Home oxygen therapy has been used to provide symptomatic relief of breathlessness for more than 20 yr. Continuous low-flow oxygen can improve exercise tolerance and decrease pulmonary hypertension in patients suffering from chronic obstructive airway disease. The majority of these patients have been long-time smokers. Despite routine warnings about potential dangers, a considerable number of patients will continue to smoke whilst on oxygen. The incidence of burn injuries related to this practice is not known. Reports of such incidents are, however, very rare. Twenty-one patients who sustained head and neck burn injuries secondary to cigarette related ignition of their oxygen delivery system were admitted to our burn unit over a 7-yr period (1990-1997). All patients (mean age 60.4 yr) had been informed about the associated risks but did not shut off their supplemental oxygen system during smoking. The mean size of their burn injuries was 2% of the total body surface, mainly affecting the face, ears, and neck. The average duration of the hospital stay was 3.6 days. Two patients required split-thickness skin grafting. Whether chronically ill patients on domiciliary oxygen who continue to smoke covertly are amenable to medical advice to abandon this habit is questionable. A more aggressive education about the explosive nature of their activity should help to prevent them from using tobacco and oxygen at the same time.