SmogRank / Italy / Campania / Acerra

Acerra, month by month

Acerra has a measured daily mean on 434 days since 11 January 2023. Its worst month was February 2024, at 83 US AQI (26.5 µg/m³), 130th of 2,486 cities on that month's world ranking. Its cleanest was April 2025, at 53 US AQI (10.3 µg/m³).

Every month since 2023

2026too few days for a mean (a year needs 199)154 days measured
Jan3 daysFebnoneMar2 daysApr62#578May54#689Jun19 daysJul63#496Aug70#260Sep18 daysOct63#200
2025too few days for a mean (a year needs 256)118 days measured
JannoneFebnoneMar2 daysApr53#1,108May14 daysJun11 daysJul16 daysAug62#363Sep14 daysOct4 daysNovnoneDecnone
2024too few days for a mean (a year needs 257)106 days measured
Jan3 daysFeb83#130Mar10 daysApr61#432May66#202Jun12 daysJulnoneAugnoneSepnoneOctnoneNovnoneDecnone
2023too few days for a mean (a year needs 256)56 days measured
Jan7 daysFeb80#55Mar20 daysApr3 daysMaynoneJunnoneJul1 dayAugnoneSepnoneOctnoneNovnoneDecnone
Each square is a month's mean PM2.5 in US AQI from Acerra'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 Acerra marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
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

35 months
MonthWhy
Sep 202618 of 30 days measured; a month needs 21. The others: 12 with readings for part of the day (a day needs 18 hours).
Jun 202619 of 30 days measured; a month needs 21. The others: 11 with under 18 hours of readings or readings that failed our checks.
Mar 20262 of 31 days measured; a month needs 22. The others: 29 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 20263 of 31 days measured; a month needs 22. The others: 28 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 20254 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks.
Sep 202514 of 30 days measured; a month needs 21. The others: 16 with under 18 hours of readings or readings that failed our checks.
Jul 202516 of 31 days measured; a month needs 22. The others: 15 with under 18 hours of readings or readings that failed our checks.
Jun 202511 of 30 days measured; a month needs 21. The others: 19 with under 18 hours of readings or readings that failed our checks.
May 202514 of 31 days measured; a month needs 22. The others: 17 with under 18 hours of readings or readings that failed our checks.
Mar 20252 of 31 days measured; a month needs 22. The others: 29 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 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Dec 2024No day measured. The others: 31 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 202412 of 30 days measured; a month needs 21. The others: 18 with under 18 hours of readings or readings that failed our checks.
Mar 202410 of 31 days measured; a month needs 22. The others: 21 with under 18 hours of readings or readings that failed our checks.
Jan 20243 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks.
Dec 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 2023No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 2023No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Aug 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jul 20231 of 31 days measured; a month needs 22. The others: 30 with under 18 hours of readings or readings that failed our checks.
Jun 2023No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
May 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Apr 20233 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks.
Mar 202320 of 31 days measured; a month needs 22. The others: 11 with under 18 hours of readings or readings that failed our checks.
Jan 20237 of 31 days measured; a month needs 22. The others: 14 with under 18 hours of readings or readings that failed our checks.

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

Acerra's worst months

MonthUS AQIDays measuredWorld rankEpisode
February 2024 8326.5 µg/m³28 of 29130thof 2,486Europe, 27 January to 2 February 2024
February 2023 8024.7 µg/m³25 of 2855thof 1,129Europe, 6 to 25 February 2023
Campania, Apulia and The Marches, Italy, February 2023
August 2026 7019.2 µg/m³30 of 31260thof 2,896–
May 2024 6617.3 µg/m³29 of 31202ndof 2,684The Marches, Campania and Trentino-Alto Adige, Italy, May 2024
July 2026 6315.4 µg/m³29 of 31496thof 2,784–
August 2025 6214.9 µg/m³30 of 31363rdof 2,901–

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.

Acerra's worst days

DayUS AQIEpisode
13 Jan 2023 16069.0 µg/m³–
2 Feb 2023 15358.0 µg/m³–
18 Feb 2024 15156.1 µg/m³–
17 Feb 2024 15155.6 µg/m³–
1 Feb 2024 13850.7 µg/m³Europe, 27 January to 2 February 2024
23 Jan 2026 13850.7 µg/m³–
31 Jan 2024 13649.9 µg/m³Europe, 27 January to 2 February 2024
12 Feb 2023 13449.1 µg/m³Europe, 6 to 25 February 2023
11 Jan 2023 12143.8 µg/m³–
3 Feb 2023 11943.0 µg/m³–

Daily means, the highest since 11 Jan 2023; 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, Acerra, Italy, 11 Jan 2023 – 11 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/it/acerra/history (accessed 12 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.

Acerra now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 19:07 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).