Friday, July 27, 2012

THE ROLES OF ENVIRONMENTAL HEALTH OFFICERS IN DISASTERS AND EMERGENCY SITUATIONS

By Augustine Ebiske, Registrar, Environmental Health Officers Registration Council of Nigeria [EHORECON] At the 43rd Annual Conference/Scientific of Workshop organized by Environmental Health officers Association of Nigeria [EHOAN] in 12th October, 2010, Minna

Opening:
This presentation has been adapted from WHO book “Environmental health in
emergencies and disasters” A PRACTICAL GUIDE Edited by B. Wisner, J. Adams
(2002).

INTRODUCTION:
To be able to discuss this paper better, I will start from the meaning of the key words. According to (Wikipedia 2010), a disaster is a perceived tragedy, being either a natural calamity or man-made catastrophe. It is a hazard which has come to fruition. A hazard, in turn, is a situation which poses a level of threat to life, health, property, or that may deleteriously affect society or an environment.

In contemporary academia, disasters are seen as the consequence of inappropriately managed risk. These risks are the product of hazards and vulnerability. Hazards that strike in areas with low vulnerability are not considered a disaster, as is the case in uninhabited regions.

Furthermore, the word Disaster derives from Middle French word d├ęsastre and that from Old Italian word disastro, which in turn comes from the Greek word prefix 5ua-, (dus-) “bad”+ ╬«(aster), “star”. The root of the word disaster (“bad star” in Greek) comes from an astrological theme in which the ancients used to refer to the destruction or deconstruction of a star as a disaster.
According to (WHO 2002), Disasters are events that occur when significant numbers of people are exposed to extreme events to which they are vulnerable, with resulting injury and loss of life, often combined with damage to property and livelihoods.

Disasters, commonly leading to emergency situations, occur in diverse situations in all parts of the world, in both sparsely populated rural and densely populated urban regions, as well as in situations involving natural and man-made hazards. Disasters are often classified according to their speed of onset (sudden or slow), their cause (natural or man-made), or their scale (major or minor). Various international and national agencies that keep track of disasters employ definitions that involve the minimum number of casualties, the monetary value of property lost, etc.

The forces that bring vulnerable people and natural hazards together are often man made (conflict, economic development, overpopulation, etc) Some of the most serious disasters and emergencies are created or further complicated by conflict and the forced movement of large numbers of people.

One way in which disasters may cause, or worsen, emergency situations is through the damage they do to environmental health facilities and services.

The common effects of various natural disasters on environmental health services.

Flooding, power failures, broken pipes and blocked roads can all disrupt water, waste and food-handling services for hours or days. More severe damage to civil
engineering structures, from bridges to water mains, can cause disruptions lasting days or weeks. In aH such cases, contingency plans for temporary repairs and, when necessary, alternative water supplies and sanitation arrangements are required.

Some key words (as defined by WHO)
Disasters are events that occur when significant numbers of people are exposed to hazards to which they are vulnerable, with resulting injury and loss of life, often combined with damage to property and livelihoods.

Emergencies are situations that arise out of disasters, in which the affected community’s ability to cope has been overwhelmed, and where rapid and effective action is required to prevent further loss of life and livelihood.

Emergency planning is a process that consists of: determining the response and recovery strategies to be implemented during and after emergencies (based on assessment of vulnerability); responsibility for the strategies; the management structure required for an emergency; the resource management requirements.

Emergency preparedness is a programme of long-term development activities whose goals are to strengthen the overall capacity and capability of a country to manage efficiently all types of emergency and to bring about an orderly transition from relief through recovery and back to sustained development.
Emergency prevention is based on vulnerability assessment and concerns the technical and organizational means of reducing the probability or consequences of disasters and the community’s vulnerability.

Environmental health management is the intentional modification of the natural and built environment in order to reduce risks to human health or to provide opportunities to improve health.

