In the air quality directive (2008/EC/50), the EU has set a limit value for carbon monoxide (CO) for the protection of human health: the CO maximum daily 8-hour mean values may not exceed 10 milligrams per cubic metre (mg/m3).
EEA standard re-use policy: unless otherwise indicated, re-use of content on the EEA website for commercial or non-commercial purposes is permitted free of charge, provided that the source is acknowledged (http://www.eea.europa.eu/legal/copyright). Copyright holder: European Environment Agency (EEA).
Keep your dog on a lead if it is likely to run off and disturb wildlife.
In particular, be careful of nesting birds in early spring and early summer, and roosting or feeding birds in winter. If you have a dog, keep this in mind when you're taking it for a walk!
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