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Wildfire smoke EPA monitor flag

2007-02-11 wildfire smoke episode affecting Deltona-Daytona Beach-Ormond Beach, FL

February 11, 2007

Daily PM2.5 peaked at 24 µg/m³ near Deltona across 1 covered metro home to 739,516 people.

Why we think this happened

The basis for “Wildfire smoke”

Qualified frozen causal evidence supports wildfire smoke as the broad root cause.

EPA monitor flag EPA attached an exceptional-event qualifier to the affected samples. The agency flagged the measurement itself; no separate agency record describes the event.

U.S. EPA Air Quality System and the submitting air monitoring agency · Feb 11, 2007 official

AQS PM2.5 qualifier RT — Wildfire-U. S.

EPA AQS carries an agency-submitted request-exclusion qualifier (RT, Wildfire-U. S.) on 1 PM2.5 sample in the candidate CBSA on 2007-02-11, identifying wildfire smoke as affecting the sample. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.

See every retained source and limitation ↓

Evidence path

From source to city

A cause is more convincing when the record connects three things: something happened, the air mass moved toward the region, and local instruments responded. Here is how much of that chain is documented for this event.

Open the evidence ledger ↓
  1. 1

    Source or mechanism

    Wildfire smoke

    EPA AQS carries an agency-submitted request-exclusion qualifier (RT, Wildfire-U. S.) on 1 PM2.5 sample in the candidate CBSA on 2007-02-11, identifying wildfire smoke as affecting the sample. A request-exclusion qualifier is an official…

    View supporting source ↗
    Documented
  2. 2

    Air-mass movement

    The transport path has not been reconstructed

    The retained record does not yet show how air traveled from the proposed source to these metros. A trajectory replay or dated plume analysis belongs here.

    Research gap
  3. 3

    Local response

    24 µg/m³ near Deltona

    EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 1.1 cigarette-equivalents at the outdoor daily rate.

    Inspect the pollutant and weather signals ↓
    Documented

Event autopsy

What the instruments saw

Before, during, and after the episode: nearby pollutant monitors and surface-weather stations show what changed. This context tests the “Wildfire smoke” explanation; it does not assign the cause by itself.

Observed context · not attribution

Deltona-Daytona Beach-Ormond Beach, FL

Monitor comparison window 2007-02-08 to 2007-02-14 · PM2.5 target: DAYTONA BLIND SERVICES

3 pollutant signals
Fine-particle pulse 24 µg/m³

53% above nearby days

PM10 26 µg/m³

8% higher than surrounding days

Pollution fingerprint

Metro-wide median of reporting monitors
PM2.5 24 µg/m³

53% higher than surrounding days

Before15.7 µg/m³ Event24 µg/m³ After6.50 µg/m³
1 monitor · 24 HOUR
PM10 26 µg/m³

8% higher than surrounding days

Before35 µg/m³ Event26 µg/m³ After13 µg/m³
1 monitor · 24-HR BLK AVG
Ozone 0.034 ppm

12% higher than surrounding days

Before0.030 ppm Event0.034 ppm After0.020 ppm
2 monitors · 8-HR RUN AVG BEGIN HOUR

Source: U.S. EPA AirData daily observations and, where available, nearby ASOS/AWOS surface observations. Values are descriptive medians over the retained monitor set; missing measurements remain missing. Transport and source evidence remain separate layers because this instrument pattern does not assign a cause by itself.

Measured daily PM2.5 at EPA monitors, as cigarette-equivalents
EPA monitors sit in metro areas, so the colour clusters there. Land between and beyond them is unmeasured, not clean: this map shows where IAQng has readings, not the extent of the smoke.

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.

Affected metros

MetroPeak PM2.5Cigarettes, whole eventPeak dayAll-time standing
Deltona-Daytona Beach-Ormond Beach, FL 24 µg/m³ 1.1 Feb 11, 2007 #21 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.

Public evidence library

What supports this account

Each card states what a source supports—and what it does not. Official records, research, reporting, community observations, and transparent inferences remain visibly different kinds of evidence.

EPA AQS monitor qualifier 1

  • AQS PM2.5 qualifier RT — Wildfire-U. S.

    U.S. EPA Air Quality System and the submitting air monitoring agency · Feb 11, 2007 official government

    EPA AQS carries an agency-submitted request-exclusion qualifier (RT, Wildfire-U. S.) on 1 PM2.5 sample in the candidate CBSA on 2007-02-11, identifying wildfire smoke 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

Status and provenance

EPA monitor flag EPA attached an exceptional-event qualifier to the affected samples. The agency flagged the measurement itself; no separate agency record describes the event.

This episode was grouped from the monitor record by the catalog pipeline and given its cause from the evidence listed above. It has not been individually reviewed and signed off, so its boundaries, cause, and name may change as evidence accumulates. Grouping policy common_sense_root_cause_grouping.v2. The cause label reflects the assembled evidence above, not an IAQng detection formula. If it is wrong, tell us.