Assessment of patients with possible occupational asthma. Assessment of patients with possible occupational asthma. FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; PEF, peak expiratory flow; CXR, chest radiography; IIB, Industrial Injuries Benefit; HSE, Health & Safety Executive; RIDDOR, Reporting of Injuries, Diseases and Dangerous Occurrences Regulations. D Fishwick et al. Thorax 2008;63:240-250 Copyright © BMJ Publishing Group Ltd & British Thoracic Society. All rights reserved.