© Christian Widmann
The team conducted a large real-world in-vehicle personal exposure study by monitoring 141 drivers’ exposure to black carbon. The professional drivers, which included taxi drivers; couriers; waste removal, heavy freight and bus drivers; utility services; passenger transport; and emergency services, were based within London, and were monitored for four working days. A follow-up intervention study of 42 drivers was also conducted to assess the effectiveness of using in-cabin filters to reduce drivers’ exposure.
There is no applicable ambient standard for black carbon. However, with black carbon being a component of fine particulate matter (PM2.5), the closest applicable ambient standard is the World Health Organisation (WHO) ambient air quality guideline for PM2.5, which is set at 25 μg/m3 averaged over 24 hours.
In the study, there was only one instance when a participant was over the 24-hour WHO PM2.5 guideline (black carbon at 30.9 μg/m3), but short-term exposures were intermittently higher than this value, flagging the importance of employers with professional drivers to consider, monitor and act on reducing the risks to their employees.
The study published in 2020 recommends that both employers and drivers change behaviours to help facilitate a reduction. It goes on to conclude that the most effective way to reduce (professional) drivers’ exposures to diesel exhaust concern the technical level (change to zero tailpipe emission, vehicles with airtight cabins etc.).
Full text of the study: https://iosh.com/media/8902/the-driver-diesel-exposure-mitigation-study-full-report.pdf
Mary Ogungbeje
Mary.Ogungbeje@iosh.com