SmogRank / France / Pays de la Loire / Montoir-de-Bretagne

Montoir-de-Bretagne, month by month

Montoir-de-Bretagne has a measured daily mean on 146 days since 29 January 2024. Its worst month was February 2024, at 45 US AQI (8.1 µg/m³), 1,073rd of 2,486 cities on that month's world ranking. Its cleanest was April 2024, at 33 US AQI (6.0 µg/m³).

Every month since 2024

2026too few days for a mean (a year needs 200)51 days measured
Jan4 daysFebnoneMarnoneAprnoneMay4 daysJun3 daysJul13 daysAug8 daysSep12 daysOct7 days
2025too few days for a mean (a year needs 256)3 days measured
Jan3 daysFebnoneMarnoneAprnoneMaynoneJunnoneJulnoneAugnoneSepnoneOctnoneNovnoneDecnone
2024too few days for a mean (a year needs 257)92 days measured
Jan3 daysFeb45#1,073Mar14 daysApr33#1,678May21 daysJunnoneJulnoneAugnoneSepnoneOctnoneNovnoneDec1 day
Each square is a month's mean PM2.5 in US AQI from Montoir-de-Bretagne's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Montoir-de-Bretagne marked; each year, the year's.
Good0–50
Moderate51–100
Unhealthy for sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Months without a mean, and why

32 months
MonthWhy
Oct 20267 of 12 days measured; a month needs 9. The others: 2 with no readings from the monitor, 2 with readings for part of the day (a day needs 18 hours), 1 with under 18 hours of readings or readings that failed our checks.
Sep 202612 of 30 days measured; a month needs 21. The others: 18 with under 18 hours of readings or readings that failed our checks.
Aug 20268 of 31 days measured; a month needs 22. The others: 23 with under 18 hours of readings or readings that failed our checks.
Jul 202613 of 31 days measured; a month needs 22. The others: 18 with under 18 hours of readings or readings that failed our checks.
Jun 20263 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks.
May 20264 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks.
Apr 2026No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Mar 2026No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Feb 2026No day measured. The others: 28 with under 18 hours of readings or readings that failed our checks.
Jan 20264 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks.
Dec 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 2025No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 2025No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Aug 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jul 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jun 2025No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
May 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Apr 2025No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Mar 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Feb 2025No day measured. The others: 28 with under 18 hours of readings or readings that failed our checks.
Jan 20253 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks.
Dec 20241 of 31 days measured; a month needs 22. The others: 30 with under 18 hours of readings or readings that failed our checks.
Nov 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Aug 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jul 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jun 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
May 202421 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks.
Mar 202414 of 31 days measured; a month needs 22. The others: 17 with under 18 hours of readings or readings that failed our checks.
Jan 20243 of 31 days measured; a month needs 22.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Montoir-de-Bretagne's worst months

MonthUS AQIDays measuredWorld rank
February 2024 458.1 µg/m³26 of 291,073rdof 2,486
April 2024 336.0 µg/m³27 of 301,678thof 2,520

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Montoir-de-Bretagne's worst days

DayUS AQI
28 Dec 2024 7119.9 µg/m³
8 Feb 2024 6717.9 µg/m³
4 Feb 2024 6717.8 µg/m³
25 Apr 2024 6013.7 µg/m³
12 May 2024 5813.1 µg/m³
29 May 2026 5712.3 µg/m³
7 Feb 2024 5612.0 µg/m³
9 May 2024 5611.7 µg/m³
28 May 2026 5611.7 µg/m³
31 Jan 2024 5511.4 µg/m³

Daily means, the highest since 29 Jan 2024; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Montoir-de-Bretagne, France, 29 Jan 2024 – 12 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/fr/montoir-de-bretagne/history (accessed 13 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Montoir-de-Bretagne now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-13 03:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).