ZIP 21791 recorded 88 fire and hazmat incidents in 2025, 352 across 2021–2025. Primary county: Carroll County, MD.
352 incidents from 2021 through 2025 inside this ZIP.
| Year | Incidents | |
|---|---|---|
| 2021 | 61 | |
| 2022 | 63 | |
| 2023 | 66 | |
| 2024 | 74 | |
| 2025 | 88 |
Dec peaks. May dips. Aggregated across all 5 years inside this ZIP.
Top 5 NFIRS incident types for ZIP 21791 across 2021–2025.
| # | Incident type | Count | Share | |
|---|---|---|---|---|
| 1 | Building fires | 88 | 25.0% | |
| 2 | Power line down | 64 | 18.2% | |
| 3 | Authorized controlled burning | 25 | 7.1% | |
| 4 | Chimney or flue fire, confined to chimney or flue | 22 | 6.2% | |
| 5 | Gas leak (natural gas or LPG) | 13 | 3.7% |
For the 18 building fires reported here in 2025, here's how investigators classified ignition cause.
NFIRS Area of Origin for ZIP 21791 fires across 2021–2025.
| # | Area of origin | Count | Share | |
|---|---|---|---|---|
| 1 | Undetermined | 16 | 21.6% | |
| 2 | Open area - outside; included are farmland, field | 9 | 12.2% | |
| 3 | Outside area, other | 6 | 8.1% | |
| 4 | Other | 5 | 6.8% | |
| 5 | Engine area, running gear, wheel area | 5 | 6.8% | |
| 6 | Cooking area, kitchen | 4 | 5.4% | |
| 7 | Vehicle storage area; garage, carport | 4 | 5.4% | |
| 8 | Duct: hvac, cable, exhaust, heating, or AC | 4 | 5.4% | |
| 9 | All other areas | 21 | 28.4% |
NFIRS HEAT_SOURC code — the physical thing that started the fire.
| # | Heat source | Count | Share | |
|---|---|---|---|---|
| 1 | Undetermined | 30 | 40.5% | |
| 2 | Heat source: other | 11 | 14.9% | |
| 3 | Radiated, conducted heat from operating equipment | 7 | 9.5% | |
| 4 | Arcing | 6 | 8.1% | |
| 5 | Hot ember or ash | 5 | 6.8% | |
| 6 | Heat from powered equipment, other | 4 | 5.4% | |
| 7 | Spark, ember or flame from operating equipment | 3 | 4.1% | |
| 8 | Heat from other open flame or smoking materials | 2 | 2.7% | |
| 9 | All other sources | 6 | 8.1% |
Largest single-incident losses in ZIP 21791 across 2021–2025. These 8 fires alone account for 284% of the ZIP's 2025 reported total.
| # | Property loss | Type | Year | Severity |
|---|---|---|---|---|
| 1 | $250,000 | Building fires | 2025 | Major |
| 2 | $200,000 | Building fires | 2022 | Significant |
| 3 | $100,000 | Building fires | 2021 | Significant |
| 4 | $100,000 | Building fires | 2024 | Significant |
| 5 | $100,000 | Building fires | 2024 | Significant |
| 6 | $75,000 | Building fires | 2025 | Significant |
| 7 | $60,000 | Building fires | 2021 | Significant |
| 8 | $50,000 | Building fires | 2024 | Significant |
Some ZIPs span multiple cities. Ranked by 5-yr NFIRS incidents inside ZIP 21791.
| # | City | 5-yr incidents | |
|---|---|---|---|
| 1 | Union Bridge | 303 | |
| 2 | Frederick | 2 | |
| 3 | Libertytown | 2 | |
| 4 | New Market | 1 | |
| 5 | Woodsboro | 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 |
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 — 352 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.