Fig. 5
From: Second-hand smoke in four English prisons: an air quality monitoring study
Concentrations of PM2.5 sampled during a prison officer’s morning shift. Prison officer self-reported locations and duties during sampling: 08:40–10:00 Wing landing; supervising, dealing with prisoner queries; 10:00–10:10 Wing office; 10:10–11:00 Wing landing; including entering a prisoner cell; 11:00–11:50 Wing office; checking emails and paperwork; 11:50–12:40 Wing landing; supervising lunch time and locking up prisoners