Table 2.

The description of different scenarios. See Exposure scenarios sub-model -chapter for details.

	Scenario
	Current with traffic	Reduced traffic emissions	Current without traffic	Additional exposure
Follow-up period	Years 2002–2112
Population	Year 2002 Helsinki Metropolitan Area population
Primary PM2.5 health effects	Included in background mortality	Included in background mortality	Background mortality minus health effects of traffic related primary PM2.5 exposure	Background mortality plus health effects of additional 10 μgm-3 PM2.5 exposure
Primary PM2.5 exposure scenario	The actual 2002 exposure for 2002–2112	Actual 2002 exposure for 2002, then a gradual decrease of local traffic exposure until 2025; constant thereafter	No traffic exposure between 2002–2112	Actual 2002 exposure plus 10 μgm-3 for 2002–2112
Uncertainties in exposure taken into account	No	Yes	Yes	No