Three categories of rhinitis may occur in the workplace: occupational rhinitis, work-aggravated rhinitis and rhinitis-like conditions. In the present paper, we propose a new definition and a new classification of occupational rhinitis that takes into account mechanisms of induction as well as clinical presentation. In parallel with occupational asthma, occupational rhinitis is defined as a type of rhinitis characterized by intermittent or sometimes permanent nasal airflow limitation due to causes and conditions attributable to the work environment. Occupational rhinitis is classified according to its mechanism of induction as immunological or irritant-induced (non-immunological) rhinitis. Occupational rhinitis of the immunological type can itself be episodic or persistent, whereas the non-immunological type is subdivided into acute, chronic and corrosive.