Definition of the scenarios Sample Clauses

Definition of the scenarios. The choice of a scenario of change in air pollution levels is a key step in the HIA process, and different scenarios can be considered to calculate this change. Two types of scenarios can be distinguished: - scenarios where the concentrations are decreased by a fixed amount, for instance a decrease by 5 µg/m3 - scenarios where the concentrations are decreased to reach a specific value, for instance a decrease to reach the WHO air quality guidelines value. In Aphekom, we applied scenarios using a fixed decrease in the concentrations, and decreasing the concentration to the WHO air quality guidelines. Scenarios are reported in Table 2. Table 2: Scenarios used in the Aphekom HIA HIA Scenario Short-term impacts of PM10 Scenario 1: Decrease by 5 µg/m3 Scenario 2: Decrease to the WHO air quality guidelines (WHO-AQG) of 20 µg/m3 Short-term impacts of Ozone Scenario 1: All daily maximum values exceeding 160 µg/m3 are decreased to the WHO-AQG of 160 µg/m3 Scenario 2: All daily maximum values exceeding 100 µg/m3 are decreased to the WHO-AQG of 100 µg/m3 Scenario 3: Annual mean decreased by 5 µg/m3 Long-term impacts of Ozone Decrease by 5 µg/m3 in the April-September average levels Long-term impacts of PM2.5 Scenario 1: Decrease by 5 µg/m3 Scenario 2: Decrease to the WHO air quality guidelines (WHO-AQG) of 10 µg/m3 In practice - Define the scenarios consistently with the local needs and interests