2,432 bytes added,
15:32, 4 August 2007 [[Image:Ceramic_filter_icon.png|right]]
A new alternative to conventional ceramic candle filters is the CSP filter. This model has a pot-shaped ceramic filtering element that is treated with colloidal silver. It has a bigger capacity and is easier to produce locally than candle filters. Also leakages are easier to detect than in candle filters so there is less risk in use.
Evaluations, including a USAID-funded test in Nicaragua, indicate that CSP filters remove turbidity and harmful bacteria that cause diarrhoea, cholera and other waterborne diseases. Maintenance consists of cleaning with a brush and changing the ceramic element every 2-3 years. If filled twice a day the filter produces enough for a family of six.
Field studies have shown that investment in a filter is "paid back" within 3 to 6 months because of savings on expenses for medicines, fuel wood and labour. In Nicaragua, Guatemala and Cambodia the production of this filter is a commercial activity and production is starting up in six other countries.
[[Image:Ceramic_filter.PNG|thumb|right|150px|Family using a CSP filter in Zapatera, Nicaragua.]]
{| border="1" cellpadding="5" cellspacing="0" align="center"
|-
! width="50%" style="background:#efefef;" | Advantages
! style="background:#ffdead;" | Disadvantages
|-
| valign="top" | Bigger capacity and safer than candle filters.<br>
| valign="top" |<br>
|}
== Capacity ==
10-20 litres/day.
== Costs ==
Complete filter (off-factory): US$ 8 in Cambodia US$ 10-15 in Nicaragua.
== Applying conditions ==
<ul>
<li><b>Numbers:</b> 150,000 in Central America, Asia and Africa.</li>
<li><b>Applied by:</b> CARE, UNICEF, Red Cross and others.</li>
<li><b>Cost of introduction:</b> US$ 15,000 - 30,000 for project incl. training, machinery and a first production of 500 filters. US$ 50,000 - 100,000 for project incl. production shop, training, first promotion, and 5,000 filters</li>
</ul>
== Rope pump building manual ==
PRACTICA foundation and the Technical Training Programme of the ETC Foundation (TTP/ETC) have put together a really [http://www.greenocean.org/akvo/PRACTICA_180306_Rope_pump_manual_Ethiopia_March_2006_complete.pdf excellent manual on how to build rope pumps] (PDF, 2.5 Mbyte). It is an 86 page long document with detailed instructions.
== External links ==
[http://www.who.org www.who.org ]
[http://www.potpaz.org www.potpaz.org ]
[http://www.elfiltron.com www.elfiltron.com]