Isocyanates can present respiratory hazards as particulates, vapors or aerosols. Autobody shop workers are a very commonly examined population for isocyanate exposure as they are repeatedly exposed when spray painting automobiles and can be exposed when installing truck bed liners. Hypersensitivity pneumonitis has slower onset and features chronic inflammation that can be seen on imaging of the lungs. Occupational asthma is a worrisome outcome of respiratory sensitization to isocyanates as it can be acutely fatal. Diagnosis of occupational asthma is generally performed using pulmonary function testing (PFT) and performed by pulmonology or occupational medicine physicians. Occupational asthma is much like asthma in that it causes episodic shortness of breath and wheezing. Both the dose and duration of exposure to isocyanates can lead to respiratory sensitization. Dermal exposures to isocyanates can sensitize an exposed person to respiratory disease.
Dermal exposures can occur via mixing, spraying coatings or applying and spreading coatings manually. Dermal exposures to isocyanates is known to lead to respiratory sensitization. Even when the right personal protective equipment (PPE) is used, exposures can occur to body areas not completely covered. Isocyanates can also permeate improper PPE, necessitating frequent changes of both disposable gloves and suits if they become over exposed.