# The Air Quality Standards Regulations (Northern Ireland) 2010, Schedule 5: Information and alert thresholds

Extent: N.I.

Alert thresholds for Sulphur dioxide and Nitrogen dioxide
Pollutant
Alert threshold
(1)To be measured over three consecutive hours at locations representative of air quality over the least 100 km2 or an entire zone, whichever is smaller.
Sulphur dioxide
500 µg/m3
Nitrogen dioxide
400 µg/m3
Information and alert thresholds for Ozone
Purpose
Averaging period
Threshold
Information
1 hour
180 µg/m3
Alert
1 hour
240 µg/m3

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Source: https://www.legislation.gov.uk/nisr/2010/188/schedule/5 (the official version)
Page: https://openlegislation.uk/air-quality-standards-regulations-northern-ireland-2010/schedule-5
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.