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The economic benefits of the project
would vary depending on the solution.
Training would be provided by Vigyan
Ashram.
It should be kept in mind that trash
other than plastic packaging is already
being used in the community. Metals
and plastics are sold as scrap and
food waste is eaten by pigs that are
owned by community members. When less
food waste is available, pigs sometimes
begin eating crops of local farmers,
which is very undesirable. Waste management
solutions should be wary of upsetting
either of these conditions.
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| Vigyan Ashram will
use the water testing kit as a practical
teaching aid and also to test local
water supplies when contamination is
suspected. Vigyan Ashram also offers
well site locating facilities, so once
the well has been located and dug it
could be tested to ascertain its level
of purity and the level of treatment
that is required.
Two potential projects have been
identified:
1) To develop or modify an existing
water testing system. The new system
should, as much as possible, use the
apparatus already available at Vigyan
Ashram.
2) To design an incubator that does
not rely on electricity and can be
manufactured by Vigyan Ashram. The
local community should eventually
learn how to make and use the incubator,
thereby becoming self-reliant and
having the capacity to design water
testing systems themselves in the
future.
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It has been estimated
that the inhabitants of Pabal spend
40-50% of their income on medicines
and doctor's fees. Diarrhoea and gastrointestinal
infections are the most common forms
of illness treated by doctors in Pabal.
A water testing kit will allow people
to more easily avoid drinking contaminated
water, leading to fewer cases of water-borne
illness and hence a reduction in medical
costs for the population.
When deciding how to implement the proposed
design solution students should take
into account the substantial cost to
the environment of flying to India.
The implementation of improved water
testing facilities will potentially
reduce the income of doctors and pharmacists
in Pabal and will also encourage a
reliance on technology, where there
is no urgent need. However since the
solution is designed for Vigyan Ashram,
an educational establishment, they
are well placed to deal with these
issues.
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Many people currently treat water
indiscriminately by boiling, filtration
or chlorination. Others only treat
their water after they have become
ill. Drinking potentially polluted
water is expensive in terms of medical
bills and discomfort and indiscriminate
treatment of water is not good for
the environment and reduces people's
natural immunity. Therefore, routinely
testing water supplies seems a suitable
way of reducing the chance of illness
in a more sustainable way than the
current practice.
Although electricity is relatively
cheap and readily available, there
are regular power cuts. Solutions
should take this into account.
Although some people have car batteries
for lighting during power cuts, this
is a luxury enjoyed by the wealthier
villagers. Vigyan Ashram uses batteries
for lighting and to ensure that staff
have access to email. People are unlikely
to happily use anything reliant on
batteries, as the following example
illustrates: Vigyan Ashram was given
a solar cell and battery to run an
additional tube light during power
cuts, but found that the batteries
in the system only last for one year.
So, while the system saves Vigyan
Ashram Rs. 400 on electricity, it
costs Rs. 800 to replace the battery,
and so the solar cell is no longer
used.
Fuel is relatively expensive and
so is often used only when absolutely
necessary or where it provides a valued
luxury such as hot water for washing.
Refer to the engINdia Final Report
for further details.
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| A possible solution
could be a design based on the Del Agua
water testing kit used by Oxfam. This
kit could be usefully modified in three
areas to make it more suitable for use
in Pabal: 1) The Del Agua kit is currently
battery powered, making it expensive,
heavy and reliant on routine access
to a stable power supply. 2) Although
the kit has the potential to give an
accurate reading for the concentration
of faecal coli forms, in practice the
result given is normally, "none,"
"a few" or "too many
to count." The process could therefore
either be simplified to reflect the
level of accuracy attained in the field,
or a system could be devised to enable
the operator to give an accurate reading
for the concentration of faecal coli
forms. 3) The kit is reliant on a factory-produced
rather than a locally-produced membrane.
(This membrane collects faecal coli
forms and then acts as a surface for
incubation of those coli forms into
colonies that are large enough to be
visible to the naked eye.)
Many people use a form of ceramic
filter technology that is produced
locally by the kumber (potter). Essentially
it is a pot made from a mixture of
clay and charcoal placed on a stand
above a collecting basin. The pot
is filled with water, which is presumably
filtered as it percolates through
the pot and then drips into the collecting
basin. A similar system based on compressed
rice husks has also been developed
in a nearby village. Both systems
have the potential to provide a replacement
for the membrane necessary in a Del
Agua-style water testing kit.
When designing a method of incubation
it should be noted that the ambient
temperature in Pabal is higher than
in the UK (see the engINdia Final
Report). This may mean that an alternative
heat source (such as the heat of the
sun) is more viable than it would
be in the UK.
The testing procedures carried out
by Vigyan Ashram are not as accurately
performed as we would expect in the
UK or US. This possibly reflects the
scarcity of resources, the fact that
accuracy does not seem to be so heavily
valued as in the US and UK or the
rural location and level of training
at Vigyan Ashram.
Vigyan Ashram has:
Electric water bath (set at approximately
40°C)
Thermometer (-10 - 360°F)
Mechanical balance (1mg - 100g)
Masses (200mg x 6, 500mg x 3, and
one each of: 1g, 2g, 5g, 10g, 20g,
50g, 100g)
Burettes (1ml 1/100, 2ml 1/50)
Pipettes (5ml, 10ml)
Plastic dropper
Pressure cooker (capacity approx.
7 l)
Paraffin stove
Test tubes (x5)
Thurum tubes (very, very small test
tubes, x5)
Plastic beaker (200ml x 1)
The water test currently used by
Vigyan Ashram is as follows:
o Weigh 1.2g of Mac Conkey Broth powder
and dissolve it in 30ml of distilled
water.
o Boil this for 2 minutes to expel
any O2 from the solution.
o Allow this to cool, then pipette
5ml of solution into each of 5 test
tubes.
o Use a dropper to fill a thurum tube
(very, very small test tube) with
solution from the test tube and then
drop an inverted thurum tube into
each of the test tubes. (N.B There
must not be an air bubble in the thurum
tube that sits inverted at the bottom
of each test tube.)
o Fill the end of each test tube with
cotton wool and place all 5 test tubes
into a plastic beaker.
o Prepare a pressure cooker with an
inch of water at the bottom, half
fill the beaker with water and place
the beaker into the pressure cooker.
o Heat the pressure cooker on the
paraffin stove. Once the pressure
valve has risen and fallen 3 times,
turn off the stove and allow the pressure
cooker to cool. (This sterilizes the
solution and test tubes.)
o Once the pressure cooker can be
opened remove the beaker, pour out
the water and allow the test tubes
to cool for 5 minutes.
o Then pipette 5ml of potentially
polluted water into each test tube
and place the test tubes in the pre-warmed
water bath (set at approximately 40°C,
a thermometer was not used to confirm
this) for 48 hours. (This pipette
was not sterilized before or after
use.)
o If three or more of the five test
tubes show a colour change from pink
to yellow then the water is not safe
to drink (this shows that pathogens
are present since the nutrient has
been digested).
o If three or more of the five test
tubes have a floating thurum tube
then the water is not safe to drink
(this shows that pathogens are present
since CO2 has been produced).
o In other cases the water is considered
safe to drink.
Vigyan Ashram was asked to test some
rain water that had been collected.
This water appeared to be unsafe to
drink from the level of floating organic
material and its smell. However it
was passed as safe by the above test
and so was drunk by a so to confirm
this result a member of the team drunk
only this water for four days with
no ill effects showing that this test
is probably useful in spite of its
limitations.
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