It includes a wide range of conditions, of which some develop shortly after exposure, such as work-related asthma and legionella infections. Others develop many years later, such as pneumoconiosis, chronic obstructive pulmonary disease (COPD), lung cancer and pleural mesothelioma - these are life-limiting and/or life-altering.

It can occur in most industry sectors and is caused by a wide range of agents, from biological organisms through to dusts, fumes and vapours. Asbestos and respirable crystalline silica (RCS) are particularly substantial contributors to the burden of lung disease.