Bs. Nursing CHN Lacture

1. By : Aasan DasBy : Aasan Das
Student: ICoNM- DUHSStudent: ICoNM- DUHS

2. Objectives
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By the end of the presentation students will be able to:
Define solid waste and sewage
Discuss methods of solid waste disposal and
sewage disposal
List fecal-borne diseases and it’s control
Share role of a community health nurse in
community for waste management
Discuss rodents, their role in disease transmission
and their control

3. Facts about garbage
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
Changing lifestyles, the increasing use of
disposable materials (plastic bags instead of
taking container for milk).
Excessive packaging contributing in
increasing waste.

4. 
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
Waste management is now a global concern
as quantity and diversity of the nature of
waste has changed.
Financial limitations in large cities for
disposing garbage.
The problem is not only confined to land, it
includes air and water as well.
Cont...

5. Causes of improper waste
disposal
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Waste pollute land, air and water ( cause
environmental pollution).
It gives pests and insects (mosquitoes,
house flies, cockroaches, ants, and rats)
platform to breed.
It causes intolerable nuisance of sight
and smell.

6. 

It causes infections, diseases and
allergies.
It effects physical, mental and social
health.
Cont...

7. Sources of waste
1.
2.
3.
Three sources:
Household waste (municipal waste)
Industrial waste (hazardous waste)
Biomedical waste or hospital waste
(infectious waste)

8. Types of waste
Refuse/
Solid waste
Excreta/
Sewage
Sullage

9. Refuse/Solid Waste
–
–
–
Waste material coming from houses, streets,
commercial, industrial and agricultural
activities of man is called refuse it is further
classified as:
Garbage (waste from food stuff)
Rubbish (Dirt, dust, paper, clothing, glass,
rubber, wood and plastic material)
Ash (residual of fuel)

10. Sullage
Type of waste containing all liquid wastes,
water or slop water including industrial
waste but excludes night soil is called
sullage.

11. Excreta/Sewage
•
•
Implies to feaces.
Sullage containing night soil (feaces)
is called sewage.

12. Stages of solid waste
removal
1.
2.
3.
4.
5.
Segregation
Storage
Collection
Transportation to disposal point
Disposal

13. Waste Segregation
Bio-degradable
(kitchen waste,
vegetables, fruits,
leaves from garden
and paper)
Non
Bio-degradable
(recyclable waste,
toxic waste, soiled waste
•
•
•
Recyclable waste: plastic, paper, glass, metal
Toxic waste: old medicine, paints, chemical,
fertilizers, pesticide, containers, spray can
Soiled waste: hospital waste, cloths soiled with
blood, body fluids.

14. Collection methods
1. Hauled Container System
Containers loaded with municipal sewage waste
are taken to the disposal site, emptied and
brought back to the same site or to the next site.
In Pakistan, the container is mostly transported
from one place to another with the help of a
truck or tractor.

15. 2. Stationary Container System
In this system, the containers are
emptied into vehicles, so a number of
containers can be emptied in one trip.
Cont...

16. Recycling and Reuse
•
•
•
•
Items that can be reused or recycled:
Paper: old copies, old books, paper bags,
newspapers
Plastic: containers, bottles, bags, sheets
Glass: bottles, plates, cups, bowls
Miscellaneous: old cans, utensils,
clothes, furniture

17. Advantages of recycling
•
•
Waste recycling has some significant
advantages.
It leads to less utilization of raw materials.
It reduces environmental impacts arising
from waste treatment and disposal.

18. •
•
•
•
It saves money.
It reduces the amount of energy required to
manufacture new products.
It saves landfill space.
It makes the surroundings cleaner and
healthier.
Cont...

19. Methods of refuse disposal
Dumping
Composting
Sanitary
Filling/land fill
Incineration

20. Dumping
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Refused is dumped on vacant land.
It should be done away from residential
area.
The waste is untreated, uncovered, and
not segregated.
It is the breeding ground for flies, rats
and other insects that spread disease.

21. 

The rainwater run-off from these
dumps contaminates nearby land and
water thereby spreading disease.
In 1967 WHO declared that it is
unhealthy and it should be stopped.
Cont...

22. Land fill/ tipping
• Unlike open dump, a pit is dug in the
ground. The garbage is dumped and
pit is covered. Thus preventing the
flies and rats.

23. • At the end of each day layer of soil
is scattered on top and equipment is
used to compress garbage. Once
the area is filled then it is covered
with thick layer of mud. and later
site is developed as parking area or
park.
Cont...

24. Problems with Land fill
• All types of waste is dumped and
when water sweeps over them it gets
contaminated and also this pollutes
through surrounding and may cause
leaching.

25. Sanitary landfills/ Controlled tipping
•
•
•
Refuse is placed in designated area in
such a manner that it will solve leaching
problem to some extent.
Area is dug to 6 feet deep in ground.
Like land fill, refuse spread out and
compacted. At the end of each day this

26. •
•
•
layer is covered with earth and compacted
manually or tracker or bulldozer can be
used.
After 4-6 months dug is open and manure
is removed for agricultural used.
This method prevents flies and rats.
Cont...

