§ 4.1 — Chevy Chase, MD

Certified radon mitigation in Chevy Chase, MD

1 current listing from the official file. Verify the credential number before you hire.

Last verified August 29, 2026. Methodology NRPP. NRSB.

Certified radon testingCertified radon mitigation

  1. John S. Swett

    Radon Abatement Services

    current NRSB RRS-1G0006

    mitigation

    August 29, 2026cite ↗
Fig. 4Chevy Chase, MD, approximate. Pin is the city on the official file, not a street address.

Appendix A — Before you hire

  1. Who holds the credential, and can they show the same number that appears on this page?
  2. What test method or mitigation system will they use for this building?
  3. How will they document results or the finished system?

§ 4.3

Nearby places in Maryland

Maryland pages here use current NRPP or NRSB certifications. City pages use the city printed on that record, not a ZIP-radius search. A national certification is not a Maryland license. Some states require a separate state credential to work legally. Read the methodology. Credential status can change.