Prescribed fire
2024-04-05 Tulsa, OK and Wichita, KS prescribed-fire smoke episode
Daily PM2.5 peaked at 120.1 µg/m³ near Wichita across 2 covered metros home to 1.7 million people. 1 metro recorded their worst day on record.
Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 3.2 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 5.5 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 supplied evidence supports prescribed-fire smoke as the root cause of this event. The supplied record does not establish a coherent shared occurrence with neighboring candidates, so the episode remains event-specific.
Sequence: Wichita (Apr 5) → Tulsa (Apr 5)
Affected metros
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Wichita, KS | 120.1 µg/m³ | 7.1 | Apr 5, 2024 | Worst day on record |
| Tulsa, OK | 36.6 µg/m³ | 1.7 | Apr 5, 2024 | #18 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 2
- AQS PM2.5 qualifier IM — Prescribed Fire. EPA AQS carries an agency-submitted informational qualifier (IM, Prescribed Fire.) on 24 PM2.5 samples in the candidate CBSA on 2024-04-06, identifying prescribed-fire smoke as affecting the samples. An informational qualifier is an official submitting-agency flag, not a request for exclusion or an EPA-concurred determination.
- AQS PM2.5 qualifier IM — Prescribed Fire. EPA AQS carries an agency-submitted informational qualifier (IM, Prescribed Fire.) on 46 PM2.5 samples in the candidate CBSA on 2024-04-05, identifying prescribed-fire 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 2
- Flint Hills Wildland 2024 Summary The Kansas smoke-management summary records April 5 particulate impacts at the Wichita metro monitor during the Flint Hills burning season.
- Wichita air quality affected by smoke from range burning Contemporaneous Wichita reporting attributed degraded air quality to smoke from Flint Hills range burning, consistent with smoke transport into Wichita during the event.
Cited authorities: Kansas Department of Health and Environment
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.