Environmental health and disasters
Environmental health hazards and threats to human health from exposure to disease causing agents are closely associated with disasters and emergencies in a variety of ways. Some disasters may involve extreme events that affect a vulnerable population directly, such that their livelihoods and lifelines that support their basic needs are disrupted for a significant period of time. However, the disruption of livelihoods may also be indirect and, even though an emergency situation may not develop, people’s vulnerability to future disasters can be increased. An explosion and lire in an industrial quarter of a city might not kill or injure anyone directly, but the employment and income of large numbers of workers and their families may be interrupted. Indirectly, then, there may be an additional threat to the satisfaction of basic needs, since the unemployed workers may not be able to afford an adequate diet, pay rent or pay for health care.

These are precisely the kinds of circumstances that can increase a family’s vulnerability to future disasters.

A broad range of activities can be designed to enable the health sector to prevent, mitigate and respond to such hazards. Disasters and development are connected in ways that necessarily involve the contributions of environmental health professionals. Through better education and higher incomes, development can improve people’s capacity to cope with environmental health hazards. On the other hand, certain types of development can create new hazards or new groups of people vulnerable to them. Disasters can set back development, but they can also provide new development opportunities. strategic planning to increase the capacity of people to withstand disaster hazards must therefore include concerns for environmental health.

Environmental health activities are interdisciplinary, involving engineering, health sciences, chemistry and biology, together with a variety of social, management arid information sciences. In limes of disaster and recovery, people from many backgrounds engage in activities designed to monitor, restore and maintain public health. Likewise, health workers find themselves cooperating with others to help with non-health-related work, such as search-and-rescue, or work that is only indirectly related to health, such as public education.

Hazards and extreme events
A hazard is any phenomenon that has the potential to cause disruption or damage to humans and their environment. Hazards are the potential for an event, not the event itself. Extreme events are natural’ or man-made processes operating at the extremes of their range of energy, productivity, etc. For example, mudslides, floods, coastal storms, locust or rat invasions are all natural, but extreme events, and to some extent the likelihood of them occurring, may be estimated. Many extreme events, such as severe floods, have been monitored and recorded over many years and have a known probability of occurrence. Man-made hazards, such as the potential for leaks of dangerous chemicals or radiation, also exist and many so-called natural hazards become events or are exacerbated by human activity. For instance, flooding in Bangladesh during the 1990s was made worse because large numbers of discarded plastic bags blocked drainage systems. Extreme events create stress in human systems and structures because the forces involved are greater than those with which the systems and structures normally cope. For instance, all houses will withstand some wind, but beyond a certain wind speed all will fail. Many farming communities are able to cope with mild and occasional drought, but are overwhelmed by severe and repeated drought. Extreme events often occur in complex “cascades”. Earthquakes may trigger mud or rock slides. Debris may dam a river, producing an artificial lake that threatens downstream settlements with flooding if the dam is breached. Forest fires can produce barren slopes more prone to erosion and flash flooding. Earthquakes may cause electrical fires or explosions of natural gas. Where urban water supplies are stored in reservoirs, earthquakes can damage them, causing flooding and reducing the quantity of water available to fight fires.

The statistical probabilities of such extreme events occurring can be estimated with different degrees of confidence. Some events, such as floods and cyclones, are clustered seasonally. The recurrence of major rainfall and floods can be calculated, but specific floods are harder to predict.

Some natural events, such as the emergence of a fatal cloud of carbon dioxide and hydrogen sulphide from the depths of Lake Nyos in Cameroon in August 1986, are unexpected and are not amenable to preparedness measures.

Disasters are events that occur when significant numbers of people are exposed to extreme events to which they are vulnerable, with resulting injury and loss of life, often combined with damage to property and livelihoods.

Disasters, commonly leading, to emergency situations, occur In diverse situations in all parts of the world, in both sparsely populated rural and densely populated urban regions, as well as in situations involving natural and man-made hazards. Disasters are often classified according to their speed of onset (sudden or slow), their cause (natural or man-made), or their scale (major or minor). Various international and national agencies that keep track of disasters employ definitions that involve the minimum number of casualties, the monetary value of property lost, etc. Other definitions are used by countries for legal or diplomatic purposes, e.g. in deciding when to officially declare a region a “disaster area”. The terminology used here is less precise so as to co a broad range of situations. The forces that bring vulnerable people and natural -hazards to are often man-made (conflict, economic development, overpopulation, etc.)..

