Friday, 25 February 2011 16:57

Avalanches: Hazards and Protective Measures

Rate this item
(3 votes)

Ever since people began to settle in mountainous regions, they have been exposed to the specific hazards associated with mountain living. Among the most treacherous hazards are avalanches and landslides, which have taken their toll of victims even up to the present day.

When the mountains are covered with several feet of snow in winter, under certain conditions, a mass of snow lying like a thick blanket on the steep slopes or mountain tops can become detached from the ground underneath and slide downhill under its own weight. This can result in huge quantities of snow hurtling down the most direct route and settling into the valleys below. The kinetic energy thus released produces dangerous avalanches, which sweep away, crush or bury everything in their path.

Avalanches can be divided into two categories according to the type and condition of the snow involved: dry snow or “dust” avalanches, and wet snow or “ground” avalanches. The former are dangerous because of the shock waves they set off, and the latter because of their sheer volume, due to the added moisture in the wet snow, flattening everything as the avalanche rolls downhill, often at high speeds, and sometimes carrying away sections of the subsoil.

Particularly dangerous situations can arise when the snow on large, exposed slopes on the windward side of the mountain is compacted by the wind. Then it often forms a cover, held together only on the surface, like a curtain suspended from above, and resting on a base that can produce the effect of ball-bearings. If a “cut” is made in such a cover (e.g., if a skier leaves a track across the slope), or if for any reason, this very thin cover is torn apart (e.g., by its own weight), then the whole expanse of snow can slide downhill like a board, usually developing into an avalanche as it progresses.

In the interior of the avalanche, enormous pressure can build up, which can carry off, smash or crush locomotives or entire buildings as though they were toys. That human beings have very little chance of surviving in such an inferno is obvious, bearing in mind that anyone who is not crushed to death is likely to die from suffocation or exposure. It is not surprising, therefore, in cases where people have been buried in avalanches, that, even if they are found immediately, about 20% of them are already dead.

The topography and vegetation of the area will cause the masses of snow to follow set routes as they come down to the valley. People living in the region know this from observation and tradition, and therefore keep away from these danger zones in the winter.

In earlier times, the only way to escape such dangers was to avoid exposing oneself to them. Farmhouses and settlements were built in places where topographical conditions were such that avalanches could not occur, or which years of experience had shown to be far removed from any known avalanche paths. People even avoided the mountain areas altogether during the danger period.

Forests on the upper slopes also afford considerable protection against such natural disasters, as they support the masses of snow in the threatened areas and can curb, halt or divert avalanches that have already started, provided they have not built up too much momentum.

Nevertheless, the history of mountainous countries is punctuated by repeated disasters caused by avalanches, which have taken, and still take, a heavy toll of life and property. On the one hand, the speed and momentum of the avalanche is often underestimated. On the other hand, avalanches will sometimes follow paths which, on the basis of centuries of experience, have not previously been considered to be avalanche paths. Certain unfavourable weather conditions, in conjunction with a particular quality of snow and the state of the ground underneath (e.g., damaged vegetation or erosion or loosening of the soil as a result of heavy rains) produce circumstances that can lead to one of those “disasters of the century”.

Whether an area is particularly exposed to the threat of an avalanche depends not only on prevailing weather conditions, but to an even greater extent on the stability of the snow cover, and on whether the area in question is situated in one of the usual avalanche paths or outlets. There are special maps showing areas where avalanches are known to have occurred or are likely to occur as a result of topographical features, especially the paths and outlets of frequently occurring avalanches. Building is prohibited in high-risk areas.

However, these precautionary measures are no longer sufficient today, as, despite the prohibition of building in particular areas, and all the information available on the dangers, increasing numbers of people are still attracted to picturesque mountain regions, causing more and more building even in areas known to be dangerous. In addition to this disregard or circumvention of building bans, one of the manifestations of the modern leisure society is that thousands of tourists go to the mountains for sport and recreation in winter, and to the very areas where avalanches are virtually pre-programmed. The ideal ski slope is steep, free of obstacles and should have a sufficiently thick carpet of snow—ideal conditions for the skier, but also for the snow to sweep down into the valley.

