Transport workers, subjected to variable direct exposure to allergens in the workplace, are an occupational group at risk of developing occupational allergic diseases of the respiratory system as well as the skin. Their work environment is characterized by considerable diversity of both chemical and biological sensitizers. Sensitization occurs due to occupational exposure to allergens mainly by inhalation or direct skin contact. Therefore, it is necessary to be aware of the presence of strong allergens in the work environment to introduce appropriate preventive measures and to reduce the adverse health effects resulting from the exposure. This publication presents the most important allergens described as causal factors of occupational allergy among transport workers and the basic principles of diagnostics and medical certification of these diseases. Med Pr 2011;62(6):633-641