Households used a variety of cooking fuels (Table 5). A different fuel
was often used at the start of cooking or to light the fire. For example,
straw and kerosene were commonly used at the start of cooking,
but not as the main cooking fuel. About one-third of households used
wood, one-third animal dung, and one-third gas, as their main fuels.
It was common for families to alternate between fuels, usually with
wood and dung. Animal dung cakes normally contained a small amount
of wood or plant products to give them structure. The use of gas as a
main fuel was more common in urban than rural settings (60.8% compared
with 15.8%). The opposite was true for wood (27.2% compared
with 41.7%) and dung (9.4% and 36.2%). Stoves were usually simple
open fire designs of mud and clay with no chimney or hood. Cooking
was done mainly indoors in the kitchen, and 786 (94%) households
cooked indoors every day of the year.
Table 3
Weighted average respirable particle mass over the year, calculated by applying a weighting to each sample of 1 / (n × 3), where n= number of samples in that location in a season.
Location Number of samples Standardized mean (μg/m3) 95% Confidence interval
Bedroom Urban cement roof 30 116 87.8 to 144
Urban tiled roof 12 233 133 to 333
Urban straw roof 4 134 109 to 159
Rural cement roof 19 175 134 to 217
Rural tiled roof 22 125 50.6 to 199
Rural straw roof 9 236 120 to 351
Combined roof urban 47 166 117 to 215
Combined roof rural 50 192 135 to 249
Veranda Urban 15 592 281 to 902
Rural 16 445 264 to 627
School Urban 14 121 82.4 to 160
Rural 8 123 37.5 to 209
Outdoors Urban 19 131 80.7 to 181
Rural 19 202 128 to 276
Kitchen cooking Biomass together 21 908 614 to 1203
Non-biomass 10 175 63.2 to 286
Kitchen no cooking Biomass 21 438 −138 to 1010
Non-biomass 8 213 −15.8 to 442
Fig.