If, however, risks cannot be avoided or are to a certain extent consciously accepted as an unwelcome “side-effect” of the enjoyment gained from the sport, then it becomes necessary to develop ways and means of coping with these dangers in another manner.

To improve the chances of survival for people buried in avalanches, it is essential to provide well-organized rescue services, emergency telephones near the localities at risk and up-to-date information for the authorities and for tourists on the prevailing situation in dangerous areas. Early warning systems and excellent organization of rescue services with the best possible equipment can considerably increase chances of survival for people buried in avalanches, as well as reducing the extent of the damage.

Protective Measures

Various methods of protection against avalanches have been developed and tested all over the world, such as cross-frontier warning services, barriers and even the artificial triggering-off of avalanches by blasting or firing guns over the snow fields.

The stability of the snow cover is basically determined by the ratio of mechanical stress to density. This stability can vary considerably according to the type of stress (e.g., pressure, tension, shearing strain) within a geographical region (e.g., that part of the snow field where an avalanche might start). Contours, sunshine, winds, temperature and local disturbances in the structure of the snow cover—resulting from rocks, skiers, snowploughs or other vehicles—can also affect stability. Stability can therefore be reduced by deliberate local intervention such as blasting, or increased by the installation of additional supports or barriers. These measures, which can be of a permanent or temporary nature, are the two main methods used for protection against avalanches.

Permanent measures include effective and durable structures, support barriers in the areas where the avalanche might start, diversionary or braking barriers on the avalanche path, and blocking barriers in the avalanche outlet area. The object of temporary protective measures is to secure and stabilize the areas where an avalanche might start by deliberately triggering off smaller, limited avalanches to remove the dangerous quantities of snow in sections.

Support barriers artificially increase the stability of the snow cover in potential avalanche areas. Drift barriers, which prevent additional snow from being carried by the wind to the avalanche area, can reinforce the effect of support barriers. Diversionary and braking barriers on the avalanche path and blocking barriers in the avalanche outlet area can divert or slow down the descending mass of snow and shorten the outflow distance in front of the area to be protected. Support barriers are structures fixed in the ground, more or less perpendicular to the slope, which put up sufficient resistance to the descending mass of snow. They must form supports reaching up to the surface of the snow. Support barriers are usually arranged in several rows and must cover all parts of the terrain from which avalanches could, under various possible weather conditions, threaten the locality to be protected. Years of observation and snow measurement in the area are required in order to establish correct positioning, structure and dimensions.

The barriers must have a certain permeability to let minor avalanches and surface landslides flow through a number of barrier rows without getting larger or causing damage. If permeability is not sufficient, there is the danger that the snow will pile up behind the barriers, and subsequent avalanches will slide over them unimpeded, carrying further masses of snow with them.

Temporary measures, unlike the barriers, can also make it possible to reduce the danger for a certain length of time. These measures are based on the idea of setting off avalanches by artificial means. The threatening masses of snow are removed from the potential avalanche area by a number of small avalanches deliberately triggered off under supervision at selected, predetermined times. This considerably increases the stability of the snow cover remaining on the avalanche site, by at least reducing the risk of further and more dangerous avalanches for a limited period of time when the threat of avalanches is acute.

However, the size of these artificially produced avalanches cannot be determined in advance with any great degree of accuracy. Therefore, in order to keep the risk of accidents as low as possible, while these temporary measures are being carried out, the entire area to be affected by the artificial avalanche, from its starting point to where it finally comes to a halt, must be evacuated, closed off and checked beforehand.

The possible applications of the two methods of reducing hazards are fundamentally different. In general, it is better to use permanent methods to protect areas that are impossible or difficult to evacuate or close off, or where settlements or forests could be endangered even by controlled avalanches. On the other hand, roads, ski runs and ski slopes, which are easy to close off for short periods, are typical examples of areas in which temporary protective measures can be applied.

