Risk-Informed Approaches to Safety Regulation - Structural Integrity of Offshore Wind Turbines - page 134

have increased the contribution of risk analysis to the rational development
of design criteria, which, owing to current computational capabilities, can
be far better differentiated and realistic than their 1970s counterparts.
This appendix summarizes basic concepts of modern risk-informed
safety regulation as they are currently utilized in the design of civil infra-
structure and discusses their application to structural design require-
ments for mitigation of risk in the built environment.
FUNDAMENTALS OF RISK ASSESSMENT FOR NATURAL
AND MAN-MADE HAZARDS
Risk analysis and assessment tools are essential in measuring compliance
with performance objectives, in comparing alternatives rationally, and
in highlighting the role of uncertainty in the decision process. This sec-
tion outlines a framework for modern risk-informed decision making,
providing the background for the implementation of structural design
requirements for civil infrastructure facilities in the current construction
and regulatory climate.
Risk and Its Analysis: Hazard, Consequences, Context
Risk involves hazard, consequences, and context (Stewart and Melchers 1997;
Vrijling et al. 1998; Faber and Stewart 2003). The hazard is a potentially
harmful event, action, or state of nature. The potential for the occurrence
of a hurricane or earthquake at the site of a structure is a hazard. The occur-
rence of such a hazardous event has potential consequences—building
damage or collapse, loss of life or personal injury, economic losses, or
damage to the environment—which must be measured in terms of a
value system involving some metric. Finally, there is the context of the risk
assessment, which is related to what is at risk, what individuals or agencies
are measuring and assessing the risk and how risk-averse they might be,
the necessity for or feasibility of risk management, and how additional
investment in risk reduction can be balanced against available resources.
Risk Benchmarks in Current Structural Codes
Structural codes and standards and design practice historically have
striven to deliver structural products and systems with risks that the pub-