How to Choose a Radon Mitigation Contractor in York, PA

Radon is the rare home-service trade where Pennsylvania actually regulates who can do the work. Use that. Then check the handful of things the state does not.

1. DEP certification, for the firm and the person

Required by law since 1988. Look the company up in the DEP Radon Services Directory (updated monthly) and ask which certified individual will be on site. Both the firm and the technician should hold current certification. Ask to see the DEP ID card. Our certified contractor list is a starting point, checked against the September 2026 lists.

2. A written bid that guarantees a number

DEP's guidance: the bid should guarantee the home below 4.0 pCi/L for the quoted price. Some firms guarantee lower (2.0 is achievable in most York basements). Get the guarantee term in writing. Local examples run from five to ten years.

3. The design follows DEP rules

• Fan in the attic, garage, or outside the living envelope. A fan in the basement is a code violation and a leak risk.
• Exhaust above the roof edge, away from windows.
• A manometer on the pipe so you can see suction at a glance.
• A label with the installer's name, phone, and DEP number.

4. A diagnostic, not a guess

Good installers do a communication test: drill a small test hole, apply suction at the planned pit, and measure whether the vacuum reaches the far corners of the slab. That tells them whether one suction point is enough. In York's older homes with additions on separate slabs, it often is not. A quote that skips this and prices "a standard system" may be underbidding.

5. Post-mitigation testing by someone independent

DEP says to retest no sooner than 24 hours after the fan goes on, then again in the opposite season. Some installers include a follow-up test; it is better to use a separate DEP-certified tester or DEP's free long-term kit so the installer is not grading their own work.

6. Warranty on the fan and the result

Fan manufacturer warranties are typically five years. Ask what the installer adds on top for labor and for the guaranteed level, and what happens if the first post-test comes back above the target.

7. Insurance and registration

Ask for a certificate of liability insurance. Any contractor doing $5,000 or more of home improvement work a year in PA must also be registered with the Attorney General (HIC number).

Questions to ask on the phone

1. What is your DEP firm number, and who on my job is individually certified?
2. What level do you guarantee, for how long, in writing?
3. Do you run a communication test before pricing suction points?
4. Where will the fan go, and where does it exhaust?
5. Who does the post-mitigation test?
6. What is the fan warranty and the labor warranty?
7. Will you seal the sump and the major cracks as part of the job?

Red flags

• Cannot produce a DEP number, or the number is not in the current directory.
• Fan mounted in the basement.
• No gauge, no label.
• A quote by phone with no site visit for a house older than 1970.
• "Radon-proofing" sealants or paints sold as a substitute for a system. Sealing alone does not reliably reduce radon.

Next: what it should cost · who is certified · back to the York radon guide.

Sources: PA DEP Radon Certification page and fact sheet 2940-FS-DEP4430; 25 Pa. Code Chapter 240; U.S. EPA Consumer's Guide to Radon Reduction. Last reviewed September 15, 2026.