The various methods of artificially setting off avalanches involve a number of operations which also entail certain risks and, above all, require additional protective measures for persons assigned to carry out this work. The essential thing is to cause initial breaks by setting off artificial tremors (blasts). These will sufficiently reduce the stability of the snow cover to produce a snow-slip.

Blasting is especially suitable for releasing avalanches on steep slopes. It is usually possible to detach small sections of snow at intervals and thus avoid major avalanches, which take a long distance to run their course and can be extremely destructive. However, it is essential that the blasting operations be carried out at any time of day and in all types of weather, and this is not always possible. Methods of artificially producing avalanches by blasting differ considerably according to the means used to reach the area where the blasting is to take place.

Areas where avalanches are likely to start can be bombarded with grenades or rockets from safe positions, but this is successful (i.e., produces the avalanche) in only 20 to 30% of cases, as it is virtually impossible to determine and to hit the most effective target point with any accuracy from a distance, and also because the snow cover absorbs the shock of the explosion. Besides, shells may fail to go off.

Blasting with commercial explosives directly into the area where avalanches are likely to start is generally more successful. The most successful methods are those whereby the explosive is carried on stakes or cables over the part of the snow field where the avalanche is to start, and detonated at a height of 1.5 to 3 m above the snow cover.

Apart from the shelling of the slopes, three different methods have been developed for getting the explosive for the artificial production of avalanches to the actual location where the avalanche is to start:

  • dynamite cableways
  • blasting by hand
  • throwing or lowering the explosive charge from helicopters.


The cableway is the surest and at the same time the safest method. With the help of a special small cableway, the dynamite cableway, the explosive charge is carried on a winding rope over the blasting location in the area of snow cover in which the avalanche is to start. With proper rope control and with the help of signals and markings, it is possible to steer accurately towards what are known from experience to be the most effective locations, and to get the charge to explode directly above them. The best results with respect to triggering off avalanches are achieved when the charge is detonated at the correct height above the snow cover. Since the cableway runs at a greater height above the ground, this requires the use of lowering devices. The explosive charge hangs from a string wound around the lowering device. The charge is lowered to the correct height above the site selected for the explosion with the help of a motor which unwinds the string. The use of dynamite cableways makes it possible to carry out the blasting from a safe position, even with poor visibility, by day or night.

Because of the good results obtained and the relatively low production costs, this method of setting off avalanches is used extensively in the entire Alpine region, a licence being required to operate dynamite cableways in most Alpine countries. In 1988, an intensive exchange of experience in this field took place between manufacturers, users and government representatives from the Austrian, Bavarian and Swiss Alpine areas. The information gained from this exchange of experience has been summarized in leaflets and legally binding regulations. These documents basically contain the technical safety standards for equipment and installations, and instructions on carrying out these operations safely. When preparing the explosive charge and operating the equipment, the blasting crew must be able to move as freely as possible around the various cableway controls and appliances. There must be safe and easily accessible footpaths to enable the crew to leave the site quickly in case of emergency. There must be safe access routes up to cableway supports and stations. In order to avoid failure to explode, two fuses and two detonators must be used for every charge.

In the case of blasting by hand, a second method for artificially producing avalanches, which was frequently done in earlier times, the dynamiter has to climb to the part of the snow cover where the avalanche is to be set off. The explosive charge can be placed on stakes planted in the snow, but more generally thrown down the slope towards a target point known from experience to be particularly effective. It is usually imperative for helpers to secure the dynamiter with a rope throughout the entire operation. Nonetheless, however carefully the blasting team proceeds, the danger of falling or of encountering avalanches on the way to the blasting site cannot be eliminated, as these activities often involve long ascents, sometimes under unfavourable weather conditions. Because of these hazards, this method, which is also subject to safety regulations, is rarely used today.

