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Environmental_Health_and_Sanitation_Part_1_Sibande.ppt
- 1. ENVIROMENTAL HEALTH AND SANITATION(PART 1) Presented By G. C. Sibande MPH, RNM
- 2. Objectives • Describe environment •Describe components of the environment that influence health • Describe the following components of environmental health: Sewage disposal Refuse disposal Pest/ vector and pest/ vector control
- 3. Introduction • This unitfocuses on environmental health issues that influence the health of individuals, families and communities. • Environment is the collective term used to describe all the living and non-living things that make up our surroundings. • These include the biological, technological, physical, cultural, social, economic and political aspects.
- 4. Components of theenvironment • The physical environment consists of air, water, soil, climate and other physical conditions. • Biological environment includes living things like the plants, animals and microorganisms. These also influence the health of the people. • The social, technological and political environments are man made e.g. The family, village, culture, beliefs, industries, politics and the government.
- 5. Description of theenvironmental health • Environmental health encompasses all elements of the environment that influence people’s health and well being. • It is concerned with assessing, controlling and improving the impact people make on their environment and the impact of the environment on people. • The health, and even the survival of man depends on his ability to adjust or adapt to the environment.
- 6. Cont... • Activities aimedat improving the quality of the environment and reducing the amount of disease is known as environmental sanitation • It is one of the most important aspects of primary prevention. • Therefore it is the responsibility of all health workers to help improve the environment.
- 7.
- 8. Objectives • Define sewageand sewage disposal • Explain how excreta is disposed Describe different types of latrines Describe a water carriage system Explain how the sewage system works
- 9. Sewage • Sewage iswaste material comprised of faecal matter, urine, vomits, sullage from personal washing, laundry, food preparation, the cleaning of kitchen utensils, industrial and agricultural wastes that is carried away in water from homes and buildings in a system of pipes
- 10. Sewage disposal • Propersewage disposal directly involves disposal of human excreta and watery wastes through latrines and water carriage systems • Hygienic disposal of excreta forms the basis of good hygiene in any household • Prevents bad odour and presence of flies • Prevents the spread of diseases directly or indirectly through the 4 F connections - diseases such as Typhoid, cholera, Hepatitis A, dysentery e.t.c.
- 11. The 4 Fconnections FLIES FOOD FAECES FINGERS
- 12. Latrines • A commonmethod of excreta disposal in rural areas is the pit latrine. • A pit latrine consists of a hole in the ground, a squatting plate (on which to squat) when defecating or urinating.
- 13. Types of latrines Pitlatrine • Traditional pit latrine • San- plat (Sanitation Platform) – squatting slab structurally safe, footrest - good for easy positioning to reduce fouling, hole too small for child to fall in, cement floor – easy to clean, some fly control with tight fitting lid • VIP (ventilated improved pit) It has a black vent pipe fitted to the pit and a fly screen at the top outlet of the pipe – eliminates odour and flies through air circulation • Composting latrine Bucket latrine
- 14. Pit latrine Construction considerations: •Pit latrine should be on dry ground where water drains away, and with a surrounding storm-water drain. • The soil must be porous to allow the liquid to drain away • A pit latrine should be situated 15 meters away from the water source if on the same level or below the source, or more than 30 meters if the latrine is above the water source.
- 15. Pit latrine contd •Must be fly proof - pit must be 3.5 - 5 metres deep. (10 feet deep) covered with concrete platform or skilfully constructed floor with local materials • Have a reasonable cover over the hole • It should have a pipe which goes deep into the hole and out over the roof to remove odour
- 16. Pit latrine contd Advantages •Best for rural areas with no piped water • It has an initial financial outlay but low running cost • Has long life span -bacteria act on the faeces and convert the solid into liquid. • It can be accessible to the local community • It is suitable for mass usage
- 17. Pit latrine contd •Faeces need no further handling after disposal Care: • The cement platform must be cleaned daily • If the platform is constructed with mud, smear at least one a week and sweep daily • The hole should be covered with a fitting cover to prevent odour and flies.
