G. Sanitation and Environmental Health Services

Safe disposal of excreta is critical because agents of a large number of infectious diseases are passed from the body in excreta. These excreted infections fall into four main groups: viruses, bacteria, protozoa, and worms (helminths). Excreta, unless properly isolated, can also provide a breeding ground for insects, which may act as either direct or indirect transmitters of disease.

Links between diseases, infections, means of transmission, and the sanitation system must be kept under constant surveillance. But the links are not always the most obvious. For example, an important human link in transmission of an infection is the carrier who shows little or no sign of disease. Conversely, people in an advanced state of disease may have minimal impact on disease transmission, as those around them will be aware of the danger.

Human waste is more dangerous than animal waste; therefore, the safe disposal of human excreta is more important than the disposal of animal waste. Human feces are normally of much more concern than urine. In areas of Africa and the Middle East where the Schistosoma haematobium species of bilharzia exists, however, and in all areas where typhoid is common and endemic, proper disposal of urine is also extremely important.

a. Selection of a System-Immediate Considerations

The selection of an appropriate excreta disposal system requires consideration of a number of factors. In an emergency, however, time is the critical factor. Pollution of the environment by excreta, with all its attendant risks, cannot be stopped without immediate sanitation measures. Thus, the range of choices is always much more limited at the very outset of an emergency. Weeks or months cannot be lost in waiting for expert advice, construction to be completed, or material to arrive. In an emergency situation, provide systems to meet immediate needs, which can be improved or replaced later.

Emergency conditions may dictate at least the initial use of trench latrines. These can be dug quickly and need less space than individual family units. While very shallow trenches may be an initial quick solution, deeper trench latrines are much more effective. Where space and soil conditions allow, the simplest and most common individual family unit is the pit latrine.

Once a temporary system has been established, more time and care should be expended to establish the most appropriate waste disposal system. Two main factors will affect the choice of an excreta disposal system: the traditional sanitation practices of the displaced people and the physical characteristics of the area, including the geology, availability of water, rainfall, and drainage. Failure to take proper account of any of these factors can cause the system to rapidly become a health hazard. Above all, cleanliness of latrines and their ease of access will determine whether or not they are used.

First, it must be determined how the DPs can modify their traditional practices to reduce health hazards during the emergency situation. More than 40 percent of the world’s population does not have access to a sanitary form of excreta disposal. Traditional practices and other factors must be considered at the planning stage and will directly affect the type of system to be established. Other cultural factors to consider include:

• Previous sanitation system and practices.
• Method of anal cleansing.
• Preferred position (sitting or squatting).
• Need for privacy and security, particularly for women and children.
• Segregation of sexes and other groups or individuals with whom sharing a latrine is culturally unacceptable.
• Cultural practices for children.
• Cultural taboos (e.g., avoiding contact with anything that may have touched excreta of others).
• Social factors, including likelihood of community action to ensure proper use of proposed system.
• Cultural needs for special orientation (direction) of latrine.
• Systems used locally in neighborhood of site.

Arrangements must be made to ensure the availability of appropriate anal-cleansing materials and hand washing facilities at or near all latrines. Such facilities are essential for the maintenance of individual and community hygiene. Also, latrines must be safe for children and women and be accessible at night. For individual units, families may provide their own lamps, but some form of lighting should be provided for communal units. In some cases, guards may be needed near the latrines to ensure security.

b. Immediate Action

The first group of DPs arriving at a site should construct a disposal system adequate for their immediate needs. Without proper facilities, DPs are likely to defecate indiscriminately, contaminating their environment and possibly their water supply. In consultation with community leaders, the first step is to localize excreta; that is, control indiscriminate defecation. If space allows, designate an area or areas away and downwind from dwellings, but accessible and in close proximity. Fence the area(s), ensure privacy, and provide a shallow trench and spades, if possible. Locate these areas where surface runoff during rain will not cause contamination to the shelter area or water sources, and protect them with cutoff ditches.

A publicity campaign will be required to encourage the population to use specified areas and not defecate indiscriminately near dwellings. Measures must also be taken to prevent defecation or urination in or near the water supply. Immediate action in both regards can significantly reduce public health hazards.

If the ground is flooded or marshy or has a high water table, arrangements must be made as soon as possible to physically contain the excreta. Under such conditions, the location of the area, away from dwellings and the water source, is very important. Pending a proper containment system, a simple raised structure (e.g., a wooden stage some 50 cm high) can prevent the population from contaminating their environment with excreta. Empty 200-L (45-gal) oil drums can also be used if one end of the drum is cut out and then inserted open end down into a hole that is as deep as the water allows, with the last half meter of the drum left aboveground. A small hole should be cut into the aboveground end of the drum to transform it into a squatting plate. These options should be viewed as very short-term sanitation interventions.

