Poor urban environments: use of paraffin and other fuels as sources of indoor air pollution.

(69% of households) and paraYn (64% of households) were the most commonly used fuels.Gas and wood were used in only 10% and 4% of households respectively,and then only in combination with electricity or paraYn. No houses had chimneys and all but two houses reported opening of windows or doors to circulate fresh air during the monitoring period. The mean maximum hourly average was 0.015 ppm (range 0.00‐0.24) for NO2, 0.54 ppm (range 0.00‐6.77) for SO2 and 29.64 ppm (range 0.00- 338.98) for CO. The number of households where standards were exceeded by the maximum hourly averages by NO2 and CO was six (9%) and 20 (30%) respectively (WHO standard) and for SO2 the number was 28 (42%) (Californian standard) (no WHO or USEPA standard for maximum hourly average for SO2 exists). TSP measures ranged from a minimum of 7.15 µg/m 3 to a maximum of