Certified radon testers & mitigatorsOhio — testing — verified 29 Aug 2026

§ 4.1 — Columbus, OH

Certified radon testing in Columbus, OH

3 current listings 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 Johnson

    J & K Enterprises Ohio Llc

    current NRSB № RMS-24MS090

    testing

    August 29, 2026cite ↗

  2. Matt McClelland

    Ctl Engineering, Inc.

    current NRSB № RMS-25MS040

    testing

    August 29, 2026cite ↗

  3. Paul Knox

    Healthy Homes Radon Testing, Llc

    current NRPP № 115630

    testing

    (614) 400-6959August 29, 2026cite ↗
Fig. 4 — Columbus, OH, 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 Ohio

Ohio 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 Ohio license. Some states require a separate state credential to work legally. Read the methodology. Credential status can change.