Indoor car parks, occupational risks

In its 2007 report on air quality in indoor car parks, the Agency considered that the health risks could not "be regarded as negligible given the concentrations of pollutants measured in the four car parks investigated and what is known of their acute and chronic toxic effects”, especially for professionals working in areas of vehicle traffic. One of the recommendations thus sought to "improve characterisation of exposed populations (workers and users) and their patterns of exposure, in particular the duration".
Following on from this work, in April 2008 the Agency received a formal request from the Ministry of Labour. Considering the results of the previous expert appraisal on indoor car parks, the regulatory context, the diversity of occupations related to indoor car parks and the expected increase in the number of operators working in these structures, the Directorate General for Labour sought in particular to obtain:

• characterisation of occupational activities: identification, duration and frequency of work, prevalence within indoor car parks and number of workers;
• assessment of the health risks associated with occupational activities in indoor car parks, and in particular identification of the highest risk occupational activities and the most problematic pollutants, in order to provide recommendations on prevention.

Results and recommendations

The results of this work were published in July 2010. Based on its analysis, the Agency concluded in particular that professionals working regularly in indoor car parks are exposed to health risks related to the levels of air pollution in the car parks. The risks associated with acute (short-term) exposure are due in particular to carbon monoxide (effects related to a decrease in available oxygen in the blood) and nitrogen dioxide (effects on the respiratory system, especially among the most susceptible subjects, asthmatics in particular). The risks associated with chronic (long-term) exposure are mainly due to benzene (a category 1 carcinogen) and nitrogen dioxide, and to a lesser extent, fine particulate matter (PM10) (effects on the respiratory and cardiovascular systems) and formaldehyde (eye and nasal irritation).

Among the activities studied, car park operations (reception, surveillance, maintenance) and cleaning of vehicles seem to result in the highest exposure. Overall, these two activities involve the longest working hours and therefore the highest exposure in car parks.

These results led ANSES to make the following recommendations:

• improve and assess air quality in indoor car parks, particularly by implementing the recommendations given in the Opinion of 20 April 2007, and specifically by setting limit values proposed for the NO (nitrogen monoxide) atmospheric pollution indicator;
• do not authorise activities that are not essential to the car parks’ operation and that involve workers being in areas with insufficient air quality (underground levels, levels without large openings to the outside, or even underground rooms equipped with independent mechanical ventilation);
• reduce as far as possible the exposure of workers performing activities that are vital to car park operations (reception, surveillance, maintenance of facilities);
• review as a priority the occupational exposure limits (OELs) for pollutants of interest in indoor car parks (benzene, nitrogen dioxide, carbon monoxide);
• reinforce monitoring and supervision of occupational activities in indoor car parks.