitigate the fall of
the branch. A car is parked under the tree for 14 to 16 hours per day, and
the driver is present for a few minutes each day as she walks between the
house and the car. Thus, the human occupancy rate in the target zone is
rare and the occupancy rate for a car in the parking area is frequent. There
are no factors that would affect the fall of the branch on this side of the
tree, so the rare human occupancy rate translates to a very low likelihood
of impacting the driver. When that is combined with a probable failure
likelihood, the combination results in the likelihood of a failure impacting
the driver as unlikely.
The occupancy rate for a car in the parking area is frequent, making the
likelihood of striking it high. Combining the high likelihood of impact with
the probable likelihood failure of the branch, the likelihood of failure and
impact for the car becomes likely. As illustrated in this example, it is not
unusual to have multiple targets with different values and occupancy rates.
The most important risk targets should be considered when conducting a
risk assessment, and the risk(s) being rated should be defined.
Categorizing Consequences of Failure
The consequences of a tree failing and impacting a target are a function of
the value of the target and the amount of injury, damage, or disruption (harm)
36
BMP - Tree Risk Assessment
Table of Contents for the Digital Edition of BMP - Tree Risk Assessment
Table of Contents
BMP - Tree Risk Assessment - Cover1
BMP - Tree Risk Assessment - Cover2
BMP - Tree Risk Assessment - i
BMP - Tree Risk Assessment - ii
BMP - Tree Risk Assessment - Table of Contents
BMP - Tree Risk Assessment - iv
BMP - Tree Risk Assessment - 1
BMP - Tree Risk Assessment - 2
BMP - Tree Risk Assessment - 3
BMP - Tree Risk Assessment - 4
BMP - Tree Risk Assessment - 5
BMP - Tree Risk Assessment - 6
BMP - Tree Risk Assessment - 7
BMP - Tree Risk Assessment - 8
BMP - Tree Risk Assessment - 9
BMP - Tree Risk Assessment - 10
BMP - Tree Risk Assessment - 11
BMP - Tree Risk Assessment - 12
BMP - Tree Risk Assessment - 13
BMP - Tree Risk Assessment - 14
BMP - Tree Risk Assessment - 15
BMP - Tree Risk Assessment - 16
BMP - Tree Risk Assessment - 17
BMP - Tree Risk Assessment - 18
BMP - Tree Risk Assessment - 19
BMP - Tree Risk Assessment - 20
BMP - Tree Risk Assessment - 21
BMP - Tree Risk Assessment - 22
BMP - Tree Risk Assessment - 23
BMP - Tree Risk Assessment - 24
BMP - Tree Risk Assessment - 25
BMP - Tree Risk Assessment - 26
BMP - Tree Risk Assessment - 27
BMP - Tree Risk Assessment - 28
BMP - Tree Risk Assessment - 29
BMP - Tree Risk Assessment - 30
BMP - Tree Risk Assessment - 31
BMP - Tree Risk Assessment - 32
BMP - Tree Risk Assessment - 33
BMP - Tree Risk Assessment - 34
BMP - Tree Risk Assessment - 35
BMP - Tree Risk Assessment - 36
BMP - Tree Risk Assessment - 37
BMP - Tree Risk Assessment - 38
BMP - Tree Risk Assessment - 39
BMP - Tree Risk Assessment - 40
BMP - Tree Risk Assessment - 41
BMP - Tree Risk Assessment - 42
BMP - Tree Risk Assessment - 43
BMP - Tree Risk Assessment - 44
BMP - Tree Risk Assessment - 45
BMP - Tree Risk Assessment - 46
BMP - Tree Risk Assessment - 47
BMP - Tree Risk Assessment - 48
BMP - Tree Risk Assessment - 49
BMP - Tree Risk Assessment - 50
BMP - Tree Risk Assessment - 51
BMP - Tree Risk Assessment - 52
BMP - Tree Risk Assessment - 53
BMP - Tree Risk Assessment - 54
BMP - Tree Risk Assessment - 55
BMP - Tree Risk Assessment - 56
BMP - Tree Risk Assessment - 57
BMP - Tree Risk Assessment - 58
BMP - Tree Risk Assessment - 59
BMP - Tree Risk Assessment - 60
BMP - Tree Risk Assessment - 61
BMP - Tree Risk Assessment - 62
BMP - Tree Risk Assessment - 63
BMP - Tree Risk Assessment - 64
BMP - Tree Risk Assessment - 65
BMP - Tree Risk Assessment - 66
BMP - Tree Risk Assessment - 67
BMP - Tree Risk Assessment - 68
BMP - Tree Risk Assessment - 69
BMP - Tree Risk Assessment - 70
BMP - Tree Risk Assessment - 71
BMP - Tree Risk Assessment - 72
BMP - Tree Risk Assessment - 73
BMP - Tree Risk Assessment - 74
BMP - Tree Risk Assessment - 75
BMP - Tree Risk Assessment - 76
BMP - Tree Risk Assessment - 77
BMP - Tree Risk Assessment - 78
BMP - Tree Risk Assessment - 79
BMP - Tree Risk Assessment - 80
BMP - Tree Risk Assessment - 81
BMP - Tree Risk Assessment - 82
BMP - Tree Risk Assessment - 83
BMP - Tree Risk Assessment - 84
BMP - Tree Risk Assessment - 85
BMP - Tree Risk Assessment - 86
BMP - Tree Risk Assessment - Cover3
BMP - Tree Risk Assessment - 88
https://www.nxtbookmedia.com