An example of natural and technological hazards combining in surprising ways was seen in Egypt in 1994. Heavy rain near the town of Dronka weakened railway lines.

A train carrying fuel was derailed and leaking fuel was ignited by electrical cables, causing an explosion. Finally, burning fuel was carried by flood waters through the town, killing hundreds of people (Parker & Mitchell, 1995).

Conflict
Some of the most serious disasters and emergencies are created or further complicated by conflict and the forced movement Of large numbers of people. Conflict is a major cause of direct and indirect land degradation, leading to greater risk of environmental disasters, and also consumes resources that could be used by society to reduce vulnerability to extremes in natural and technological hazards. Conflict also imposes the greatest demands on environmental health personnel, equipment, supplies and supporting service thus calling for the most skilful use of relief resources. The secondary impact of conflict, in terms of the public health problems it creates and the disruption of environmental health services it causes, are of major importance.
Volcanic
Common levels of impact of natural disasters on environmental health services
Most common effects on environmental health

Earthquake a Cyclone b Flood c Tsunami d Volcanic eruption
e



Water supply and wastewater disposal Damage to civil engineering structures 1 1 1 3 1
Broken mains 1 2 2 1 1
Damage to water sources 1 2 2 3 1
Power outages 1 1 2 2 1
Contamination (biological or chemical) 2 1 1 1 1
Transportation failures 1 1 1 2 1
Personnel shortages 1 2 2 3 1
System overload (due to population shifts) 3 1 1 3 1

Solid waste handling Equipment, parts and supply shortages 1 1 1 2 1
Damage to civil engineering structures 1 2 2 3 1
Transportation failures 1 1 1 2 1
Equipment shortages 1 1 1 2 1
Personnel shortages 1 1 1 3 1
Water, soil, and air pollution 1 1 1 2 1


Food handling Spoilage of refrigerated foods 1 1 2 3 1
Damage of food preparation facilities 1 1 2 3 1
Transportation failures 1 1 1 2 1
Power outages 1 1 1 3 1
Flood of facilities 3 1 1 1 3
Contamination/degradation of relief supplies 2 1 1 2 1



Vector control Proliferation of vector breeding sites 1 1 1 1 3
Increase in human/vector contacts 1 1 1 2 1
Disruption of vector-born disease control programmes 1 1 1 1 1
Home sanitation Destruction or damage to structures 1 1 1 1 1
Contamination of water and food 2 2 1 2 1
Disruption of power, heating fuel, water supply or waste disposal services 1 1 1 2 1
Overcrowding 3 3 3 3 2

KEY
I - Severe i,ossihle effect.
2 - Less severe possible effect.
3 - Least Of III Possible effect.

The effects of disasters on environmental health facilities and services

One way in which disasters may cause, or worsen, emergency situations is through the damage they do to environmental health facilities and services. See summary above. -

Flooding, power failures, broken pipes and blocked roads can all disrupt water, waste and food-handling services for hours or days. More severe damage to civil engineering structures, from bridges to water mains, can cause disruptions lasting days or weeks. In all such cases, contingency plans for temporary repairs and, when necessary, alternative water supplies and sanitation arrangements are required.

Transportation difficulties and shortage of personnel may cause disruption of vector control programmes, some conditions, such as flooding, may result in the proliferation of vector breeding sites which local vector-control programmes cannot deal with. Droughts may produce a series of problems for water-supply and sewage-. Treatment systems as a result of low flow from intakes end clogging of intakes; and electricity supplies may be unreliable if power generation is affected.

Emergencies
An emergency is a situation or state characterized by a clear and marked reduction in the abilities of people to sustain their normal living conditions, with resulting damage or risks to health, life and livelihoods. Disasters commonly cause emergency situations, both directly and indirectly. Evacuation or other necessary steps taken to avoid or flee from a disaster, for example, can cause disruption of normal life on a scale calling for emergency action. Sudden, large-scale movements of people within and between countries often produce emergency conditions. Dramatic loss of livelihoods and increased spending needs due to drought or flooding may place people in a very vulnerable situation.

