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Wildfire smoke

2025-08-05 wildfire smoke episode affecting Hartford-West Hartford-East Hartford, CT, Springfield, MA

August 5, 2025

Daily PM2.5 peaked at 45.9 µg/m³ near Hartford across 2 covered metros home to 1.6 million people.

Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 1.7 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 2.8 million cigarettes. An awareness illustration of outdoor exposure at 22 µg/m³ per cigarette (Berkeley Earth), counting only the event's ranked days; not a medical dose.

Measured daily PM2.5 at EPA monitors, as cigarette-equivalents

Episode peak

-- cigarettes

The smoke map's scale, replayed over this event: the surface interpolates between covered metros' daily records, framed to the affected region. Hover for a reading, click a metro to pin it to the card. Days a monitor did not report draw nothing.

What happened, in the record

The supplied retained evidence supports wildfire smoke for this event; no supplied evidence establishes membership in a broader time-bounded episode.

Sequence: Hartford (Aug 5) → Springfield (Aug 5)

Affected metros

MetroPeak PM2.5Cigarettes, whole eventPeak dayAll-time standing
Hartford-West Hartford-East Hartford, CT 45.9 µg/m³ 2.1 Aug 5, 2025 #15 of its top days
Springfield, MA 45 µg/m³ 2.0 Aug 5, 2025 #23 of its top days

"Cigarettes, whole event" totals a metro's ranked event days at 22 µg/m³ per cigarette: what a person outdoors there breathed across the event, as the illustration. "All-time standing" is where this episode's days sit in each metro's ranked record (worst-area measure, since 1999). Full local context is on each metro's Air Records page.

The evidence

EPA AQS monitor qualifier 1

  • AQS PM2.5 qualifier IF — Fire - Canadian. U.S. EPA Air Quality System and the submitting air monitoring agency, Aug 5, 2025 · official EPA AQS carries an agency-submitted informational qualifier (IF, Fire - Canadian.) on 57 PM2.5 samples in the candidate CBSA on 2025-08-05, identifying wildfire smoke as affecting the samples. An informational qualifier is an official submitting-agency flag, not a request for exclusion or an EPA-concurred determination.

Agency and publisher pages 1

Status and provenance

Research preview: this record carries research-only status and its boundaries, cause, and name may change as evidence review completes. Grouping policy common_sense_root_cause_grouping.v2. The cause label reflects the assembled evidence above, not an IAQng detection formula.