# Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe, Division B: Information and alert thresholds for ozone

Extent: E+W+S+N.I.

For the implementation of Article 24, the exceedance of the threshold is to be measured or predicted for three consecutive hours.
Purpose
Averaging period
Threshold
Information
1 hour
180 μg/m3
Alert
1 hour
240 μg/m3

---
Source: https://www.legislation.gov.uk/eudr/2008/50/annex/XII/division/B (the official version)
Page: https://openlegislation.uk/eu-directive-2008-50/annex-XII/division-B
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.