Time series of particles number concentrations measured during the chamber experiments.

<p>a) Cigarette smoke particles in the size fraction: M1 ≤ 2.5 μm, M2 ≤ 2.5 μm, OPC ≤ 2.1 μm and SMPS = total PNC. b) Cigarette smoke particles in the size fraction: M1 ≤ 10 μm, M2 ≤ 10, OPC ≤ 7 μm and APS = total PNC. c) Petrol exhaust particles in the size fraction: M1 ≤ 2.5 μm, M2 ≤ 2.5 μm, OPC ≤ 2.1 μm and SMPS = total PNC. d) Petrol exhaust particles in the size fraction: M1 ≤ 10 μm, M2 ≤ 10 μm, OPC ≤ 7 μm and APS = total PNC. e) Concrete dust particles in the size fraction: M1 ≤ 2.5 μm, M2 ≤ 2.5 μm, OPC ≤ 2.1 μm and SMPS = total PNC. f) Concrete dust particles in the size fraction: M1 ≤ 10 μm, M2 ≤ 10 μm, OPC ≤ 7 μm and APS = total PNC. The black dotted vertical lines represent times at which the particles were introduced into the chamber.