The objective of this study is determination of occupational asthma prevalence in steel factory and classification of cases according to various workshops.

Occupational Asthma is characterized by reversible airway obstruction, either spontaneously or with treatment, airway inflammation and increased airway responsiveness due to workplace exposure. It is the most common occupational lung disease in developed countries. One of causative agent is metal fume that may be encountered in steel industries. In this study we determined occupational asthma prevalence in one steel factory and then we classified results according to various workshops.

In this cross sectional study we determined workshops for 450 workers of steel industry by questionnaire. Then cross shift spirometry was done in all of them.

In cross shift spirometry we detected 14 occupational asthma cases. Highest prevalence was in catering (25%) and other workshops according to prevalence were welding (10%), construction (7%), scrap (5%), roller and lathes and melting (3%).

There is great variability for occupational asthma in different workshops of steel industry. Highest prevalence was in catering that its exposures is different from other workshops in steel industry. It seems that this kind of exposures is more asthmogen than metal fumes