Titel_SS06

0

20

40

60

80

100

All observed

cases

723

Cost of

damages

Cases with

injuries

60

Combinations

Work preparation

Drawings, etc.

Structural analysis

Concept

(^419)
20
8
40
15
17
95
49
18
34
19
9
34
Figure 1.15: Illustration of the distribution of the phases during planning where risks were
inadequately treated (Matousek and Schneider (1976)).
It is interesting to investigate how the failures and errors, which may be attributed to accepted
risks and human errors, contribute to the total sum of damages, the total number of injuries
and loss of lives and the total number of failures and errors, respectively. This is illustrated in
Figure 1.16.
0
20
40
60
80
100
Number of
damage
cases
Cost of Injuries
damages
Accepted Risk
Human errors
25
85
15
90
75
10
Figure 1.16: Illustration of the total number of injuries and loss of lives, economic consequences and
total number of failures and errors attributed to accepted risks and human errors,
respectively (Matousek and Schneider (1976)).
In Figure 1.17 the distribution of causes of the failures and errors is illustrated. It is seen that
ignorance and insufficient knowledge are the most important contributions to failures and
errors. Followed by causes as underestimation of effects, failing to remember, incorrect
transfer of responsibility and simply not knowing.
Ignorance
37%
Insufficient
knowledge
27%
Underestimation
of effects
14%
Errors,
forgotten
10%
Incorrect transfer of
responsibility
6%
Did not know
5%
Figure 1.17: Distribution of reasons why failures and errors occur (Matousek and Schneider (1976)).