2006 ICD-9-CM Volume 1 Diagnosis Codes Home > Diseases Of The Respiratory System 460-519 > Pneumoconioses And Other Lung Diseases Due To External Agents 500-508 > ICD-9-CM Diagnosis 504 Pneumonopathy due to inhalation of other dust An airway obstruction due to the dust inhaled during the processing of cotton. 504 is a specific code that can be used to specify a diagnosis 504 contains 18 index entries