- 18. Bucket latrine • Abucket receives the excreta • Commonly used in town with no adequate water carriage system • Expensive to run • Has to be emptied every night • Difficult to find workers for this type of job
- 19. Flush toilet/ watercloset • The most hygienic way of dealing with foul liquid waste and human excreta when properly used. • Flush toilets need a permanent, continuous and adequate piped-water supply to work efficiently • Any failure of the water supply makes them unhygienic to use. • Drains and sewers collect the sewage • Their construction is more complicated and expensive, and can only be done by trained workers.
- 20. Water carriage system Thereare two types of water carriage systems: • Small scale systems- Water closet (flush lavatory) connected to a septic tank- this is ideal for a house, health centre or small school • Larger systems- Water closet (flush lavatory) with direct sewer connection where sewage ponds or lagoons are used and are sited some distance away from buildings in the open air, also biological action takes place. Mostly used in urban centres.
- 21. Water closet • Consistsof: • Porcelain pan with a seat • 5 litres flushing cistern which empties the pan of water and excreta • S – shaped bend – acts as a trap, with a water seal to prevent bad odours coming from the waste pipe • Connecting pipe, soil pipe and inspection chamber • House drain leading to a sewer or septic tank
- 22. Septic tank • Idealfor isolated buildings and institutions where there is no sewer • Sewage is retained for days • Heavy sediments settle as sludge • Effluent escapes through the outlet pipe and soak away pit. • Bacteria and fungus make the sewage sludge and effluent harmless • The tank has to be emptied of sludge regularly • The tank is sunk below the ground and should always covered.
- 23. Septic tank contd Advantages: •minimal running costs • Waste matter not handled • Waste matter is inaccessible • No disease risk • No odour if properly constructed
- 24. Septic tank contd Disadvantages •Initial outlay expensive • May smell if poorly constructed • Emptying becomes expensive
- 25. Sewage works disposal •Sewage may be pumped out to sea in coastal areas but is not advisable. Alternatively, biological method is used as follows: • Sewage is passed through a grid to remove paper. • Sand and grit are removed next then sedimentation occurs. • The sewage moves to the settling tanks where solid sludge forms.
- 26. Sewage works disposalcontd • The effluent (top fluid) becomes harmless by exposure to the air and bacteria. • The harmless fluid is drained into rivers or lakes. • The sludge is removed, treated dried and sold as manure
- 27. Role of communityhealth nurse • Individual and population risk assessment • Risk communication • Community involvement • Epidemiologic investigation • Advocate for policy development
- 28. REFUSE AND REFUSEDISPOSAL
- 29. Objectives • Define refuse •Describe types of solid waste • Describe sources of solid waste • Explain importance of proper waste disposal • Describe disposal methods • Discuss health care waste management
- 30. Definition • Refuse orsolid waste is anything that needs to be disposed off or thrown away. • Refuse or solid waste is considered as something which is no longer wanted in a given place and time.
- 31. Types of solidwaste • General waste - municipal waste or non- hazardous waste • Hazardous waste – one that poses substantial potential hazard to human health or living organisms
- 32. Sources of solidwaste • Residential/domestic - left over foods, waste paper, plastic bags • Commercial • Institutional • Industrial • Agricultural • Construction and demolition • Municipal services e.g. street sweeping, street- wrecks of cars, plastics and papers
- 33. Importance of properwaste disposal • Rotting, decaying organic matter attracts insects and vermin and cause fly breeding places. • Collection of stagnant water in cans, bottles and tyres provide breeding places for mosquitoes. • Decaying refuse has a bad odour – air pollution • Children may injure themselves on broken bottles • Can cause fires
- 34. Importance of properwaste disposal contd • Ground and surface water supplies may be polluted by accumulated refuse especially in wet season. • Industrial waste contain harmful chemicals which make local inhabitants at risk and can also affect agriculture and fisheries • Hospital refuse contain harmful bacteria and viruses that can spread infection
- 35. Disposal methods This dependson the types of refuse and can be one of the following ways: • Crude damping • Burning • Burying • Incineration • Controlled tipping
- 36. Crude dumping • Opendumping or uncontrolled dumping. This is a very unsatisfactory method of dumping because of fly, mosquito and rodent breeding, water pollution, air pollution from smells.