A cholera epidemic may overwhelm the capacity of a city’s under-resourced health service, creating an urgent need for support. In such emergency situations, local coping mechanisms are overwhelmed and so collective, specialized and often external action is required. During an emergency, it is common to see primary effects of the disaster followed by secondary effects. For instance, the primary effect of a mudslide might be that many people are injured and need urgent medical attention. A secondary effect might be that blocked sewers and broken water mains lead to an outbreak of water- and sanitation related disease some weeks later, or that the loss of livelihoods through the destruction of vegetable gardens and workshops leads to reduced food intake and a nutrition emergency some months later. Human needs for non-material things, such as security and cultural identity can also be affected, and the psychological and social impacts of a disaster may be felt many years after the event.

Emergency situations are often described in public health terms, with the crude mortality rate (CMR) being widely accepted as a global measure of their severity. A CMR which is significantly higher than the rate in the affected population before the disaster, or which is above I death per 10 000 population per day (or 3 deaths per 1000 population per month) indicates an emergency situation.

CMRs in the emergency phase following various types of disaster may be many times the background rate for the region or the affected population. Many more deaths may occur during the post-disaster emergency phase than as a direct result of the disaster itself. However, mortality rates are trailing indicators that do not indicate problems before people die as a result of them, and do not indicate the nature of the problems. Therefore, other indicators concerning health, environmental, social and economic factors are important for understanding the nature of the emergency and how it is likely to change over time, and for understanding how to react effectively.

The term complex emergencies is used to describe situations of disrupted livelihoods and threats to life produced by warfare, civil disturbance and large-scale movements of people, in which any emergency response has to be conducted in a difficult political and security environment. A combination of complex disasters and natural hazards (e.g. Military and political problems combined with severe winter weather, coastal storms and flooding, drought and a cholera epidemic) was particularly devastating in the 1990s in such countries as Bosnia and Herzegovina, Iraq, Myanmar, Peru and Somalia.

Role of Environmental Health Officers In Disasters and Emergencies

From the presentation so far, we have seen what gets compromised in emergencies and disasters, As Environmental Health Officers our roles in these situations starts from the time before the disaster occurs.

Hazard mapping
The average frequency of occurrence and location of most extreme events can be determined with some degree of accuracy. While global maps of hazards, such as potential desertification, severe storms, and earthquake and volcanic activity, do exist a more detailed approach is of more use to environmental health and disaster planners. Historical records; physical data and computer simulations allow the production of detailed city, sub-national or national maps overlaid with zones of probable physical damage from such extreme events as landslides, floods, earthquakes, volcanic eruptions, storm surges and tsunamis.
The same approach can be taken with industrial accidents. Maps of the zones surrounding hazardous factories and (he routes used to transport hazardous materials, plus data on seasonal wind velocity and direction, can be used to predict the scale of possible hazards and determine the method of evacuation or other emergency response if leaks or explosions occur. Public and private records of past industrial activity can be a valuable resource for identifying the presence of physical hazards.

The survey should be organized by geographical region and should also profile the vulnerability of different ethnic and socioeconomic groups, Disparities and priority needs in such areas as water supply, drainage, sanitation, refuse and waste disposal, housing, and food hygiene should be documented. The prevalence of vector-borne and contagious diseases by region and by socioeconomic group should also be integrated into comprehensive risk planning.

Finally, the location and safety of industrial facilities in relation to settlements should be reviewed from the point of view of air, soil and water contamination, as well as the risk of radiation, fire, explosion and accidental poisonous emissions. Such baseline surveys can reveal who is more likely to suffer from an emergency directly related to environmental health as well as where this is most likely to occur.

Warning indicators
Early warnings
An extremely important component of preparedness, prevention and mitigation is the capacity to obtain and use early warnings of impending hazards or threats. There are limitations and obstacles to the timely forecast of extreme events, however, and a number of factors can also limit the effectiveness of warnings in influencing public behaviour. Both sets of constraints must be borne in mind by environmental health managers. Warning systems vary greatly, as does the amount of forewarning that they give. Warnings must give sufficient time to enable environmental health preparedness and prevention activities to be carried out.

