§ 4.1 — Baltimore, MD
This page lists 13 people and firms with a current radon testing credential whose official record names Baltimore, MD. Each row shows the credential number, the issuing body, and its own verification date. The latest record check on this page was August 29, 2026; other records may have been checked earlier. Source: the official file linked on each listing. Verify the number before you hire.
Testing listings are people credentialed to measure radon. Mitigation listings are people credentialed to install a reduction system. Some people appear on both pages when the official file says they hold both.
current NRPP № 114279
current NRSB № RMS-12SS024
current NRPP № 111321
current NRPP № 110325
current NRSB № RMS-21SS005
current NRPP № 109871
current NRPP № 110771
current NRPP № 110774
current NRPP № 109162
current NRPP № 115206
current NRPP № 115710
current NRPP № 110838
current NRPP № 112288
Appendix A
Open the source link on this page and match the name and credential number to the official file. Status can change after a record’s verification date. The latest record check on this page was August 29, 2026; check each record’s date. If the official page disagrees with this directory, trust the official page. We do not invent credential numbers.
The U.S. EPA does not certify radon contractors. EPA publishes guidance on finding a qualified radon service provider and points to state programs and national certifications. This directory is not affiliated with EPA. We do not display EPA-certified badges.
Last verified on an individual record is the date we checked its official source. The latest credential check on this page was August 29, 2026; other records may have earlier dates. We refresh the roster monthly. Current means the person appeared as currently credentialed on the source at that record’s verification date. Credentials can expire between refreshes, so follow the source link.
Appendix A.2
The full checklist: Certified radon tester: what they do and how to hire one
§ 4.3
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 state license in Maryland. Some states require a separate state credential to work legally. Read the methodology. Credential status can change.