Abstract
Accurate diagnosis of occupational asthma takes time, enthusiasm and a particular knowledge of the work situation, as well as expertise in the use of diagnostic procedures. The prognosis of patients with occupational asthma is probably improved by removing them from the responsible agent as soon as possible after sensitization occurs. However, it is much easier to make the diagnosis while the worker is still exposed to the cause of the problem. Early referral for expert investigation is therefore important.