Stow-onset hazards
In the case of slow-onset hazards, such as drought and certain outbreaks of plant, animal and human disease, there is often a tong warning time. Meteorological services are increasingly capable of reliable forecasts of climate patterns several

Environmental health indicators, in combination with routine activities carried out by veterinarians nutritionists and epidemiologists, can be used to provide early warnings of some of these slow-onset hazards. Some African countries have systems for early warning of famine, which are linked to nutrition surveillance. In Botswana, for example, monthly returns from weighing and measuring children in well-baby clinics are automatically screened for anomalies. These data, together with crop and livestock data, are used to trigger a variety of timely drought-response measures, including supplementary feeding, public works as a form of income supplement and the exemption of affected families from paying taxes.

Hazards with moderate warning time
A number of hazards, have an intermediate range of warning times. Those responsible for environmental health should be among the first to be informed by the authority issuing the alert or provisional warning, in advance of any public announcement. An effective communication system should be established and the readiness of supplies, equipment, transport, communications and personnel should be confirmed. There may also be specific actions that managers can take to increase the level of protection of vital facilities or to prepare for possible evacuation. For instance, a volcanic eruption can usually be foreseen by a few days, if not as long as a few weeks or even months in advance, and the affected population can be evacuated in good time. Ash fall from volcanoes can contaminate and clog water- storage facilities and treatment plants and, with sufficient warning, steps can be taken to protect water supplies from this hazard.

Warning of industrial accidents
Advance warnings of large-scale accidents in industry, transportation, etc., are limited by the nature of the events concerned. For example, in Bhopal, India, there was no advance warning of the cloud of methyl cyanide that descended on the residents. In the case of the explosions in the sewer system of Mexico’s second largest city, Guadalajara, in 1992, citizens had been complaining for several days to the authorities about the smell of petrol. Frequent inspections of high-risk factories and, for example, bridges and dams can reveal structural weaknesses.

Warning of refugee movements
Civil unrest or war in one country should alert the relevant authorities of neighboring countries that an influx of refugees is possible. Several weeks’ or even months’ warning may be provided. Arrangements can then be made to receive and accommodate refugees, especially where there has been a prior history of cross- border movements and where food, medical supplies, blankets and tents or tarpaulins have been stockpiled.

After the Disaster:23
After all the planning, and finally the disaster occur, there is need for environmental health intervention and support. This will be needed in the areas of food supply, housing, drinking water, sewage disposal.

Short-term shelter in existing buildings
In many situations, people may independently seek shelter in buildings such as schools, community centres, offices, sports facilities, and even railway carriages and wagons. Such buildings are often also used for organized short-term evacuation centres The evacuation centre should be as close as possible to the neighborhood or rural community concerned but far enough from the disaster site to avoid secondary hazards. This avoids the additional stress and health dangers of a long journey, and enables survivors to have access to their former dwellings, which is psychologically important. Buildings used as short-term reception areas should be thoroughly inspected by a suitably qualified person, to ensure that they are not structurally damaged, or sited near potential secondary hazards.

Such buildings will probably have at least some running water and toilets, and some may even have kitchens. For large numbers of people, however, these will have to be supplemented. Military barracks or youth camps are usually better equipped for large numbers of people, but have the disadvantage of often being sited further away from population centres. Whatever the buildings used as temporary accommodation, it is very important that they are only used for a short period, and that they are cleaned and maintained intensively, to avoid a rapid deterioration in environmental health conditions.

