[Medical waste incinerator constructed with locally produced materials: experience during the immunization campaign 2002 against measles in Douala, Cameroon]. / Incinérateur de déchets médicaux à base de matériaux locaux: expérience de la campagne 2002 de vaccination anti-rougeole à Douala, Cameroun.

UNLABELLED: Incineration is still the method of choice for disposal of biomedical waste. Combustion at 800+ degrees C eliminates all risk of injury by reducing the waste to ashes and destroying all microorganisms. The purpose of his report is to present a modular double-chambered incinerator in conformity with recommendations for developing countries. The incinerator described here provides the following advantages: suitability for low-cost artisanal construction, excess-air combustion, low risk of accidents and contamination, after-burner for smoke, energy efficiency, easy operation/maintenance, and safety. It is made from locally produced clay bricks reinforced with a steel frame and features two chambers for combustion and post-combustion. It functions on a batch basis with a 2-hour cycle. The immunization campaign against measles that was carried out in 5 districts of Douala in December 2002 produced 800,000 self-disabling syringes with needles. These by-products were immediately discarded in cardboard safety boxes (5-liter capacity, 1 kg) that were taken to the incinerator and burned at the rate of two batches per day. RESULTS: The construction cost of the incinerator was 3,500,000 FCFA (5,300 euros). A total of 5,816 boxes were incinerated, i.e., 29,080 litres, 872,400 syringes, 6,281 kg. Incineration required 126 batches over a period of 11 weeks. The ashes (240 litres, i.e. 0.8% of the total incinerated volume) were virtually free from solid residue. Fuel consumption was negligible. Smoke was never excessive, thick or odorous. Temperatures measured during preliminary trials were always above 800 degrees C. According to the WHO, toxic emissions are negligible if incineration is carried out at temperatures higher than 700 degrees C for less than 2 hours a day. Further study will be necessary to confirm this preliminary experience with regard to temperature control and smoke/ash composition and to test the incinerator in various climatic and operating conditions.

Incinerateur de dechets medicaux a base de materiaux locaux : experience de la campagne 2002 de vaccination anti-rougeole a Douala; Cameroun

Methode de choix pour detruire les dechets biomedicaux; l'incineration consiste a les reduire en cendres par une combustion a 800oC; detruisant les micro-organismes;supprimant les risques de blessure. L'incinerateur presente; de type modulaire double chambre preconise en pays en developpement; repond aux principes de : fabrication artisanale peu couteuse; combustion en exces d'air; reduction des risques d'accident ou de contamination; postcombustion des fumees; economie d'energie; manipulation et entretien faciles; securite d'utilisation. L'incinerateur; en briques d'argile de fabrication locale; solidarise par des cornieres d'acier; comporte deux chambres pour la combustion et la post-combustion. Un reservoir de carburant et un ventilateur permettent d'activer la combustion. Lemodele fonctionne par fournees en cycles de 2 heures. La campagne de vaccination anti-rougeole (decembre 2002) devait produire pour 5 districts deDouala 800000 seringues autobloquantes avec aiguilles. Immediatement jetes dans des boites de securite de carton (contenance 5 litres; 1 Kg); ces dechets etaient achemines jusqu'a l'incinerateur puis incineres en 2 fournees quotidiennes. Resultats. La construction de l'incinerateur a coute 3500000FCFA (5300 _). 5816 boites ont ete incinerees; soit 29080 litres; 872 400 seringues; 6 281 Kg de dechets. Leur incineration a necessite 126 fournees realisees en 11 semaines. Les cendres (240 litres; soit 0;8du volume incinere) ne contenaient pratiquement aucun residu solide. La consommation de gazole a ete negligeable. Les fumees n'ont jamais ete abondantes; opaques; ou malodorantes. Les temperatures mesurees lors d'essais prealables depassaient toujours 800oC. Selon l'OMS; les emissions toxiques sont negligeables au-dela de 700oC si l'incinerateur fonctionnemoins de 2 heures quotidiennes. L'experience devra etre completee par des travaux sur le controle des temperatures; la determination de la composition des cendres et fumees; des essais en differentes conditions climatiques et d'utilisation