Using helicopters, a third method, has been practised for many years in the Alpine and other regions for operations to set off avalanches. In view of the dangerous risks for persons on board, this procedure is used in most Alpine and other mountainous countries only when it is urgently needed to avert an acute danger, when other procedures cannot be used or would involve even greater risk. In view of the special legal situation arising from the use of aircraft for such purposes and the risks involved, specific guidelines on setting off avalanches from helicopters have been drawn up in the Alpine countries, with the collaboration of the aviation authorities, the institutions and authorities responsible for occupational health and safety, and experts in the field. These guidelines deal not only with matters concerning the laws and regulations on explosives and safety provisions, but also are concerned with the physical and technical qualifications required of persons entrusted with such operations.

Avalanches are set off from helicopters either by lowering the charge on a rope and detonating it above the snow cover or by dropping a charge with its fuse already lit. The helicopters used must be specially adapted and licensed for such operations. With regard to safely carrying out the operations on board, there must be a strict division of responsibilities between the pilot and the blasting technician. The charge must be correctly prepared and the length of fuse selected according to whether it is to be lowered or dropped. In the interests of safety, two detonators and two fuses must be used, as in the case of the other methods. As a rule, the individual charges contain between 5 and 10 kg of explosive. Several charges can be lowered or dropped one after the other during one operational flight. The detonations must be visually observed in order to check that none has failed to go off.

All these blasting processes require the use of special explosives, effective in cold conditions and not sensitive to mechanical influences. Persons assigned to carry out these operations must be specially qualified and have the relevant experience.

Temporary and permanent protective measures against avalanches were originally designed for distinctly different areas of application. The costly permanent barriers were mainly constructed to protect villages and buildings especially against major avalanches. The temporary protective measures were originally limited almost exclusively to protecting roads, ski resorts and amenities which could be easily closed off. Nowadays, the tendency is to apply a combination of the two methods. To work out the most effective safety programme for a given area, it is necessary to analyse the prevailing situation in detail in order to determine the method that will provide the best possible protection.



Read 8074 times Last modified on Tuesday, 26 July 2022 21:08

" DISCLAIMER: The ILO does not take responsibility for content presented on this web portal that is presented in any language other than English, which is the language used for the initial production and peer-review of original content. Certain statistics have not been updated since the production of the 4th edition of the Encyclopaedia (1998)."


Disasters, Natural and Technological References

American Psychiatric Association (APA). 1994. DSM-IV Diagnostic and Statistical Manual of Mental Disorders. Washington, DC: APA.


Andersson, N, M Kerr Muir, MK Ajwani, S Mahashabde, A Salmon, and K Vaidyanathan. 1986. Persistent eye watering among Bhopal survivors. Lancet 2:1152.


Baker, EL, M Zack, JW Miles, L Alderman, M Warren, RD Dobbin, S Miller, and WR Teeters. 1978. Epidemic malathion poisoning in Pakistan malaria working. Lancet 1:31-34.


Baum, A, L Cohen, and M Hall. 1993. Control and intrusive memories as possible determinants of chronic stress. Psychosom Med 55:274-286.


Bertazzi, PA. 1989. Industrial disasters and epidemiology. A review of recent experiences. Scand J Work Environ Health 15:85-100.


—. 1991. Long-term effects of chemical disasters. Lessons and result from Seveso. Sci Total Environ 106:5-20.


Bromet, EJ, DK Parkinson, HC Schulberg, LO Dunn, and PC Condek. 1982. Mental health of residents near the Three Mile Island reactor: A comparative study of selected groups. J Prev Psychiat 1(3):225-276.


Bruk, GY, NG Kaduka, and VI Parkhomenko. 1989. Air contamination by radionuclides as a result of the accident at the Chernobyl power station and its contribution to inner irradiation of the population (in Russian). Materials of the First All-Union Radiological Congress, 21-27 August, Moscow. Abstracts (in Russian). Puschkino, 1989, vol. II:414-416.


Bruzzi, P. 1983. Health impact of the accidental release of TCDD at Seveso. In Accidental Exposure to Dioxins. Human Health Aspects, edited by F Coulston and F Pocchiari. New York: Academic Press.


