Standing analysis, dated and sourced
This desk publishes durable explanations rather than reported events. Each piece covers a mechanism that does not expire — how the action level was set, how radon-resistant construction provisions reach an actual house, what changes when a state restructures its licensing — and each names the specific developments that would require it to be revised.
We do not publish unverified announcements. Everything here carries a publication date, a review date, an update date derived from its own revision log, and the sources it rests on. Our editorial policy explains why that distinction matters to us.
Most recently updated
- — Where EPA’s 4 pCi/L Radon Action Level Comes From
- — If EPA Radon Guidance Changed, What Would Actually Change for You?
- — How Radon-Resistant Construction Requirements Reach an Actual House
- — Passive Radon Systems in New Builds: What to Verify Before Closing
- — Who Licenses Radon Work in the Ten States We Serve
Federal guidance
How EPA frames radon risk and action levels, where those numbers come from, and what a change to them would mean for a homeowner decision.
- Where 4 pCi/L comes from — A feasibility threshold that gets read as a safety line — and what the difference means for your decision.
- If federal guidance changed — Which parts of a homeowner decision are anchored to the federal number, and which would not move at all.
Building codes
How radon-resistant construction provisions travel from model code into state and local practice, and why a new house still needs a test.
- How RRNC reaches a house — Four steps between a provision existing and your house having one — and why none of them replaces a test.
- Passive systems in new builds — What to ask a builder, what to look for yourself, and why the timing of the test matters to your warranty.
State licensing
How the ten states we serve credential radon professionals, what changes when a regime does, and how to verify a credential yourself.
- Who licenses radon work — State licence, state certification, or national credential — and what each means when you check a contractor.
- Licensing change mid-project — Open quote, scheduled install, or pending verification — how a regime change lands on each.
Measurement and mitigation technology
What has actually changed in fans, monitors, and diagnostics — and what has not, despite the marketing.
- Continuous monitors — The hourly log is the product. What it proves, and which decisions it still cannot carry.
- Fan technology — Real improvements in selection, monitoring, and efficiency — against a design principle that has not moved.
Housing market
How radon behaves as a line item in a transaction, and what shifts in inventory, rates, and inspection practice do to that line.
- Radon and market conditions — The measurement is the same in any market. Who pays for it is not.
- Inspection practice — A separate service, a separate credential, and a separate deadline — three facts that catch buyers out.
Research
How radon studies are constructed, what makes one load-bearing, and how to read a headline about one without being misled.
- Reading a radon study — Design, exposure assessment, confounding, and aggregation — the four places a radon headline goes wrong.
Related resources
- State resource centres — the agency, licensing regime, and disclosure practice for each of the ten states we serve.
- Homeowner guides — the decision content behind these dispatches.
- Research methodology — how this content is built and what we deliberately do not attempt.
Get quotes from credentialed local contractors
Free to request and no obligation. We verify credentials with the issuing authority before any request routes to a contractor.