Prevalence of Occupational Asthma and Respiratory Symptoms in Foundry Workers

Table 2

The number of workers with occupational asthma and airway obstruction (based on FEV₁).

Working department	OA (%)	Decrease in FEV1 (% of predicted)
		Mild	Moderate	Severe
Production department (𝑛=286)	48 (16.78%)*	5	38	5
Nonproduction department (𝑛=61)	3 (4.91%)	—	3	—
Total (𝑛=347)	51 (14.69%)	5	41	5

OA: occupational asthma; the airway obstruction was classified according to forced expiratory volume in one second (FEV₁, % of predicted) results and divided into 3 groups as mild (>79%), moderate (60–79%), and severe (40–59%).
∗P = 0.001 compared to non-production department.