Cardis, E, ES Gilbert, and L Carpenter. 1995. Effects of low doses and low dose rates of external ionizing radiation: Cancer mortality among nuclear industry workers in three countries. Rad Res 142:117-132.


Centers for Disease Control (CDC). 1989. The Public Health Consequences of Disasters. Atlanta: CDC.


Centro Peruano-Japones de Investigaciones Sismicas y Mitigacióm de Desastres. Universidad Nacional de Ingeniería (CISMID). 1989. Seminario Internacional De Planeamiento Diseño,


Reparación Y Adminstración De Hospitales En Zonas Sísmicas: Conclusiones Y Recommendaciones. Lima: CISMID/Univ Nacional de Ingeniería.


Chagnon, SAJR, RJ Schicht, and RJ Semorin. 1983. A Plan for Research on Floods and their Mitigation in the United States. Champaign, Ill: Illinois State Water Survey.


Chen, PS, ML Luo, CK Wong, and CJ Chen. 1984. Polychlorinated biphenyls, dibenzofurans, and quaterphenyls in toxic rice-bran oil and PCBs in the blood of patients with PCB poisoning in Taiwan. Am J Ind Med 5:133-145.


Coburn, A and R Spence. 1992. Earthquake Protection. Chichester: Wiley.


Council of the European Communities (CEC). 1982. Council Directive of 24 June on the major accident hazards of certain industrial activities (82/501/EEC). Off J Eur Communities L230:1-17.


—. 1987. Council Directive of 19 March amending Directive 82/501/EEC on the major accident hazards of certain industrial activities (87/216/EEC). Off J Eur Communities L85:36-39.


Das, JJ. 1985a. Aftermath of Bhopal tragedy. J Indian Med Assoc 83:361-362.


—. 1985b. The Bhopal tragedy. J Indian Med Assoc 83:72-75.


Dew, MA and EJ Bromet. 1993. Predictors of temporal patterns of psychiatric distress during ten years following the nuclear accident at Three Mile Island. Social Psych Psychiatric Epidemiol 28:49-55.


Federal Emergency Management Agency (FEMA). 1990. Seismic considerations: Health care facilities. Earthquake Hazard Reduction Series, No. 35. Washington, DC: FEMA.


Frazier, K. 1979. The Violent Face of Nature: Severe Phenomena and Natural Disasters. Floods. New York: William Morrow & Co.


Freidrich Naumann Foundation. 1987. Industrial Hazards in Transnational Work: Risk, Equity and Empowerment. New York: Council on International and Public Affairs.


French, J and K Holt. 1989. Floods: Public Health Consequences of Disasters. Centers for Disease Control Monograph. Atlanta: CDC.


French, J, R Ing, S Von Allman, and R Wood. 1983. Mortality from flash floods: A review of National Weather Service reports, 1969-1981. Publ Health Rep 6(November/December):584-588.


Fuller, M. 1991. Forest Fires. New York: John Wiley.


Gilsanz, V, J Lopez Alverez, S Serrano, and J Simon. 1984. Evolution of the alimentary toxic oil syndrome due to ingestion of denatured rapeseed oil. Arch Int Med 144:254-256.


Glass, RI, RB Craven, and DJ Bregman. 1980. Injuries from the Wichita Falls tornado: Implications for prevention. Science 207:734-738.


Grant, CC. 1993. Triangle fire stirs outrage and reform. NFPA J 87(3):72-82.


Grant, CC and TJ Klem. 1994. Toy factory fire in Thailand kills 188 workers. NFPA J 88(1):42-49.


Greene, WAJ. 1954. Psychological factors and reticuloendothelial disease: Preliminary observations on a group of males with lymphoma and leukemia. Psychosom Med:16-20.


Grisham, JW. 1986. Health Aspects of the Disposal of Waste Chemicals. New York: Pergamon Press.


Herbert, P and G Taylor. 1979. Everything you always wanted to know about hurricanes: Part 1. Weatherwise (April).


High, D, JT Blodgett, EJ Croce, EO Horne, JW McKoan, and CS Whelan. 1956. Medical aspects of the Worcester tornado disaster. New Engl J Med 254:267-271.