• People sleeping on beds or mats should have a minimum of 3.5m2 of floor area or 10m3 of air space, In rooms with high ceilings, double bunk beds may be used.
• Beds or mats should be separated by a minimum distance of 0.75 metres.
• Adequate ventilation is required. The amount of fresh air needed is approximately 20—30m3 per person per hour. It may be necessary to provide mechanical ventilation. Whenever possible, smoking and the use of cooking fires in the shelter should be strongly discouraged.
• An ambient temperature of I 5—I 9 °C is desirable, but lower temperatures can be tolerated with warm clothing, In cold climates, buildings may need extensive repairs and modificatiohs for winter conditions, particularly in conflict situations here windows and insulation material may have been removed or destroyed.
• To avoid very high temperatures in hot climates, buildings can be modified to increase shade, ventilation and thermal capacity.
• Buildings should have emergency exits and fire escapes; the flues of stoves used for space heating should extend outside the building; overloading of electrical circuits should be avoided; lanterns and lamps should be placed or suspended so as to avoid dangers; and liquid fuels should be stored outside the building. Clear instructions on fire hazards and safety practices should be displayed in conspicuous places and drawn to the attention of residents, fire-fighting equipment should be available and properly maintained. A group of volunteers from among the survivors should be taught about the possible fire hazards and trained in the use of fire-fighting equipment.
• Access to sufficient water for drinking, cooking, and personal and domestic hygiene should be provided.
• One wash basin should be provided for every 10 people or 4—5 metres of wash bench for every 100 people; there should be separate benches for men and women, and waste receptacles at each bench. One shower head is needed for every 50 people in temperate climates and one for every 30 people in hot climates. Floors must be disinfected daily.
• Arrangements must be made for human waste disposal. Water-flushed toilets may be available in existing buildings if the water supply has not been interrupted.

Outside latrines should be located within 50 metres of the building, but at least 20 metres away from the kitchen, dining hall and water supply.
One refuse bin of capacity 50—1 00 litres should be provided for every 12—15 people. The bins should have tightly fitting lids. Special arrangements for the
collection of refuse may be needed if the normal collection service is interrupted.
Site selection and arrangement of emergency settlements

When existing buildingsare not vailable, one possibility is to use tents or makeshift shelters made of plastic sheets, tarpaulins, or local materials, such as palm thatch, in a secure location where water, sanitation and food can be provided. Emergency settlements for refugees and displaced people need to be established rapidly. However, they may be in service for months or even years, and it is usually impossible to know at the outset of an emergency how long the emergency settlement will exist. Therefore, the measures listed below are designed to provide healthy living conditions for disaster-affected people in both the short term and the long term.

