Radon · ZIP 19958
Radon in Lewes (DE), DE
ZIP 19958 (Delaware) — radon summary sourced from EPA Radon Zones. Refreshed on the cadence of the primary regulator with every claim cited to the source record.
What lands here
Pages show the county zone, what the classification means for home testing recommendations, and state-level supplementary data where available.
Source & refresh
EPA Radon Zones. Refreshed static 1993 baseline plus state-level supplementary updates. Stale data is flagged, never silently served. Primary source →
Limitations specific to this source
Radon is a regional indicator. Address-level radon measurement requires an at-home test kit (often free from state health departments).
Delaware context
Sea-level rise, agricultural runoff
Delaware has the lowest mean elevation of any US state and FEMA NFHL coverage extends well inland in Sussex County. Agricultural runoff in poultry-heavy regions affects EPA SDWIS small-system nitrate readings. Lead-service-line inventories statewide are nearing 2024 LCRR baseline.
See Delaware state page for the full state-level rollup across all 12 dimensions.
Read more on radon
Editorial deep-dives explaining the source data, its limits, and how to read it.
EPA Radon Zones — what 1, 2, and 3 mean and when you should test
EPA classifies every US county into Zone 1 (high), Zone 2 (moderate), or Zone 3 (low) for radon. Plain-English guide to the classifications and at-home testing.
EPA SDWIS — how to read drinking-water violations and what they actually mean
Plain-English guide to EPA SDWIS drinking-water violations: health-based vs. monitoring vs. reporting violations, MCLs, and what triggers a public notice.
Radon and real estate — what disclosure laws and home tests actually require
What home sellers must disclose about radon by state, when home tests are required, and how to interpret radon-mitigation systems if a home you're buying has one.
Radon disclosure during real-estate transactions — state-by-state
Whether sellers must disclose known radon results varies by state. Quick map of mandatory-disclosure states + what to ask for during inspection.
Full dashboard for ZIP 19958
Radon is one of twelve dimensions zipradar federates per address. See the full federated summary for ZIP 19958:
Open Lewes (DE), DE dashboard →Frequently asked questions
What is the radon for ZIP 19958?
Radon for ZIP 19958 (Lewes (DE), Delaware) is federated from EPA Radon Zones. Pages show the county zone, what the classification means for home testing recommendations, and state-level supplementary data where available. Refreshed static 1993 baseline plus state-level supplementary updates — see /methodology for full source citations and refresh-cadence details.
Where does the radon data come from?
EPA Radon Zones (primary regulator). zipradar federates radon on the regulator's published cadence: static 1993 baseline plus state-level supplementary updates. Every claim cites the source record; stale data is flagged, never silently served. The primary source URL: https://www.epa.gov/radon/find-information-about-local-radon-zones-and-state-contact-information.
What are the limitations of radon data?
Radon is a regional indicator. Address-level radon measurement requires an at-home test kit (often free from state health departments).
Is ZIP 19958 (Lewes (DE)) data current?
Last verified 2026-06-10. Radon for ZIP 19958 refreshes static 1993 baseline plus state-level supplementary updates per EPA Radon Zones cadence. See the full ZIP dashboard at /zip/19958/ for all 12 dimensions side-by-side.