Radon Mitigation Contractors

Radon mitigation contractors install systems that pull radon gas out from under homes and vent it safely outside. The job takes them into basements and crawl spaces, through concrete slabs and up onto roofs, with the hazards of dust, wiring and confined spaces along the way.

• Residential
• Construction
• Home Services

What the system does

Radon is a radioactive gas that seeps up from soil into buildings. It’s the second leading cause of lung cancer in the U.S. The EPA recommends fixing a home when radon is 4 picocuries per liter (pCi/L) or higher and considering it between 2 and 4.

The most common fix is sub-slab depressurization: a pipe goes through the slab into the gravel below, and a fan draws the gas up and out through a vent stack above the roof, so it disperses outside. Other methods include sealing, crawl space barriers and vents.

Drilling and coring through concrete

• Use wet methods or a vacuum shroud when coring or drilling the slab. Concrete dust contains crystalline silica. See Silica and Core Drills.
• Wear a respirator (N95 or better, per your exposure assessment), eye protection and hearing protection.
• Check for utilities and rebar before coring. Use a scanner. Hitting a pipe or live wire is a real risk.
• Use GFCI protection on power tools and cords in damp basements. See GFCI.

Crawl spaces and tight spaces

• Crawl spaces are often wet, dusty, low and hot or cold. They can hold mold, droppings, insulation fibers, sharp objects and sometimes asbestos or lead hazards in older homes. Test or assume hazardous materials before disturbing them.
• Wear coveralls, gloves, knee pads, a respirator and a headlamp. Tell someone where you are.
• Watch for snakes, spiders and rodents. Don’t sweep or vacuum droppings dry. See Biological Hazards.
• Some crawl spaces are confined spaces if they have hazards or limited exit. See Confined Spaces.

Roof work

The vent stack has to exit above the roofline, so installers work at heights. Use fall protection, and ladders set up correctly. See Roof Work and Extension Ladders. Check for overhead power lines before raising pipes and ladders.

Electrical work

• The fan needs electrical power. Where the fan is wired, follow local code and the manufacturer’s instructions. In many places a licensed electrician or permit is required.
• Install a visible system gauge (manometer) so the homeowner can see the system is working, and an alarm if the fan stops, as local practice requires.
• Keep fans and wiring dry, and avoid running wiring through damp areas without proper protection. See Wet Locations.

Sealing and chemicals

Contractors seal cracks and openings with caulks and sealants. Some contain solvents or isocyanates, so ventilate and follow the safety data sheet. See Solvents and Safety Data Sheets.

Certification and testing

• Many states license or certify radon mitigation contractors. Recognized programs include those from the National Radon Proficiency Program (NRPP) and the National Radon Safety Board (NRSB). Check your state rules.
• Test the home after installation to confirm levels are down, and recommend retesting every 2 years or after major changes.
• Radon exposure for workers is usually low with mitigation work, but follow your employer’s safety program.

Before each job

• Utilities, rebar and wiring located before coring
• Wet or vacuum dust control and respirator ready
• Crawl space hazards checked; partner or check-in plan
• Ladder and fall protection ready for the roof
• GFCI on all cords; fan wiring done to code

Last updated: October 4, 2026