1. HAZARD ANALYSIS The process of defining a hazard … Walter G. Green III, Ph.D., CEM Emergency Management Process Series No. 1 Copyright 2008 by Walter G. Green III

2. HAZARDS  Existing condition or possible (under current conditions) situation that has the potential to generate a disaster  Natural hazards – naturally occurring phenomena – weather, topographic, geological, hydrological, etc.  Human systems developed – caused by human activity, infrastructure, transportation, etc.  Conflict based – civil war, terrorism, nuclear war, etc.

3. THE ANALYSIS PROCESS  (1) identify possible hazards  (2) characterize each hazard  (3) apply a rating or assessment metric  (4) communicate the results

4. IDENTIFYING HAZARDS  Consider two basic realities There is no place on the earth’s surface that is without hazard Almost any hazard can impact almost any place – fewer directly, more indirectly  The result is a list of hazards that is nearly endless for any specific location  How then do we narrow the field?

5. FINDING HAZARDS  (1) Response history  (2) What has happened elsewhere  (3) Hazard survey  (4) Local disaster history  (5) Current scientific knowledge  (6) Environmental sensing  Then do it all again on a regular schedule

6. CHARACTERIZING HAZARDS  It should be obvious that hazards are not identical, not uniform, not exclusive, and not transposable  This means that we have to understand each hazard in the context of its time and place

7. CHARACTERIZING HAZARDS  You must answer all of the following in terms of your situation: Magnitude and intensity ranges? Time, and season? Duration? Timeline of development? Place and extent of impact area? Frequency? Can it be predicted? Related hazards? Cascading effects?

8. OUTCOMES  Higher magnitude and/or intensity = increased hazard  Time and season – a longer period during which these events typically occur = increased hazard  Duration - generally longer duration events = increased hazard  Timeline of development – generally shorter development = increased hazard

9. OUTCOMES  A critical location at risk or a wide- area impact = increased hazard  Higher frequency = increased hazard  Events that can be predicted only with difficulty = higher hazard  Events that are related to and can be triggered by or trigger other events = higher hazard

10. THE TIME HORIZON  Very important to determine what the time horizon of your assessment is  A short time period (“in the next 2 years”) Infrequent events become low hazard Frequent events become high hazard  A longer time period (“in the next 100 years”) Infrequent events increase in hazard  A very long time period (“the next 500 years”) Infrequent catastrophic events become higher hazard

11. ASSESSMENT  Assessing hazards is a very difficult process Wide range of variability in the where, when, what, and how bad of events  In many cases we have insufficient data or understanding to make highly accurate assessments  In other cases time precludes in depth analysis

12. TWO APPROACHES  Qualitative Assesses using fuzzy judgment Communicates in broad categories  Quantitative Assesses using defined criteria Communicates using numbers

13. QUALITATIVE ANALYSIS  [1] Define the levels  [2] Accumulate information  [3] Invite participation by experts  [4] Describe the process and provide an overview  [5] Develop consensus

14. QUALITATIVE TERMS  A possible standard: Extreme - community can no longer function High – large number of deaths, similar number of injuries, wide property damage, function difficult Moderate – small number of deaths, larger number of injuries, wide property damage, function under strain Low – no deaths, few injuries, little property damage, community services function close to normal

15. QUANTITATIVE ANALYSIS  There are a wide variety of approaches: Rating hazards by total number of key factors Rating hazards by points for each key factor Rating hazards by formulas that reflect interactions between components of the hazard

16. TOTAL NUMBER  High magnitude – X  All year hazard – 0  Duration – X  Timeline short – X  Location wide area – X  Frequency annual – 0  Not predicted – X  Related hazards – 0  Cascading effects - 0

17. POINTS  High magnitude – 6  All year hazard – 3  Duration – 8  Timeline short – 10  Location wide area – 10  Frequency annual – 1  Not predicted – 10  Related hazards – 0  Cascading effects - 0

18. THE FORMULA  Magnitude x 2 x number of months of duration  Plus area of potential impact divided by area of community x 10  All x 24 divided by warning time in hours plus a prediction constant  All x frequency of events in a 100 year period divided by100

19. THE FORMULA PROBLEM  Some quantitative analyses use formulas to arrive at numerical values for the hazard level  Check to make sure the mathematics really measure what they say they measure  Common errors are to: add factors that should be multiplied, or vice versa, apply constants that are not constant, and mix values that are unrelated

20. FORMULA EXAMPLE  Your locality has hurricanes and tornadoes as its two primary natural disaster hazards  Which of the following is the best formula to express that relationship? Hurricanes + tornadoes = hazard Hurricanes x tornadoes = hazard Hurricanes or tornadoes = hazard Hurricanes and tornadoes = hazard

21. MIX TYPES?  Do we create one single list of all hazards, or  Separate lists of natural, human systems, or conflict based hazards?  And which goes first?  The answer depends on: The function the analysis performs, The programmatic structure of the organization, and/or Current doctrine

22. PRIORITIZING  Ratings suggest we will rank order the outcomes  Highest to lowest, either overall or by class  Understand that the list is only a guide  But that decision makers will believe it is an absolute reflection of reality

23. THE FUTURE  Hazard analysis for today The typical hazard analysis  Or hazard analysis for tomorrow Project forward to the planning horizon Identify trends Identifying emerging hazards Allows proactive rather than reactive planning for mitigation and preparedness

24. COMMUNICATION  Typically a written report that describes the method used, identifies the hazards, and ranks them  Report should clearly identify the time period for which it is valid, other restrictions to the scope, and underlying assumptions  Distributed as needed  Used as the basis for vulnerability assessment