xmlns:atom="http://www.w3.org/2005/Atom"
2.1 In this Part, percentiles are to be calculated using the method specified in Council Decision 97/101/EC establishing a reciprocal exchange of information and data from networks and individual stations measuring ambient air pollution within the Member States(1).
2.2 The following criteria are to be used for checking validity when aggregating data and calculating statistical parameters:–
Parameter | Required proportion of valid data |
---|---|
(1)
| |
1 hour values | 75% (45 minutes) |
8 hour values | 75% of values (6 hours) |
Maximum daily 8 hours mean from hourly running 8 hours averages | 75% of the hourly running 8 hour averages (8 hours per day) |
AOT40 | 90% of the 1 hour values over the time period defined for calculating the AOT40 value (1) |
Annual mean | 75% of the 1 hour values over summer (April to September) and winter (January to March, October to December) seasons separately |
Number of exceedances and maximum values per month | 90% of the daily maximum 8 hours mean value (27 available daily values per month) 90% of the 1 hour values between 0800 and 2000 Central European Time |
Number of exceedances and maximum values per year | Five out of six summer months over the summer season (April to September) |
O.J. No. L 035, 5.2.97, p.14.