Pic of pollution to desert dust: information procedure-recommendation in Isère

Background

PM10 levels were gradually increasing in recent days due to desert dust fallout. The procedure applies only to municipalities belonging to the Grenoblais and Lyon Nord-Isère airsheds. It relies on a zonal decree of 2024 and prefectural decrees of 2025.

Why it's important

Pollution episodes primarily affect sensitive and vulnerable people, including children, the elderly and people with respiratory diseases. Understanding the difference between the information-recommendation and the alert makes it possible to react proportionately. This is a typical example of local prefectural communication.

What Changes

With the activation of the procedure, the prefecture makes recommendations and not prohibitions: only the intense physical activities in the open air of vulnerable people are concerned.

Useful details

• Cause of the episode: dust deposition of desert origin, with a gradual increase in fine PM10 particles.
• End of the episode scheduled on Friday 28/08/2026.
• The procedure activated is information-recommendation, not alert: no mandatory action is required.
• Recommendations for sensitive and vulnerable people: to limit outings and intense physical and sporting activities in the open air (including competitions); indoor activities can be maintained.
• For the population as a whole: there is no need to change the activities, movements or usual ventilation and ventilation practices; the situation does not justify containment measures.
• Regulatory basis: Zonal Order No. 69 - 2024 - 02 - 12 - 00007 of the 12 / 02 / 2024 ; prefectural decrees of Isère No. 38 - 2025 - 01 - 16 - 00016 of the 16 / 01 / 2025 , as amended by Order No. 38 - 2025 - 01 - 17 - 00004 of the 17 / 01 / 2025 .