Holden, C. 1980. Love Canal residents under stress. Science 208:1242-1244.


Homberger, E, G Reggiani, J Sambeth, and HK Wipf. 1979. The Seveso accident: Its nature, extent and consequences. Ann Occup Hyg 22:327-370.


Hunter, D. 1978. The Diseases of Occupations. London: Hodder & Stoughton.


International Atomic Energy Agency (IAEA). 1988. Basic Safety Principles for Nuclear Power Plants INSAG-3. Safety Series, No. 75. Vienna: IAEA.


—. 1989a. L’accident radiologique de Goiânia. Vienna: IAEA.


—. 1989b. A large-scale Co-60 contamination case: Mexico 1984. In Emergency Planning and Preparedness for Accidents Involving Radioactive Materials Used in Medicine, Industry, Research and Teaching. Vienna: IAEA.


—. 1990. Recommendations for the Safe Use and Regulation of Radiation Sources in Industry, Medicine, Reasearch and Teaching. Safety Series, No. 102. Vienna: IAEA.


—. 1991. The International Chernobyl Project. Technical report, assessment of radiological consequences and evaluation of protective measures, report by an International Advisory Committee. Vienna: IAEA.


—. 1994. Intervention Criteria in a Nuclear or Radiation Emergency. Safety Series, No. 109. Vienna: IAEA.


International Commission on Radiological Protection (ICRP). 1991. Annals of the ICRP. ICRP Publication No. 60. Oxford: Pergamon Press.


International Federation of Red Cross and Red Crescent Societies (IFRCRCS). 1993. The World Disaster Report. Dordrecht: Martinus Nijhoff.


International Labour Organization (ILO). 1988. Major Hazard Control. A Practical Manual. Geneva: ILO.


—. 1991. Prevention of Major Industrial Accidents. Geneva: ILO.


—. 1993. Prevention of Major Industrial Accidents Convention, 1993 (No. 174). Geneva: ILO.


Janerich, DT, AD Stark, P Greenwald, WS Bryant, HI Jacobson, and J McCusker. 1981. Increased leukemia, lymphoma and spontaneous abortion in Western New York following a disaster. Publ Health Rep 96:350-356.


Jeyaratnam, J. 1985. 1984 and occupational health in developing countries. Scand J Work Environ Health 11:229-234.


Jovel, JR. 1991. Los efectos económicos y sociales de los desastres naturales en América Latina y el Caribe. Santiago, Chile: Document presented at the First Regional UNDP/UNDRO Disaster Management Training Program in Bogota, Colombia.


Kilbourne, EM, JG Rigau-Perez, J Heath CW, MM Zack, H Falk, M Martin-Marcos, and A De Carlos. 1983. Clinical epidemiology of toxic-oil syndrome. New Engl J Med 83:1408-1414.


Klem, TJ. 1992. 25 die in food plant fire. NFPA J 86(1):29-35.


Klem, TJ and CC Grant. 1993. Three Workers Die in Electrical Power Plant Fire. NFPA J 87(2):44-47.


Krasnyuk, EP, VI Chernyuk, and VA Stezhka. 1993. Work conditions and health status of operators of agricultural machines in areas being under control due to the Chernobyl accident (in Russian). In abstracts Chernobyl and Human Health Conference, 20-22 April.


Krishna Murti, CR. 1987. Prevention and control of chemical accidents: Problems of developing countries. In Istituto Superiore Sanita’, World Health Organization, International Programme On Chemical Safety. Edinburgh: CEP Consultants.


Lancet. 1983. Toxic oil syndrome. 1:1257-1258.


Lechat, MF. 1990. The epidemiology of health effects of disasters. Epidemiol Rev 12:192.


Logue, JN. 1972. Long term effects of a major natural disaster: The Hurricane Agnes flood in the Wyoming Valley of Pennsylvania, June 1972. Ph.D. Dissertation, Columbia Univ. School of Public Health.


