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close this bookVulnerability and Risk Assessment - 2nd Edition (Department of Humanitarian Affairs/United Nations Disaster Relief Office - Disaster Management Training Programme - United Nations Development Programme , 1994, 70 p.)
View the document(introduction...)
View the documentUnited Nations reorganization and the Disaster Management Training Programme
View the documentIntroduction
Open this folder and view contentsPart 1 - Understanding risk
Open this folder and view contentsPart 2 - Assessing risk and vulnerability
Open this folder and view contentsPart 3 - Appraising disaster mitigation options
View the documentEnd notes
View the documentAnnex 1: Acronyms
View the documentAnnex 2: Additional reading
View the documentGlossary
View the documentModule evaluation

End notes

1. Life expectancy is one of the indicators of development gathered on individual countries in World Development Report, 1989, published for The World Bank by Oxford University Press.

2. UNDRO, 1979, Natural Disasters and Vulnerability Analysis, Report of Expert Group Meeting 9-12 July 1979, Office of the United Nations Disaster Relief Coordinator, Geneva.

3. The general equation for the calculation of risk is: [Rij] = [Hj ] × [Vij] where, for an Element at Risk, (e.g. an individual building) i, in a given unit of time:

[Rij] is the Specific Risk; the probable loss to element i due to a hazard of severity j.

[Hj] is the Hazard; the probability of experiencing a hazardous event of severity j.

[Vij] is the Vulnerability; the level of loss that would be caused to element i as a result of experiencing a hazard of severity j.

By summing the risk from all levels of hazard, (min £ j £ max), the total specific risk to any individual element can be derived. The Risk is then the product of the Specific Risk and the value of the element at risk.

4. Risk assessment and evaluation is differentiated in Living with Risk, 1987, The British Medical Association Guide, John Wiley & Sons

5. Probability of an individual dying in any year from various causes is published in Living with Risk, 1987, The British Medical Association Guide, John Wiley & Sons and the statistics in bold type for probability of deaths from natural hazards are added from The Cambridge University Human Casualty database and other sources.

6. Making sense of risk levels is difficult and the format of 'one in...' is probably the easiest to comprehend quickly. With small probabilities, the number of noughts may be difficult to deal with and some probabilities are expressed in a logarithmic scale, called Safety Degree Units or SDUs (the Urquhart and Heilmann scale). In this scale the order of magnitude of the risk is defined a risk of one in 100 and is expressed as 2 - the logarithm of 100, and one in 1,000 is expressed as 3 (a simple guide is the number of noughts). Thus the risk of being killed by an earthquake in Iran is around 4 SDUs, but the risk of a Californian being killed by an earthquake is lower; around 6 SDUs - i.e. one hundred times lower or two orders of magnitude less. In comparing low probability events, the SDU scale may sometimes be more useful.

7. Studies of mountain communities, their risks and their development priorities formed part of the work of the International Karakoram Project: Housing and Hazards Group, 1980, reported in the Proceedings of Royal Geographic Society, 1983.

8. S. Lichtenstein et al., 1978, 'Judged Frequency of Lethal Events', Journal of Experimental Psychology: Human Learning and Memory, Vol 4., No. 6.; American Psychological Association.

9. Villagers living in areas of high seismic risk were interviewed by social scientists in Eastern Anatolia, Turkey as part of a study of risk reduction programs, reported in Bingol Province Field Study. 2-24 August 1982, Turkish National Committee for Earthquake Engineering and The Martin Centre for Architectural and Urban Studies, University of Cambridge.

10. C. Starr, 1969, 'Social Benefit versus Technological Risk: What is Our Society Willing to Pay for Safety?', Science, Vol. 165, p. 1232-1236.

11. L.S. Fryer; R.F. Griffiths, 1986, Worldwide Data on the Incidence of Multiple-Fatality Accidents, United Kingdom Atomic Energy Authority.

12. Presentation of Risk Example 1 is taken from Emergency Planning and Earthquake Damage Reduction for Bursa Province, eds A.W. Coburn and U. Kuran, Project on Regional Planning for Disasters, 1985.

13. Earthquake intensity is a measure of the degree of shaking of the ground at a particular point, expressed as a degree in Roman numerals I to XII. Common intensity scales include the Modified Mercalli (MM) and the Medvedev, Sponheuer, Karnik (MSK) scales.

14. Peak ground acceleration is one of the best measures of the potential damage of earthquake ground motion. Its normal units are meters per second per second, but it is often, for ease of interpretation, expressed in a non-unit form as a percentage of the acceleration due to gravity (g) which equals approximately 9.81 m/sec2.

15. Hazard Map Example 1 is taken from UNDRO, (1977) Composite Vulnerability Analysis: A Methodology and Case Study of the Metro Manila Area, Technical Advisory Mission to the Government of the Philippines, Human Settlements Commission (HSC).

16. Hazard Map Example 2 is taken from a study of Gunung Kelat by Volcanology Division, Geological Survey of Indonesia.

17. Damage Probability Matrix for Landslides taken from ATC-13.

18. The case study of Reducing Disaster Risk in Mexico City Vecindades is a summary of some of the work carried out in Project MEX-86-009, Mitigation of Seismic Risk in Urban Areas, United Nations Development Program, United Nations Centre for Human Settlements (Habitat); Secretaria General de Obras, Departamento del Distrito Federal.

19. Reconstruction after the Mexico earthquake in 1985 is documented in DDF-DGRUPE, 'Programa de Revitalizacion del Centro Historico de la Ciuadad de Mexico'. Direccion General de Reordenacion Urbana y Proteccion Ecologica, September 1986.

20. Y. Aysan, A.W. Coburn, I. Davis, R.J.S. Spence, Mitigation of Urban Seismic Risk: Actions to Reduce the Impact of Earthquakes on Highly Vulnerable Areas of Mexico City, First Year Report of Bilateral Technical Cooperation Agreement between the Governments of Mexico and United Kingdom, April 1989.

21. Human Vulnerability Survey in Mexico City was directed by Oxford Polytechnic Disaster Management Centre, reported in Aysan et al., ibid.

22. Flood vulnerability functions taken from ATC-13, p. 251.

23. Human Vulnerability Survey in Mexico City was directed by Oxford Polytechnic Disaster Management Centre reported in Aysan et al., ibid.

24. M.B. Anderson, 1990, Analyzing the Costs and Benefits of Natural Disaster Responses in the Context of Development, Environment Working Paper No. 29, Policy Planning and Research Staff, The World Bank.

25. M.B. Anderson, ibid.

26. E.C. Penning-Rowsell, J.B. Chatterton, 1980, 'Assessing the Benefits of Flood Alleviation and Land Drainage Schemes', Proc. Instn Civ. Engnrs, Part 2, 69, June, 295-315.

27. The expected losses from a range of geological hazards in the state of California is taken from California Division of Mines and Geology, 1975.

28. Grandori (1982).

29. ATC3-06 Tentative Provisions for Seismic Regulations in California

30. For further discussion of acceptable risk see H.D. Foster, Disaster Planning: The Preservation of Life and Property, Springer-Verlag, 1980.

31. Grandori and Benedetti (1973).

32. Example of costs and benefits of rural upgrading programs for earthquake protection is taken from R.J.S. Spence and A.W. Coburn, Reducing Earthquake Losses in Rural Areas, Overseas Development Administration, United Kingdom, 1987.