In hot, dry climates where sufficient space is available, localized defecation areas located away from dwellings may be the best short-term arrangement, as heat and sunlight render the feces harmless with time. Black rock is the best surface. Under these conditions, potential health hazards in the area (e.g., an increased number of rats) should be periodically reviewed.

If the camp is on the coast, DPs may choose to defecate in the water. While this practice is less harmful than to indiscriminately defecate on land, it should be discouraged unless no other option is available. The dangers of defecating in the water increase greatly with numbers. Such practices contaminate the high-water line, and increase the health hazards of washing in the sea. Defecation in bays, estuaries, or lagoons where fish or shellfish are caught should be greatly discouraged, as this may be a source of infection in seafood.

c. Longer Term Options

For a number of reasons, expert advice is required to develop the most appropriate waste disposal system. The nature of the soil will be important; if the soil is highly impervious to water, some systems should be excluded from consideration. The availability of water and cultural considerations must also be considered. Many simple options, if properly constructed and maintained, will meet all public health requirements. In most emergencies, two main types of latrines are possible, even for DPs unaccustomed to them. The most common type is the dry latrine, such as a trench, pit, or hole in the ground. More elaborate pour-flush latrines use small quantities of water to flush wastes out of the toilet trap. Other systems are based on the composting of excreta.

d. Latrine Styles and Considerations

Three basic latrine styles are available: individual family units, centralized units with each latrine allocated to an individual family, and communal systems. Individual family units are the preferred solution, because people will always make more of an effort to clean their own latrine than they will to clean a communal facility.

To determine the most appropriate latrine style, consideration must be given to a number of factors, such as the number and siting of latrines, population density, soil, available water, drainage, and construction materials.

1. Number and Siting of Latrines
   • As a rule, at least one latrine (drop hole) should be provided for every 20 people. Latrines should be located at least 6 m from dwellings, 10 m from feeding and health centers, and at least 30 m from wells or other drinking-water sources. Although all these distances depend on latrine and soil type, latrines should be located no more than 50 m from users. If people must walk a considerable distance to a latrine, they will defecate in a more convenient location, regardless of the health hazard.
   • Even when in working order, latrines will not be used unless they are clean. Emergency conditions may dictate at least the initial use of trench latrines. The following standards for pit latrines are desirable.
   
   
   Facility	Standard
   Latrines, family	Not more than four families per latrine without organized, paid maintenance. Latrines should be located at least 6 m from dwellings, 10 m from feeding and health centers, and at least 30 m (and preferably farther) from wells or other drinking-water sources, but no more than 50 m from users.
   Trench latrines, shallow (for a few days)	30 cm wide by 1 m to 1.5 m deep by 3.5 m long per 100 people
   Trench latrines, deep (for a few months)	70 cm to 100 cm wide by 2 m to 2.75 m deep by 3.75 m long per 100 people

   
   
2. Population Density
   • Population density will affect the space available for the excreta disposal system and thus the type of system. If latrines are too close to dwellings, there may be insufficient space for individual units. Overcrowding may cause major health hazards and must be considered in site planning. The camp layout should be determined, among other things, by the needs of the most suitable sanitation system, not vice versa. Space must be available for replacement latrines where necessary.
3. Soil
   • Soil conditions can vary over a short distance of land, thus requiring a thorough survey of the area. The nature of the soil also may exclude certain options. For example, rocky soil may prevent the digging of pit-type systems. Sandy soil will demand special actions to prevent sidewall collapse of pits. Impervious clay soils may exclude any system dependent on seepage. Account should also be taken of the difference between dry-and wet-season soil conditions. If the ground freezes in winter, the choice of systems may be limited. Where a high water table exists, even only seasonally, care must be taken to ensure that the water is not contaminated by seepage from the latrines. Excreta must be contained in flood or swampy conditions.
4. Available Water
   • The amount of available water will determine whether disposal systems requiring water are a possibility. These systems are generally more expensive than those not requiring water. Because DPs’ situations are often characterized by a lack of reliable water sources, the excreta disposal system should not be dependent on water availability. Whatever the system, however, water should be available for anal cleansing and hand washing. The availability of water for hand washing is a critical consideration that should not be overlooked.
5. Drainage
   • Because all camps experience rain from time to time, anticipate where surface runoff will flow and how to divert it by cutoff ditches. The possibility of flooding should also be considered and drainage provided if necessary. If floodwater enters latrines, large areas may be contaminated.
6. Construction Materials
   • Construction material will be needed to build some types of disposal systems, for example, those with walls and roofs. DPs unaccustomed to latrines generally prefer a large enclosure with no roof. Strong arguments can be made, however, for covering latrines to prevent rainwater from filling the latrine and causing contamination around it or weakening the surroundings. Roofs should provide proper drainage away from the latrine. Special measures will be necessary to manufacture squatting or sitting slabs, water traps, and other equipment for pour-flush systems, if these are not available locally. Where DPs have an established method of covering latrines (e.g., with a wooden lattice), such techniques are generally preferred, even if these methods are more difficult to clean. A number of simple techniques exist for making special plates on site, for example, with reinforced cement and preformed molds. Local materials should be used for the structure as well as for reinforcing the pit where necessary. Above all, the latrine must be easy to clean, and the surfaces around the drop hole must be washable.

