Other
1999-10-14 other documented PM source or accumulation mechanism episode affecting Columbus, OH
Daily PM2.5 peaked at 157.1 µg/m³ near Columbus across 1 covered metro home to 2.2 million people. 1 metro placed a top-ten day in their record.
Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 6.7 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 15 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.
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
Qualified frozen evidence supports other documented PM source or accumulation mechanism as the broad root cause.
Affected metros
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Columbus, OH | 157.1 µg/m³ | 7.1 | Oct 14, 1999 | #2 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 RP — Structural Fire. EPA AQS carries an agency-submitted request-exclusion qualifier (RP, Structural Fire.) on 1 PM2.5 sample in the candidate CBSA on 1999-10-14, identifying a structural fire as affecting the sample. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.
What remains uncertain
- AQS qualifiers are submitting-agency causal flags and do not by themselves establish EPA concurrence.
- The retained evidence does not map the documented mechanism to a more specific catalog cause type.
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.