. For the type of fuel used, the predominant fuel
used over the past year was considered. Those smoking >10
cigarettes or bidis per day for the last 20 years or more were
considered heavy smokers (smoking index of 20 pack-years).
Overcrowding was classified according to the number of persons
per room. Pulmonary function tests done for all the subjects
included forced vital capacity (FVC), forced expiratory volume in the
first second (FEV 1.0) and FEV 1.0/FVC. Three readings were
taken after explaining and demonstrating the test procedure. The
best of three readings was considered for analysis. The predicted
value of FEV 1.0 for the concerned population was calculated and
80% of the predicted value determined. The data of textile workers
were compared with control groups.