Abstract
The prevalence and severity of byssinosis is studied in a sample of flax workers who had been exposed to dust for six months each year. Byssinosis prevails in 36.9% of the workers. Forced expiratory volume was reduced by 10% at the end of the first morning work period in 32.3% of the workers. Both syndromes are higher among seasonal workers than would be predicted if they were permanently exposed to flax dust.