27. Problems of Sanitary land fills
•
•
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Not all material degrade
Expensive
It also contaminate ground water so
should not be near water sources
Methane gas is produced if little
oxygen goes inside.

28. • (As land fill utilizes anaerobic process
for decomposition ). Methane is
combustible, in air is explosive, non
toxic when inhaled, but it can produce
suffocation by reducing the
concentration of oxygen inhaled.
Cont...

29. • In some countries through this method
methane is being produced and sold as
CNG. (CNG is compressed methane used
in some countries for vehicles).
Cont...

30. Composting
•
•
Refuse along with the excreta is disposed
off.
Process:
Pits or trenches are dug 3 ft deep
Alternate layers of refuse and night soil are
spread in trenches in proportion of 6 inch
thickness of refuse and 2 inch

31. •
•
thickness of night soil.
The pits are then covered with earth and
compacted.
Due to bacterial action, intense heat is
generated within the compost pits, which kills
all the pathogen and other organisms.
Cont...

32. •
•
•
Pit gradually cools down.
After 4-6 months the decomposing is
complete. The result produced is manure /
fertilizer, which is used for agriculture.
This method is called a hot fermentation
process.
Cont...

33. Incineration/burning
It is used where refuse can not be carried
away over long distance. It is best used for
hospital/infectious refuse disposal.
(syringes, needles and drips). Incinerator
should be properly planned and designated
that it does not cause harm to the
environment. Ash generated from this
process can be toxic, if discarded inland fill
can enter in ground water and may
contaminate it

34. Excreta / Sewage
•
•
•
•
Human excreta has major pathogens
Higher the contact with excreta higher the
risk of contacting disease.
Streptococci, E-coli, Salmonella ( and
others discussed in water borne diseases
mainly result from fecal contamination)
Recreational water and beaches may be
contaminated with sewage.

35. Methods of excreta disposal
Non Sewerage
a. Dry/
Conservancy
method
b. Sanitary
Latrines
Sewerage
Wet/ Water Carriage /
Sewage method
a. Conservancy/ dry method:
This method involves manual collection and
removal of human excreta to the disposal
point. There are three methods used for
disposal of this material.

36. •
•
•
•
•
•
Incineration
Compositing
Trenching
Trenching: The excreta are moved to a place at least one
mile from town. The
trenching ground-which has narrow trenches, must be
of porous layer. The
excreta is pored into the trenches and covered with
soil. After one year, the
excreta are decomposed and safe for the use as a
crop fertilizer.

37. Disadvantages of dry system
•
•
•
•
•
Recruiting sweepers and lorries
Odor
Flies
Danger of pollution and infection
Large area is required

38. •
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b. Sanitary Latrines:
The place used for defecation or urination
is called ‘latrine’ or ‘privy’. The qualities of
a good latrine are:
Simple in construction and in use. For
example, it should have a roof, a cemented
platform, and a seat.
Locally available, and should not involve
manual handling of excreta.

39. •
•
•
It should be hygienic and sanitary, and
should not lead to environmental pollution.
For example: (excreta should not pollute
the ground or surface water and the soil.
Feaces should not be exposed to flies,
rodents, and animals.
Excreta should not create the irritation due
to smell or its appearance.
Cont...

40. •
•
•
•
•
•
A global field survey project under taken by the
World Bank in 39 countries around the world
identified the following types of sanitary latrines.
Pit hole latrine
Bore hole latrine
Aqua Privy
Bucket latrine
Over hung privy
Flush latrines
Types of latrines

41. Pit hole latrine:
It is the simplest form of rural latrine. Consists
of a hand dug hole in the ground covered
with either a squatting or plate. The super
structure that gives privacy and protection
from the elements can be made of any
material
but should be strong enough to with stand the
weather. It is simple in design and can be
used for 5 years for 6 family members.
Cont...

42. • It doesn’t require handling of fresh feces.
It can be built during short periods like
camps.
(2m deep/1m diameter)
Cont...

43. Bore hole latrine:
Is a type of pit privy is dug with a special
machine (hand earth augar). A bore is 16
inches in diameter and 18 feet deep from
supra structure. Because of the depth of
the hole, the excreta do not attract flies or
liable to
the bacterial action.
Cont...

44. Aqua privy:
It is also called as ‘septic toilet’. The aqua privy
consists of a tank filled with water into which a
drop pipe hanging from the latrine floor. The
excreta and the urine fall through the drop pipe
into the tank where they under go anaerobic
decomposition as in septic tank. The digested
sludge, which reduced to about a quarter of the
volume of the deposited excreta, accumulates
in the tank and has to be removed at intervals.
(Similar in airoplanes)
Cont...

