ZIP 21771 recorded 253 fire and hazmat incidents in 2025, 1,108 across 2021–2025. Primary county: Carroll County, MD.
1,108 incidents from 2021 through 2025 inside this ZIP.
| Year | Incidents | |
|---|---|---|
| 2021 | 199 | |
| 2022 | 203 | |
| 2023 | 227 | |
| 2024 | 226 | |
| 2025 | 253 |
Mar peaks. Oct dips. Aggregated across all 5 years inside this ZIP.
Top 5 NFIRS incident types for ZIP 21771 across 2021–2025.
| # | Incident type | Count | Share | |
|---|---|---|---|---|
| 1 | Power line down | 193 | 17.4% | |
| 2 | Gas leak (natural gas or LPG) | 151 | 13.6% | |
| 3 | Building fires | 149 | 13.4% | |
| 4 | Passenger vehicle fire | 60 | 5.4% | |
| 5 | Brush, or brush and grass mixture fire | 56 | 5.1% |
For the 34 building fires reported here in 2025, here's how investigators classified ignition cause.
NFIRS Area of Origin for ZIP 21771 fires across 2021–2025.
| # | Area of origin | Count | Share | |
|---|---|---|---|---|
| 1 | Outside area, other | 43 | 15.8% | |
| 2 | Engine area, running gear, wheel area | 39 | 14.3% | |
| 3 | Undetermined | 33 | 12.1% | |
| 4 | Cooking area, kitchen | 18 | 6.6% | |
| 5 | Other | 16 | 5.9% | |
| 6 | Open area - outside; included are farmland, field | 16 | 5.9% | |
| 7 | Wildland, woods | 14 | 5.1% | |
| 8 | Vehicle area, other | 11 | 4.0% | |
| 9 | All other areas | 83 | 30.4% |
NFIRS HEAT_SOURC code — the physical thing that started the fire.
| # | Heat source | Count | Share | |
|---|---|---|---|---|
| 1 | Undetermined | 115 | 42.1% | |
| 2 | Hot ember or ash | 26 | 9.5% | |
| 3 | Heat source: other | 24 | 8.8% | |
| 4 | Heat from powered equipment, other | 20 | 7.3% | |
| 5 | Radiated, conducted heat from operating equipment | 14 | 5.1% | |
| 6 | Arcing | 11 | 4.0% | |
| 7 | Hot or smoldering object, other | 11 | 4.0% | |
| 8 | Spark, ember or flame from operating equipment | 9 | 3.3% | |
| 9 | All other sources | 43 | 15.8% |
Largest single-incident losses in ZIP 21771 across 2021–2025. These 8 fires alone account for 706% of the ZIP's 2025 reported total.
| # | Property loss | Type | Year | Severity |
|---|---|---|---|---|
| 1 | $500,000 | Building fires | 2024 | Major |
| 2 | $200,000 | Building fires | 2022 | Significant |
| 3 | $150,000 | Building fires | 2023 | Significant |
| 4 | $100,000 | Building fires | 2022 | Significant |
| 5 | $100,000 | Building fires | 2022 | Significant |
| 6 | $100,000 | Building fires | 2025 | Significant |
| 7 | $70,000 | Road freight or transport vehicle fire | 2021 | Significant |
| 8 | $50,000 | Building fires | 2024 | Significant |
Some ZIPs span multiple cities. Ranked by 5-yr NFIRS incidents inside ZIP 21771.
| # | City | 5-yr incidents | |
|---|---|---|---|
| 1 | Mount Airy | 717 | |
| 2 | Frederick | 2 | |
| 3 | Gaithersburg | 2 | |
| 4 | Damascus | 1 | |
| 5 | Libertytown | 1 |
Some ZIPs span multiple counties. The primary above is the largest by population weight; secondary counties are below.
| County | State | Weight | |
|---|---|---|---|
| Frederick County | MD | 1.00 | FIPS 24021 |
| Howard County | MD | 1.00 | FIPS 24027 |
| Montgomery County | MD | 1.00 | FIPS 24031 |
The figures above are historical. For today's air quality, fire-weather warnings, and active fires, go to the official sources.
NFIRS reports each fire incident with a 5-digit address ZIP. We aggregate those rows directly to produce ZIP-level totals — 1,108 incidents in this ZIP across 2021–2025. Building-fire breakdowns (Area of Origin, Heat Source, ignition cause) only count fires investigators classified beyond the basic incident report. Because NFIRS reporting is voluntary, totals are a strong indicator rather than a complete census.