- 37. Proper disposal methods Dryrefuse disposal in urban: • Should be put in a dust bins with heavy well fitting lids to discourage dogs, rats and flies • The dust bin should stand on a firm concrete base be kept clean, scrubbed out regularly and dried in the sun Dry refuse disposal in rural areas: • The rubbish should be burned or buried in a pit • The ashes can be used as manure • Vegetable and fruit peelings can be used as compost
- 38. Proper disposal methodscontd • Animal carcasses should be removed and buried to prevent flies. Veterinary officers should be informed. • Dog excreta should be removed around the home and buried to avoid flies and prevent children from playing on it.
- 39. Incineration/burning • Burning ina simple mud brick incinerator. • A bin incinerator made out of a drum with fire bars across it and air holes underneath is an effective and affordable way of disposal. • Ideal incinerators may be used
- 40. Composting • Wet anddry refuse is heaped onto alternate layers onto a plot about 1.5 metres then covered with grass or earth. • Fermentation decomposes the refuse, which should be turned after 30 days and again at 60 days. • After 90 days, the refuse is ripe and may be put on the land as fertiliser.
- 41. Controlled tipping (controlled burial) •Solid waste is disposed off into a dug pit and regularly covered with soil in form of alternate layers of waste and soil to avoid attracting disease vectors such as flies and rodents
- 42. Health care wastemanagement • Health care waste – waste generated in health care centres • 75-95% of the health care waste is general waste (similar to domestic waste) • 10-25% is hazardous waste (infectious, toxic e.tc)
- 43. Health care waste Note: Healthcare waste should be handled with great care and should be disposed in separate bins for: non-contaminated waste – which include papers from the nursing station, plastic juice bottles contaminated waste - that is infectious sharps - which include contaminated needles and scalpel blades.
- 44. Health care wastecontd Health care activities(human) that generate waste include: • Diagnosis • Treatment • Prevention of disease • Alleviation of disablement • Associated research
- 45. Health care wastecontd Major sources of health care waste: • Hospitals • Clinics • Laboratories • Research centres • Blood banks • Nursing homes • Mortuaries
- 46. Health care wastecontd Hazardous properties of health care waste: • Infectious • Sharps • Pharmaceutical • Genotoxic • Chemical • Radioactive
- 47. Health care wastecontd Hazardous properties of chemical waste: • Toxic • Corrosive • Flammable • Reactive • Explosive • Genotoxic
- 48. Health care wastecontd Who is at risk? • Doctors and nurses • Patients • Hospital support staff • Waste collection and disposal staff
- 49. Health care wastecontd Public health risks (potential health effects): • AIDS • Hepatitis B and C • Respiratory infections • Skin infections • Effects of radioactive substances – cancers, birth defects for unborn babies
- 50. Health care wastecontd Good waste management depends on: • A dedicated waste management team • Good administration • Careful planning • Available legislation • Adequate financing • Full participation by trained staff
- 51. Health care wastecontd Waste management team: • Hospital manager • Waste management officer • Heads of department • Infection control officer • Senior Nursing sister • Hospital engineer • Finance officer • Chief pharmacist • Radiation officer
- 52. Health care wastemanagement Minimization, reuse, recycling and segregation of health care waste: • Waste minimization - reducing the amount of waste produced in a society at the point of production e.g. Plastic water bottles • Reuse: products are used again for the same purpose. Only materials designed to be re- used e.g. Endoscopy tubes i.e. Catheters and plastic syringes should not be reused
- 53. Health care wastemanagement • Recycling – converting waste material into new. packaging material can be recycled e.g. Cardboard boxes, glass, metal container, plastic wrappings . • Waste segregation – dividing waste into dry and wet
- 54. Health care wastecontd • Recommended colour coding of waste plastic bags: • Yellow/ Red for infectious waste • Brown for chemicals and pharmaceutical waste • Black for general use
- 55. Health care wastemanagement Waste collection: • Establish a routine programme for collection e.g. collect ward waste daily • Sharps containers should be sealed when ¾ full and replaced by another one.
