Disasters, Hazards : Definition, Causes, Classification, Types, Management Cycle, Mitigation, Preparedness, & Recovery
- According to WHO, Disaster is any occurrence (such as hurricane, tornado, storm, flood, high water, wind-driven water, tidal wave, earthquake, drought, blizzard, pestilence, famine, fire, explosion, volcanic eruption, building collapse) that causes damage, ecological disruption, loss of human life or deterioration of health and health services on a scale sufficient to warrant an extraordinary response from outside the affected community or area.
- Hazard is any phenomenon which has the potential to cause disruption or damage to people & their environment.
Depending on their nature, disasters are classified as :
1. Natural disasters e.g.
- Tectonic: Earthquakes, tsunamis, and volcanic eruptions
- Meterological: Hurricanes, droughts, and floods
- Topological: Avalanches and landslides
2. Man-made disasters e.g.
- Chemical contamination
- Mass intoxication
- Mass accidents
- Victims of social violence
Disaster Cycle (Disaster Management)
There are following fundamental aspects of disaster management :
1. Disaster impact and response
2. Stage of health and medical relief
- Primary phase (0-6 hours) : First aid, medical care
- Secondary follow-up (6-24 hours) : Transportation, sanitation and immunization
- Tertiary clean up (1-60 days) : Food, clothing, shelter assistance, social service, employment, rehabilitation
- Water supply : Most practical and effective strategy of disease prevention and control in post-disaster phase is ‘supplying safe drinking water and proper disposal of excreta’.
- Sanitation and personal hygiene : Foremost step for disease prevention and control in post-disaster phase is chlorination of all water bodies. Level of residual chlorine to be maintained in all water bodies in post-disaster phase is > 0.7 mg/l (> 0.7 ppm).
- Food safety
- Vector control
4. Disease Mitigation : Measures designed either to prevent hazards from causing emergency or to lessen the likely effects of emergency. Most commonly reported disease in post-disaster phase is Gastroenteritis. A common micronutrient deficiency in disasters is Vitamin A deficiency: It occurs due to deficient relief diets, measles and diarrhea (gastroenteritis).
5. Disaster preparedness : Emergency preparedness is a programme of long term development activities whose goals are to strengthen the overall capacity & capability of a country to manage efficiently all types of emergency.