Logue, JN and HA Hansen. 1980. A case control study of hypertensive women in a post-disaster community: Wyoming Valley, Pennsylvania. J Hum Stress 2:28-34.


Logue, JN, ME Melick, and H Hansen. 1981. Research issues and directions in the epidemiology of health effects of disasters. Epidemiol Rev 3:140.


Loshchilov, NA, VA Kashparov, YB Yudin, VP Proshchak, and VI Yushchenko. 1993. Inhalation intake of radionuclides during agricultural works in the areas contaminated by radionuclides due to the Chernobyl accident (in Russian). Gigiena i sanitarija (Moscow) 7:115-117.


Mandlebaum, I, D Nahrwold, and DW Boyer. 1966. Management of tornado casualties. J Trauma 6:353-361.


Marrero, J. 1979. Danger: Flash floods—the number one killer of the 70’s. Weatherwise (February):34-37.


Masuda, Y and H Yoshimura. 1984. Polychlorinated biphenyls and dibenzofurans in patients with Yusho and their toxicological significance: A review. Am J Ind Med 5:31-44.


Melick, MF. 1976. Social, psychological and medical aspects of stress related illness in the recovery period of a natural disaster. Dissertation, Albany, State Univ. of New York.


Mogil, M, J Monro, and H Groper. 1978. NWS’s flash flood warning and disaster preparedness programs. B Am Meteorol Soc :59-66.


Morrison, AS. 1985. Screening in Chronic Disease. Oxford: OUP.


National Fire Protection Association (NFPA). 1993. National Fire Alarm Code. NFPA No. 72. Quincy, Mass: NFPA.


—. 1994. Standard for the Installation of Sprinkler Systems. NFPA No. 13. Quincy, Mass: NFPA.


—. 1994. Life Safety Code. NFPA No. 101. Quincy, Mass: NFPA.


—. 1995. Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems. NFPA No. 25. Quincy, Mass: NFPA.


Nénot, JC. 1993. Les surexpositions accidentelles. CEA, Institut de Protection et de Sûreté Nucléaire. Rapport DPHD/93-04.a, 1993, 3-11.


Nuclear Energy Agency. 1987. The Radiological Impact of the Chernobyl Accident in OECD Countries. Paris: Nuclear Energy Agency.


Otake, M and WJ Schull. 1992. Radiation-related Small Head Sizes among Prenatally Exposed Atomic Bomb Survivors. Technical Report Series, RERF 6-92.


Otake, M, WJ Schull, and H Yoshimura. 1989. A Review of Radiation-related Damage in the Prenatally Exposed Atomic Bomb Survivors. Commentary Review Series, RERF CR 4-89.


Pan American Health Organization (PAHO). 1989. Analysis of PAHO’s Emergency Preparedness and Disaster Relief Program. Executive Committee document SPP12/7. Washington, DC: PAHO.


—. 1987. Crónicas de desastre: terremoto en México. Washington, DC: PAHO.


Parrish, RG, H Falk, and JM Melius. 1987. Industrial disasters: Classification, investigation, and prevention. In Recent Advances in Occupational Health, edited by JM Harrington. Edinburgh: Churchill Livingstone.


Peisert, M comp, RE Cross, and LM Riggs. 1984. The Hospital’s Role in Emergency Medical Services Systems. Chicago: American Hospital Publishing.


Pesatori, AC. 1995. Dioxin contamination in Seveso: The social tragedy and the scientific challenge. Med Lavoro 86:111-124.


Peter, RU, O Braun-Falco, and A Birioukov. 1994. Chronic cutaneous damage after accidental exposure to ionizing radiation: The Chernobyl experience. J Am Acad Dermatol 30:719-723.


Pocchiari, F, A DiDomenico, V Silano, and G Zapponi. 1983. Environmental impact of the accidental release of tetrachlorodibenzo-p-dioxin(TCDD) at Seveso. In Accidental Exposure to Dioxins: Human Health Aspects, edited by F Coulston and F Pocchiari. New York: Academic Press.