a. Wastewater (Greywater)

Excess water from washing, bathing, and food preparation is considered wastewater or greywater. It can be a problem if not drained away. Without good drainage, this water will collect in malodorous, stagnant pools that provide breeding places for insects, especially mosquitoes. Wastewater should generally not be permitted to enter latrines, as this will cause the latrine pit or trench to fill very quickly. If latrine pits or trenches are sufficiently large and the amount of water used for bathing is relatively small, however, DPs should be allowed to use the latrine area for bathing because it provides privacy and drainage. In most circumstances, separate bathing and clothes-washing areas with duck-boards or stones and proper drainage should be constructed.

b. Garbage

Because all communities generate garbage, established routines for the control, storage, collection, and disposal of solid wastes will be required. These needs must be reflected in initial site planning. If uncontrolled, the accumulation of garbage is both unpleasant and unhealthy. The potential for diseases transmission by rodent and insect vectors increases with improper garbage disposal. Free-range chickens, goats, and pigs will help control garbage; dogs will spread it.

The following suggestions for garbage storage, collection, and disposal are of particular concern for high-density camps, where the problem and dangers are greatest.

Storage. To store garbage, containers made of metal or plastic with a minimum capacity of 50 L should be provided. A 200-L oil drum cut in half is often used. Storage containers should have lids and drainage holes in the bottom. A ratio of 1 container per 10 families has proven to be effective. Containers should be placed throughout the camp so that no dwelling is located more than 15 m from a garbage container.

Collection. The collection of garbage from containers should take place on a regular, daily basis, if possible. Daily collection arrangements must be made to collect medical waste and wastes from feeding centers.

Disposal. Garbage can be disposed of by burying it at designated locations on the site or removing it from the site. Open dumping of garbage on site should be avoided. If garbage has to be dumped, it should be dumped far from the settlement areas. The ashes should be covered with a layer of soil after each burning.

The safe disposal of medical waste requires particular attention. Needles and scalpels are especially dangerous. Medical waste must be tightly controlled. It should be collected, transported, and disposed of separately. Medical waste should always be burned without delay. This disposal should be done in an incinerator to ensure high temperature and complete burning. Designated areas where medical waste and/or ashes are to be handled should be located far from dwellings and fenced to restrict access.

c. Dust

Large amounts of dust carried through the air can contaminate food and be harmful to human health by irritating eyes, the respiratory system, and skin. Dust can also harm some types of equipment used on site. The best preventive measure is to stop the destruction of vegetation on the site. Dust control can be achieved by spraying roads with water or oil, especially around health facilities and feeding centers, as well as limiting or banning traffic from certain areas.

DP camps are often overcrowded, are built of highly combustible shelter materials, and have many individual cooking fires. For these reasons, camps are very vulnerable to major fires. Measures to prevent and control fires must be considered from the start of emergency assistance at DP camps.

a. Prevention

The most basic and effective measure to prevent a major fire is the proper spacing and arrangement of all buildings to provide firebreaks. Other measures include allowing individual fires for cooking only and building fires outdoors only, if possible. If cooking must take place indoors, and especially in wooden or wattle-and-daub buildings, the cooking area should be protected with fire-resistant sheeting if possible. If large-scale cooking takes place indoors (e.g., in a supplementary feeding center), fire-resistant ceilings and walls are mandatory. Fire retardants can be applied to thatched roofs in dwellings. Proper precaution must be taken when storing and using fuels. Highly flammable synthetic materials should be avoided.

b. Control

When fighting a large fire with scarce resources, the first priority is to contain it, rather than put it out. Fires can be controlled in the first few minutes with modest resources, providing quick action is taken. To control fires, an alarm system, firefighting teams, and beaters must be organized in advance and plans prepared. Water is generally not available in sufficient quantities or at adequate pressure for the control of major fires; however, sand or other loose mineral soil material can be an effective method of control. A new fire-break should be created by taking structures down manually or with a bulldozer if available.