Abstract
A rating procedure for respiratory disability has been developed; it entails measuring the symptom-limited maximal oxygen uptake or estimating the maximal uptake from the results of a submaximal exercise test and other relevant variables. The derivation assumes a linear scale of disability between the limits 0% and 100% which are defined. The percentage disability of 157 men with respiratory limitation of exercise has been used to delineate empirical grades of disability. These are of similar form to those used for grading respiratory impairment. More information is needed with a view to validation.