No. 13 Improving Indoor Air in Rural Bangladesh: Results of Controlled Experiments by Susmita Dasgupta, Mainul Huq, M. Khaliquzzaman, and David Wheeler In rura l Ba ng la d e sh, Ind o o r A ir Po llutio n (IA P) is dang e ro usly hig h fo r p o o r ho use ho lds de p e nde nt o n b io m ass c o o king fue ls. Base d o n e arlie r Wo rld Bank re se arc h, c o ntro lle d, sc ie nti fi c ally m o nito re d e xp e rim e nts we re c o nduc te d in Burum di v illag e , Naray ang anj Distric t, to te st the e ffe c ts o f struc tural a rra ng e m e nts a nd v e ntila tio n p ra c tic e s o n IA P. Find ing s sug g e st o p tim a l struc tura l c ho ic e s a nd villag e - le ve l m e asure s to re duc e IAP e xpo sure . Most of Bangladesh’s rural households collect or pur- chase biomass—fuelwood, cow dung, crop residues, tree leaves, and grass—to cook all or part of their meals, using traditional, fixed clay stoves. The high moisture content of biomass cooking fuels, combined with the inefficiency of traditional stoves, results in incomplete combustion, producing indoor air pol- lution (IAP) (Asaduzzaman, Barnes, and Khandker 2009). 1 Recent World Bank research using the latest air-monitoring technology and results of a national household survey show that, for respirable airborne particulates (PM 10 ), 2 concentrations of 300 μg per m 3 or greater are common, implying widespread exposure to a serious health hazard (Dasgupta et al. 2006). 3 Stud y Ra tio na le To date, most IAP studies have focused on the use of modern fuels, such as kerosene and liquefied pe- troleum gas (LPG), and improved stove designs. But structural arrangements—from building materials and space configurations to cooking locations—and ventilation practices are also a major issue. Testing the significance of these factors in reducing IAP exposure is particularly important in rural Bangladesh, where many poor families are likely to depend on biomass cooking fuels and stoves for some time. 4 Stud y Me tho d Architects familiar with the climatic conditions and cul- tural constraints faced by poor Bangladeshi households studied building materials, housing configurations, and construction techniques in various regions of the country to develop a set of structural options. At each site, local workers were hired to construct experimental houses identical to the structures used by poor families in the area, using standard local building practices. Four sets of houses were built, corresponding to per- manent walls made of thatch, mud, corrugated iron (tin), and brick. The thatch-, mud-, and tin-walled houses had mud flooring on rammed earth; while the brick-walled houses had conventional cement concrete flooring. Roofing materials were altered to produce a variety of standard combinations (Table 1). The axes of the houses were aligned in a north-south direction to capture varying wind conditions. Houses were furnished to simulate life settings. Within these diverse sets of cooking environments, housewives cooked the standard midday meal for a family of four on traditional stoves. 5 Four common space configurations for kitchens were used: interior, attached, detached, 6 and open air. For attached and detached kitchens, construction materials for walls, floors, and roofs varied. 7 Kitchen configurations and 1 Ac c o rd ing to the Wo rld He a lth O rg a niza tio n, a c ute re sp ira to ry infe c tio n fro m IAP kills a n e stima te d 1 millio n c hild re n p e r ye a r in d e ve lo p ing c o untrie s (se e WHO G lo b a l a nd Re g io na l Burd e n o f Dise a se Re p o rt, 2004 [www.who .int/ p ub lic a tio ns/ c ra / e n]). 2 PM10 re fe rs to p a rtic ula te ma tte r with a d ia me te r o f 10 mic ro ns. 3 In e ig ht Ita lia n c itie s with fa rlo we ra nnua lc o nc e ntra tio ns (45–55 μg pe r m 3 ), G a la ssi e t a l. (2000) fo und tha t re d uc ing PM10 c o nc e ntra - tio ns ha d sub sta ntia l he a lth b e ne fi ts. Tra d itio na l sto ve use in Burumd i villa g e . ESMAP Knowledge Exchange Series No. 13 1 KNOWLEDGE EXCHANGE SERIES March 2009 4 Burumd i villa g e , lo c a te d 27 km so uthe a st o f the c a p ita l c ity o f Dha ka , wa s se le c te d a s the stud y site . Mo st o f Burumd i’ s 1,600 re si- d e nts (a b o ut 290 ho use ho ld s) a re e ithe r se lf-e mp lo ye d wo rke rs in no na g ric ultura l se c to rs o r se rvic e p ro vid e rs. The ne a re st se c o nd - a ry ro a d a nd ma nufa c turing ind ustria l unit a re e a c h lo c a te d 3 km fro m the villa g e ; o the r p o te ntia lly p o lluting ma nufa c turing ind us- trie s a re mo re tha n 10 km a wa y. No villa g e rs o wn mo to r ve hic le s fo r p riva te tra nsp o rt o r mo to rize d a g ric ultura l e q uip me nt. 5 The mid d a y me a l c o nsists o f ric e , le ntils, ve g e ta b le c urry, a nd fi sh. 6 A sp a c e e nc lo se d b y wa lls a nd a ro o f lo c a te d a sho rt d ista nc e fro m the ho use . 7 Va ria tio ns we re tha tc h, mud , tin, a nd b ric k (wa lls); c e me nt, c o n- c re te , a nd mud (fl o o rs); a nd tha tc h, tin, a nd c o nc re te (ro o fs). 48647 Public Disclosure Authorized Public Disclosure Authorized Public Disclosure Authorized Public Disclosure Authorized