ZIP 01850 recorded 144 fire and hazmat incidents in 2025, 791 across 2021–2025. Primary county: Middlesex County, MA. FEMA NRI rates wildfire risk here as High.
791 incidents from 2021 through 2025 inside this ZIP.
| Year | Incidents | |
|---|---|---|
| 2021 | 142 | |
| 2022 | 173 | |
| 2023 | 170 | |
| 2024 | 162 | |
| 2025 | 144 |
Oct peaks. Jul dips. Aggregated across all 5 years inside this ZIP.
Top 5 NFIRS incident types for ZIP 01850 across 2021–2025.
| # | Incident type | Count | Share | |
|---|---|---|---|---|
| 1 | Unauthorized burning | 133 | 16.8% | |
| 2 | Cooking fire, confined to container | 130 | 16.4% | |
| 3 | Gas leak (natural gas or LPG) | 94 | 11.9% | |
| 4 | Electrical wiring/equipment problem, other | 79 | 10.0% | |
| 5 | Carbon monoxide incident | 68 | 8.6% |
For the 7 building fires reported here in 2025, here's how investigators classified ignition cause.
NFIRS Area of Origin for ZIP 01850 fires across 2021–2025.
| # | Area of origin | Count | Share | |
|---|---|---|---|---|
| 1 | Cooking area, kitchen | 18 | 20.2% | |
| 2 | Bedroom - < 5 persons; included are jail or prison | 11 | 12.4% | |
| 3 | Outside area, other | 7 | 7.9% | |
| 4 | Engine area, running gear, wheel area | 6 | 6.7% | |
| 5 | Common room, den, family room, living room, lounge | 5 | 5.6% | |
| 6 | Highway, parking lot, street: on or near | 5 | 5.6% | |
| 7 | Wall surface: exterior | 4 | 4.5% | |
| 8 | Exterior stairway, ramp, or fire escape | 3 | 3.4% | |
| 9 | All other areas | 30 | 33.7% |
NFIRS HEAT_SOURC code — the physical thing that started the fire.
| # | Heat source | Count | Share | |
|---|---|---|---|---|
| 1 | Undetermined | 20 | 22.5% | |
| 2 | Heat from powered equipment, other | 13 | 14.6% | |
| 3 | Cigarette | 13 | 14.6% | |
| 4 | Arcing | 7 | 7.9% | |
| 5 | Radiated, conducted heat from operating equipment | 5 | 5.6% | |
| 6 | Hot or smoldering object, other | 4 | 4.5% | |
| 7 | Heat from other open flame or smoking materials | 4 | 4.5% | |
| 8 | Heat from direct flame, convection currents | 4 | 4.5% | |
| 9 | All other sources | 19 | 21.3% |
Largest single-incident losses in ZIP 01850 across 2021–2025. These 8 fires alone account for 13475% of the ZIP's 2025 reported total.
| # | Property loss | Type | Year | Severity |
|---|---|---|---|---|
| 1 | $750,000 | Building fires | 2024 | Major |
| 2 | $260,000 | Building fires | 2021 | Major |
| 3 | $150,000 | Building fires | 2021 | Significant |
| 4 | $100,000 | Building fires | 2022 | Significant |
| 5 | $100,000 | Building fires | 2024 | Significant |
| 6 | $80,000 | Building fires | 2021 | Significant |
| 7 | $75,000 | Building fires | 2021 | Significant |
| 8 | $75,000 | Building fires | 2022 | Significant |
Some ZIPs span multiple cities. Ranked by 5-yr NFIRS incidents inside ZIP 01850.
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 — 791 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.