—. 1986. The Seveso accident and its aftermath. In Insuring and Managing Hazardous Risks: From Seveso to Bhopal and Beyond, edited by PR Kleindorfer and HC Kunreuther. Berlin: Springer-Verlag.


Rodrigues de Oliveira, A. 1987. Un répertoire des accidents radiologiques 1945-1985. Radioprotection 22(2):89-135.


Sainani, GS, VR Joshi, PJ Mehta, and P Abraham. 1985. Bhopal tragedy -A year later. J Assoc Phys India 33:755-756.


Salzmann, JJ. 1987. ìSchweizerhalleî and Its Consequences. Edinburgh: CEP Consultants.


Shore, RE. 1992. Issues and epidemiological evidences regarding radiation-induced thyroid cancer. Rad Res 131:98-111.


Spurzem, JR and JE Lockey. 1984. Toxic oil syndrome. Arch Int Med 144:249-250.


Stsjazhko, VA, AF Tsyb, ND Tronko, G Souchkevitch, and KF Baverstock. 1995. Childhood thyroid cancer since accidents at Chernobyl. Brit Med J 310:801.


Tachakra, SS. 1987. The Bhopal Disaster. Edinburgh: CEP Consultants.


Thierry, D, P Gourmelon, C Parmentier, and JC Nenot. 1995. Hematopoietic growth factors in the treatment of therapeutic and accidental irradiation-induced aplasia. Int J Rad Biol (in press).


Understanding Science and Nature: Weather and Climate. 1992. Alexandria, Va: Time-Life.


United Nations Disaster Relief Coordinator Office (UNDRO). 1990. Iran earthquake. UNDRO News 4 (September).


United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). 1988. Sources, Effects and Risks of Ionizing Radiation. New York: UNSCEAR.


—. 1993. Sources and Effects of Ionizing Radiation. New York: UNSCEAR.


—. 1994. Sources and Effects of Ionizing Radiation. New York: UNSCEAR.


Ursano, RJ, BG McCaughey, and CS Fullerton. 1994. Individual and Community Responses to Trauma and Disaster: The Structure of Human Chaos. Cambridge: Cambridge Univ. Press.


US Agency for International Development, (USAID). 1989. Soviet Union: Earthquake. OFDA/AID Annual Report, FY1989. Arlington, Va: USAID.


Walker, P. 1995. World Disaster Report. Geneva: International Federation of Red Cross and Red Crescent Societies.


Wall Street J. 1993 Thailand fire shows region cuts corners on safety to boost profits, 13 May.


Weiss, B and TW Clarkson. 1986. Toxic chemical disaster and the implication of Bhopal for technology transfer. Milbank Q 64:216.


Whitlow, J. 1979. Disasters: The Anatomy of Environmental Hazards. Athens, Ga: Univ. of Georgia Press.


Williams, D, A Pinchera, A Karaoglou, and KH Chadwick. 1993. Thyroid Cancer in Children Living Near Chernobyl. Expert panel report on the consequences of the Chernobyl accident, EUR 15248 EN. Brussels: Commission of the European Communities (CEC).


World Health Organization (WHO). 1984. Toxic Oil Syndrome. Mass Food Poisoning in Spain. Copenhagen: WHO Regional office for Europe.


Wyllie, L and M Durkin. 1986. The Chile earthquake of March 3, 1985: Casualties and effects on the health care system. Earthquake Spec 2(2):489-495.


Zeballos, JL. 1993a. Los desastres quimicos, capacidad de respuesta de los paises en vias de desarrollo. Washington, DC: Pan American Health Organization (PAHO).


—. 1993b. Effects of natural disasters on the health infrastructure: Lessons from a medical perspective. Bull Pan Am Health Organ 27: 389-396.


Zerbib, JC. 1993. Les accidents radiologiques survenus lors d’usages industriels de sources radioactives ou de générateurs électirques de rayonnement. In Sécurité des sources radioactives scellées et des générateurs électriques de rayonnement. Paris: Société française de radioprotection.