In the figures presented, typical examples of the daily evolution of the pollutants measured in
the living room and the kitchen are given. In figure 1, the distribution of total VOCs in the living
is presented for 11/2/06 (Saturday). A double morning peak (2400 µg m-3) appears around
9:00 LST and 12:00 LST which may be attributed to opening of the windows, cleaning and
cooking activities in the flat. Concentrations then decrease to 450 µg m-3 until 18:30 LST
where the inhabitants gather in the living room smoking a number of cigarettes and values
reach 4400 µg m-3 (22:00 LST). Concentrations then drop gradually to background levels (of
the order of 400 µg m-3) after 22:00 LST even though smoking ceased at around 21:00 LST.
CO2 concentrations for the same day follow approximately the same pattern as the total
VOCs commencing with 1200 mg m-3 in the morning and then dropping to 800 mg m-3 at
around 12:00 LST. The concentrations then reach a maximum value of 2600 mg m-3 at 20:00
LST, sooner than the total VOCs do, while the inhabitants are smoking. After 21:00 LST CO2
concentrations return to their morning background levels (Figure 2).