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

§ 4.1 — Cleveland, OH

Certified radon mitigation in Cleveland, OH

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 A Verdi

    Guardian Airworks Llc

    current NRPP № 115149

    mitigation, testing

    (440) 477-7658August 29, 2026cite ↗
Fig. 4 — Cleveland, 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.