The requirements that ensure that temporary camps are healthy environments are considered below
• The site should be free of major water-related hazards such as malaria, onchocerciasis (river blindness), schistosomiasis (bilharzia) and trypanosomiasis (sleeping sickness). If these diseases are endemic, care shou!d be taken to avoid or control vector habitats and provide persona! protection against mosquitoes, black flies, tsetse flies, etc.
• The topography of the land should permit easy drainage and the site should be located above flood level. Rocky, impermeable soil should be avoided. Land covered with grass will prevent dust, but bushes and excessive vegetation can harbour insects, rodents, reptiles, etc., and should be avoided or cleared. Wherever possible, steep slopes, narrow valleys, and ravines should be avoided. Ideally, the site should have a slope of 2—4% for good drainage, and not more than 10% to avoid erosion and the need for expensive earth-moving for roads and building construction.
• Whenever possible, the area should be naturally protected from adverse weather conditions.
• Areas adjacent to commercial and industrial zones, exposed to noise, odours, air pollution and other nuisances should be avoided.
• Areas sufficiently close to blocks or rows of shelters should be identified for sanitation and waste management. The residential area of the camp should face the prevailing wind to avoid odours from latrines.
• There should be ample space for the people to be sheltered and for all the necessary public facilities such as roads, firebreaks (areas without buildings and with little or no flammable vegetation) and service areas (30m2 per person, or 45m2 per person allowing for small gardens, but not for full-scale agricultural activities). Areas for public spaces, markets, etc. should be defined from the beginning.
• Food distribution areas should be organized so as to create safe conditions for people collecting food, as well as for those distributing it.
• To facilitate the management and control of communicable diseases, camps should hold no more than 10000—12000 people or should be subdivided into independent units of no more than 1000 people.
• Drainage ditches should be dug around the tents or other shelters and along the sides of roads, especially if there is a danger of flooding. Care should be taken to lead water away from shelters, latrines, health centres, and stores. Persistent areas of stagnant water that are difficult to drain can be backfilled, or covered with polystyrene balls or a thin layer of oil, to control insects. Water points should also have adequate drainage to avoid mud.
• The site should be provided with at least two access roads for reasons of security and to reduce the risk of the site being cut off due to floods or other problems with roads.
• The surface of roads can be sprinkled with water to keep dust down. Sullage wastewater can sometimes be used to keep down dust on dirt or gravel roads. Restricting traffic and imposing speed limits can also help to reduce dust.
• Shelters should be arranged in rows or in clusters of 10—i 2 on both sides of a road at least 10 metres wide to permit easy traffic flow and access by ambulances or fire fighting vehicles. In tented areas, there should be at least 2 metres between the edge of the road and the tent pegs.
• Built-up areas should be divided by 30 metres wide firebreaks approximately every 300 metres. Firebreaks can be used for locating roads and recreation areas.
• Shelters should be spaced 8 metres apart so that people can pass freely between them without being obstructed by pegs and ropes. This spacing also helps to prevent the spread of fire, If this is riot possible owing to a lack of space, the distance between shelters should preferably be at least twice the overall height of each shelter, and should never be less than 2 metres. A separation greater than 8 metres may lead to open defecation and should be avoided.
• There should be a minimum of 3.5m2 per person inside the shelter in warm climates where cooking is done outside, and, 4.5—5.5m2 per person in cold climates where cooking is done inside the shelter.
• Shelters may be tents or prefabricated units or may be built out of plastic sheeting together with timber, stone and thatch. Where plastic sheeting is used, it is common to provide one piece, 4 metres by 6—7 metres, per household.
• Small shelters with few occupants are preferable to large shelters with many occupants.
• In cold weather, kerosene stoves or other heating appliances should be provided and people should be instructed in their use; every precaution must be taken to prevent fires and explosions.
• In the absence of electric lighting, wind-proof kerosene or oil lamps, or battery operated lanterns, should be provided for lighting shelters, toilets and roads.
• Natural ventilation should normally be adequate for temporary shelters such as tents.
• The site chosen should be within reasonable distance of an ample source of good water and, ideally, near some high ground from which water can be distributed by gravity; water sources should gradually be improved and protected once basic needs are satisfied. No one should have to walk more than 500 metres to a water point, and there should be at least one water point for every 250 people.
• Where there is no piped water, water tanks should be installed on both sides of the road.
• Refuse bins should be provided
• Latrines or other facilities for excreta disposal should be provided (at least one toilet per 20 people) and gradually improved as time and resources allow. The dangers of indiscriminate defecation should be emphasized in health education. Maintenance of toilets must be given priority in health education and camp organization.
• Bathing, laundry and disinfection facilities should be provided, and health education should emphasize the importance of frequent hand-washing. One double sided ablution bench (3 metres long) should be provided for every 50 people.
• The camp site should be cleaned regularly according to a prearranged schedule. Participation by camp residents in the cleaning of the camp should be encouraged. Young residents can be organized into teams responsible for cleaning and reporting possible health and environment problems.
• Separate accommodation is necessary for unaccompanied children, with provision for adults (welfare staff and/or community volunteers) to stay with them; there should be at least one adult per shelter or room. These children may be very disoriented and frightened, and array also have special nutritional needs. The shelters should be situated near the nutritional rehabilitation centre and field hospital, and as far from sources of secondary hazards, noise and contamination as possible.
• In conflict- and famine-related disasters, many people may be suffering from malnutrition and debilitation when they arrive, so specialized services such as intensive or therapeutic feeding may be needed. Intensive feeding or nutrition rehabilitation units should be provided with up to 15—30 litres of potable water per bed per day. Also, special care needs to be given to latrines and other waste disposal facilities used by parents, children and staff. Means for hand-washing by all staff and parents concerned with child feeding are also important.

Conclusion:
In conclusion, Environmental Health Officers have a great role to play in Disaster and Emergencies both before such situations arise and its long term management. It is for us as professionals to ensure that we stand up to the challenge faces by both disaster and Emergency situations.

References
Environmental health in emergencies and disasters” A PRACTICAL GUIDE (WHO
2002) edited by B. Wisner, J. Adams (2002).