[Risk of chronic carbon monoxide poisoning in automobile garages. Results of a study in the Lausanne region].

Clinical and physiologic data on chronic carbon monoxide poisoning are reviewed and the results of an investigation involving 7 garages in the Lausanne (Switzerland) area are reported. The aim was a practical approach to the relationships between carbon monoxide level in the air, COHb and clinical picture. The study covered working conditions (especially ventilation) but did not take into account of other factors (stresses) which may effect the parameters investigated. CO was measured by continuous recording with an MSA Carbon Monoxide Alarm and the hourly and daily averages were determined. The garage personnel replied to a questionnaire and underwent a brief clinical examination including taking of digital blood samples for measurement of hematocrit and carboxyhemoglobin level by the method of COMMINS and LAWTHER as modified by BUCHWALD. One of the garages did not meet present health requirements. Statistical analysis revealed a significant correlation between carbon monoxide and carboxyhemoglobin. The incidence of complaints was highest in poorly ventilated garages. On the basis of COHb level in the total group of employees, together with data from individual histories, it is possible to evaluate the risk of carbon monoxide poisoning in a given garage.