Script 38.6

Notes to broadcasters

Note: This double vault dry alkaline fertilizer family (DAFF) latrine was adapted from the successful Vietnamese double vault latrine by the Centro Mesoamericano de Estudios sobre Tecnologia Apropiada (CEMAT) in Guatemala. During 1982 86, CEMAT transferred the DAFF latrine technology to 10 national and international NGOs and five public national institutions working in the field of sanitation. At the international level, the technology was transferred to Mexico, the Dominican Republic, and Panama. At a session in Mexico, 43 community leaders from 7 countries were trained in DAFF latrine technology.

Later, in 1986 87, a survey conducted in Guatemala showed that sixteen institutions had installed 3000 DAFF latrines. CEMAT supported these groups with training programs about how to promote acceptance, sanitary control and maintenance, and strategies to research the fertilizer quality. National workshops have been organized to discuss the benefits and limitations of the latrines and videos and demonstrations have been used to educate farmers.


A new type of latrine improves health by breaking the cycle of fecal contamination and the spread of diseases such as diarrhea, hepatitis, typhoid, and parasitic infections. It also provides farmers with fertilizer for their crops. The high quality organic fertilizer produced by the new latrine reduces farmers’ costs and helps to avoid the long term environmental problem caused by chemical fertilizers.

Other advantages of the latrine are that it requires no digging, is built with local materials, and does not pollute soil or water, which is a hazard of pit latrines. It also produces fewer microorganisms than pit latrines, and so reduces the risk of disease.

The latrine is an above ground, two chamber system. A portable toilet seat is placed over the opening of one chamber. Each chamber funnels off urine into a special container. The urine is mixed with water and allowed to stand for three days at which time it can be used as a liquid fertilizer. After each defecation, wood ash or a mixture of soil and lime is placed in the chamber. This keeps the deposit dry, inhibits odours, reduces the number of flies, and helps speed the composting process so the fertilizer is ready to use more quickly. The toilet seat is moved to the empty chamber when the first chamber is full. The first chamber is then closed off for six months, while heat and evaporation eliminate the moisture, thereby killing the bacteria. The contents are transformed into a safe, rich fertilizer. An opening in the back wall of the chamber gives easy access to the fertilizer.

The latrine can be built with soil, adobe, brick, cement or stone, bamboo or cane, and grass.

The technology is especially useful in areas where it is difficult to dig pit latrines. It is important that the community be involved in planning the latrine project and well trained to use it.

The cost of the latrine depends on the materials used. The entire unit can be built with cement, mud, and grass for less than 100 U.S. dollars.


This article was published with the aid of a grant from the International Development Research Centre (IDRC), Ottawa, Canada. It is adapted from 101 Technologies from the South for the South, 1992, IDRC, P.O. Box 8500, Ottawa, Canada, K1G 3H9.

Information Sources

CEMAT (Mesoamerican Center for the Study of Appropriate Technology) 28 Av. 18 80, Zona 10 Apartado Postal 1160 Guatemala 01010 Guatemala Tel.: (502) 2 394804. Information available in English and Spanish.

Ficha No. 1: La Letrina Abonera Seca Familiar (Dry composting family latrine), CEMAT, 1990, 37 pages. CEMAT, 28 Av. 18 80, Zona 10, Apartado 1160, Gutemala 01010, Guatemala.

Manual in Spanish on the building, maintenance, use, advantages and agronomic use of the DAFF latrine.

“Urban alternatives: the dry box” in Dialogue on diarrhoea, Issue No. 57, June August 1994 (published in English, French, Spanish, Portuguese, Tamil, Vietnamese, Chinese and Bangla). Appropriate Health Resources and Technologies Action Group (AHRTAG), 1 London Bridge Street, London SE1 9SG, U.K.

Manual para la construction de un sanitario abonero (How to build a composting latrine), Juan Ramon Prado Bustamente, 1994, 66 pages (in Spanish). Educacion Cultura y Ecologia, A.C., Apartado Postal 192, 24000, Campeche, Mexico.

“Raised receptacles and double vault composting latrines” in Ageways, March 1987. HelpAge International, St. James’s Walk, London, U.K. EC1R 0BE.