- 56. Health care wastemanagement Waste storage facilities: • Impermeable hard standing • Easy to clean • Readily accessible to staff • Secure and lockable • Good lighting and ventilation • Proofed against rodents, insects and birds
- 57. Health care wastecontd Waste storage periods: 48 hours in cool season 24 hour in hot season Waste labelling: Date of production Place Waste quantity Waste quality Waste destination
- 58. Health care wastecontd Final disposal: Municipal landfill Burying inside premises Incineration: • High temperature oxidation process • Reduces to ashes - reducing waste volume & wt • Not all waste can be incinerated e.g. pressurised gas containers, reactive chemical waste
- 59. PEST / VECTORCONTROL
- 60. Outline • What isa vector? • Examples of vectors and their diseases • Vector control steps • General control measures • Mosquito control • Fly control activities • Rodent control activities
- 61. What is avector? • A vector is an organism/agent (Insect/ animal/vermin) that carry disease causing organisms from one animal/person or act as the intermediate host • The vectors do not suffer from the diseases
- 62. Pests/vectors • Vectors/pests spreadsome of the common diseases. • It is useful to consider what can be done to control pests. • The control of insect pests ad vermin should take into consideration the life cycle and the general conditions favourable to their growth. • This enables health personnel to identify possible methods for intervention and control.
- 63. Examples of vectorsand their diseases • Mosquitos: Malaria, yellow fever, dengue fever, elephantiasis • Black flies: Oncorcerciasis (River blindness) • Snails: Schistosomiasis/ Bilhazia • Rodents( rats): plague • Fleas: Plague
- 64. Other common pests •House flies • Bed bugs • Ticks • Tsetse flies • Mites • Human lice
- 65. Vector control steps •Complaint investigation • Identification of routine breeding sites • Surveillance of new or potential breeding sites • Application of appropriate treatment
- 66. Control Measures • Biological:Use of predators • Chemical: e.g. Spraying, baiting (poisoning) use of repellents • Physical: trapping • Use of personal protective equipment • Environmental management – Destruction of breeding sites – Proper environmental hygiene – Proper management of water schemes – Proper disposal of wastes
- 67. Mosquito control • Drainingof water troughs • Repairing of water leaks • Vegetation removal – loan mowing • Proper disposal of empty tins • Removal of floating debris in ponds
- 68. Fly control activities •Trash can rinsing • Keeping lids on trash cans • Bag and tie debris • Burning of refuse • Daily picking of pet and poultry droppings • Reporting about all fly breeding sites
- 69. Rodent control activities •Eliminate openings for rodents in the home • Trap and bait placing along runaways • Best rodent control measures include - Good sanitation - Rodent proof construction - Cats
- 70. General methods tocontrol pests/ vectors • Disposing of all refuse, any decaying matter, faeces properly- that is burying, burning or composting for fertiliser. • Keeping all surroundings clean all the time • Keeping all food vessels and utensils clean • Draining or filling up water holes and ditches. • Clearing bush and grass along the banks of rivers and ponds. • Spraying insecticides in the environment.
- 71.
- 72. Activity • Describe thetypes of environment and their influence on health • Describe environmental degradation and its influence on health • Identify the types of chemicals that may predispose to cancer