45. Bucket latrine:
In bucket latrine the feaces are passed
into a container in which there is some
soil. There is supply of soil, to sprinkle
over the feces. It is not satisfactory
method as it is a great source of
infection and infestation. If properly
disposed in a pit then can be used as
fertilizer.

46. Over hung privy:
May be found in areas where there is plenty
of water (sea, river, lake) .However, it is not
considered to be a satisfactory method.
Here there is no container, but the waste is
dropped directly in the water, so that the
feaces and the urine falls into it and gets
disposed of by the action of tide or water
flow.

47. Flush latrines:
•
•
•
It is found in many urban areas. They are
expensive.
Urine and feces are passed into the pan
and it is cleaned by flushing water from a
tank into the pan.
This pan is connected to the sewage
disposal system and to prevent the odors
and germs coming back into the pan from
the sewage

48. Summarization

49. Water carriage system/ Wet method/
sewerage system:
Sewerage system involves carriage of
sewage, (liquid wastes and human
excreta) through a system of drains and
sewers from the point of origin (houses,
institutions, and factories) to the point of
disposal with the help of water.
(for example sewerage treatment Plan)

50. 

Elements of sewage treatments
Water closet: Here human waste is
collected and by flush system removed
to the house drain.
Soil pipe: It is through the pipe that the
sewage is carried from water closet till
the house drain.

51. 

House drain: It is the pipe that runs from
soil pipe to the sewer. it is underground
and receives also waste water from bath
and kitchen.
Inspection chamber and trap: Is
underground airtight cement vault
protecting home from getting sewage
again. After passing through the chamber,
a trap disconnects the house drain from
public sewers. It also prevents the entry
of gases into the house drain.

52. 

Sewer: A public pipe which collects the
sewage from the house drain and
becomes the part of city’s sewerage
system.
Disposal plant sewage purification: A
large quantity of sewage from a total
community is offensive in smell and
contains millions of bacteria. It has to be
purified to protect the health of the
community by a to sewage plant for
treatment.

53. •
•
Aims of sewage treatment plant
Separate inorganic form of organic
material.
To dispose of sewage in healthy
manner.

54. • Human excreta is a source of infection. It
contains pathogenic organism (bacteria,
viruses, protozoa, helminthic parasites.
Therefore, it should be disposed off in a
hygienic way. The health hazards include
soil pollution, water pollution, food
contamination, and breeding of flies.
Harmful hazards of
Excreta sewage

55. Disease caused by improper
disposal of waste
• Typhoid, intestinal worms, paratyphoid
fever, diarrhea, cholera, dysentery, viral
hepatitis, poliomyelitis

56. Chain of transmission of fecal borne
diseases
• Ger

57. Prevention
•
•
•
Diseases can be prevented by:
Proper sanitary latrines
Proper hand washing
Sewage treatment

58. Process of sewage treatment
Screening
Removal of grit
Primary sedimentation
tank
Biological treatment
Aeration tank (effluent/ liquid)
Primary
treatment
Secondary
treatment

59. Screening
• Floating solid is removed by a
Iron bars to prevent blocking of
pumps.

60. Removal of grit
• Inorganic solid such as sand and
gravel is taken and after that it is
used for road filling.

61. Primary sedimentation tank
• Sewage flows in this tank for 6-8
hours and other sewage settle down
and form a black mud called sludge.
Sludge is taken in to another tank and
effluent pass on further in septic tank
for purification.

62. Secondary treatment
1.Biological treatment
Sludge carried to digestion tank
where oxidation makes it dry. This last
product is used as fertilizer.
2.Water in sedimentation tank is moved
in aeration tank here chorine is mixed
to remove odor and reduce bacteria
and then send in to river or sea.

63. 1.
2.
3.
4.
Other methods of sewage
disposal are:
Sea out falls (treat before disposing)
River out falls (treat before disposing)
Land treatment
Oxidation ponds ( sunlight and bacteria)

64. 3rd method liquid portion is carried away
by the ground water on dry send and
loamy soil where it is treated as slow
sand filter.
4th –pond is dug, waste is carried there.
Sun light and bacteria feed on organic
matter and produce CO2, algae take up
CO2 and leave o2 in air.

65. Community education for refuse and
sewage disposal
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–
–
Educate people about dangers to health
and diseases spread by following:
Dry refuse left on ground, or
thrown into water
Waste collection near houses and
wells
Defecation on the ground (need to
dig hole and cover it after
defecation)

66. –
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–
–
Fly breeding from excreta to food so
cover food properly
Spread of hook warm (Do not walk bare
footed on soil)
Improve environmental sanitation (clean
streets, get off from refuses and flies).
Ensure proper drainage for sullage water,
and proper use of sanitary latrines
Cont...

67. Reference
• Iliyas, M., & Shah, K. S. (2000). Disposal of
Waste. In Iliyas, M., Malik, G.Q., Ansari,
M.A., Mubasher, M., & Khan, I. A.
(Editors). Community Medicine and Public
Health. (5th ed). pp. 601–631. Karachi:
Time Traders.