Minnesota radon directory study MDH search pulled: 2026-09-28 (Mon, 28 Sep 2026 18:16:07 GMT). Analysis: RadonTestingCompanies.com Article: https://radontestingcompanies.com/guides/minnesota-radon-directory-study Source: https://radon.web.health.state.mn.us/serviceProviders.jsf SCOPE Counts are professional license entries from MDH's public service-provider search. A license entry is one credential ID. It is not a company, a person counted once across license types, or proof that someone serves a county. A listed city is the address city on the record. It is not a service area. MDH also prints a service-area note such as statewide or a mileage radius. This study does not use that note as geography. A zero means no address in this pull was assigned there. It does not establish an absence of available service, a shortage, or a household radon risk. The live directory is a separate import and can show a different set. PULL Provider type Measurement and Mitigation. Service type Single Family Homes (SFH), Multi Family Buildings (MFB), and Schools and Large Buildings (SLB). ZIP left blank. Analysis Laboratory was not requested. Each search's collected rows equaled the row count MDH reported, and credential IDs were unique inside each search. Search row counts: Measurement SFH 341; Measurement MFB 138; Measurement SLB 99; Mitigation SFH 116; Mitigation MFB 62; Mitigation SLB 47. The single-family searches alone return 341 measurement IDs and 116 mitigation IDs. The published counts use all three service types. LICENSE TOTALS 399 credential IDs. 372 returned by at least one Measurement search. 120 returned by at least one Mitigation search. 93 are in both totals. 27 are in a Mitigation search and not a Measurement search. Each of those records also prints a measurement service. They are counted as mitigation licenses only. No Measurement-search ID that is absent from the Mitigation search prints a mitigation service. 341 list a Minnesota address (323 measurement, 99 mitigation, 81 in both). 58 list an address outside Minnesota and are excluded from city and county counts. Address state counts: MN 341, WI 21, ND 13, IL 12, IA 2, MO 2, MI 2, KY 2, SC 1, TX 1, FL 1, SD 1. COMPANY-NAME STRINGS 258 distinct company-name strings on all addresses, and 224 on Minnesota addresses, after trimming, collapsing whitespace, and ignoring case. 52 Minnesota strings appear on more than one license. Punctuation, LLC/Inc variants, and different names for the same firm are not merged. MDH's public search does not include a company license ID. These are not counts of businesses. CITY METHOD Denominator: 2025 Census Gazetteer of places, Minnesota, legal/statistical area code 25 (city) and functional status A (active). 856 places. Names are compared after lowercasing, removing punctuation, collapsing spaces, and expanding St. to Saint and Ft. to Fort. 1 normalized name matches more than one incorporated place and is held out: St. Anthony / St. Anthony. Classified cities: 854. Both services: 53. Measurement license and no mitigation license: 47. Mitigation license and no measurement license: 7. Neither: 747. Mitigation-only cities all print a measurement service on those licenses: true. Single-family-only city flag differences: Cleveland (tester_only vs neither); Eagan (both vs tester_only). COUNTY METHOD Denominator: 2025 Census Gazetteer of counties, 87 Minnesota counties. If the address city matches one incorporated place, the county comes from the 2025 county-subdivision gazetteer rows named "{city} city". The first five digits of that GEOID are the county. One county assigns the license. More than one county leaves it unassigned, and those counties are not treated as empty. If the address city matches no incorporated place, it is assigned only when the printed ZIP's 2020 ZCTA lies in exactly one Minnesota county. A ZCTA in more than one county leaves those counties unresolved. A USPS ZIP is not a ZCTA. This rule is not used to correct a city spelling. Addresses outside those rules: Cedar 55011 (assigned-by-zcta: Anoka); Eden Prarie 55344 (assigned-by-zcta: Hennepin); Esko 55733 (unresolved-zcta: Carlton, St. Louis); NYA 55397 (unresolved-zcta: Carver, McLeod); Outing 56662 (assigned-by-zcta: Cass); Webster 55088 (unresolved-zcta: Rice, Scott). Multi-county incorporated cities: Blaine (Anoka, Ramsey); Braham (Isanti, Kanabec); Chanhassen (Carver, Hennepin); Hastings (Dakota, Washington); Mankato (Blue Earth, Le Sueur, Nicollet); Northfield (Dakota, Rice); Rockford (Hennepin, Wright); Sartell (Benton, Stearns); St. Cloud (Benton, Sherburne, Stearns). County flags use assigned counts. A county with an assigned measurement license, no assigned mitigation license, and no unresolved mitigation address that could fall there is tester_only. A county with nothing assigned, and no unresolved address that could fall there, is neither. Any other mixed case is unresolved. Flags: both 25; tester_only 11; mitigator_only 0; neither 43; unresolved 8. COLUMN DEFINITIONS: county-comparison.csv county_fips: Five-character Census county identifier. Minnesota begins with 27. county: County name without the word County. testers: Measurement-search credential IDs assigned to this county. mitigators: Mitigation-search credential IDs assigned to this county. possible_testers: Measurement-search IDs not assigned to one county whose candidate counties include this one. Not added to testers. possible_mitigators: The same for Mitigation-search IDs. flag: both, tester_only, mitigator_only, neither, or unresolved. This is our analysis of published records. MDH has not reviewed or endorsed it.