Duration of employment

No

FVC in Litre

FVC%

FEV1 in Litre

FEV1%

PEFR Litre/Sec

<12 month

43

3.93 ± 0.39

90.60 ± 5.49

2.98 ± 0.59

77.09 ± 13.17

7.15 ± 1.10

12 - 17 months

39

3.87 ± 0.35

86.26 ± 7.39

2.56 ± 0.66

66.15 ± 17.18

6.68 ± 1.09

≥18 months

26

3.97 ± 0.61

86.88 ± 10.81

2.35 ± 0.78

59.62 ± 18.64

6.60 ± 0.97

F-ratio

0.39

3.691

8.063

10.466

2.89

p value

0.679

0.028

0.001

0.0001

0.0001