Question 1

How much does radon mitigation cost in Columbus?

Accepted Answer

Most Central Ohio basement and slab homes land between $1,200 and $2,400 for an active sub-slab system. Crawl spaces that need a sealed membrane run $1,800 to $3,500. A professional short-term test is $150 to $300. The spread inside those ranges comes from the house, not the ZIP code. A 1990s Dublin or Pickerington slab with a clear path to the attic sits near the bottom. A Clintonville or Bexley basement with a patched floor, a sump, and walls that need extra sealing sits near the top, and a house that needs a second suction point can reach it. Ohio's mitigation standards also require items that belong in every price: a monitor or marked gauge, labels, an exterior fan hard-wired with its own outdoor disconnect, and a sealed sump cover that can still be lifted for pump service. Every Ohio proposal has to show the installation price and an estimate of what the system costs to run each year, so two quotes can be compared line for line. Our pricing guide by foundation type breaks the tiers down, and the calculator gives a starting range.

Question 2

How long does radon mitigation take?

Accepted Answer

A single-suction-point system in a basement or slab home is usually a one-day install. Crawl spaces that need a membrane, and houses with two foundation types, can take longer. The follow-up test then runs at least 48 hours. The install day is only the middle of the sequence. Before it, Ohio's mitigation standards call for a visual inspection, a floor plan sketch, and a communication test wherever the material under the slab is unknown, so the suction point is chosen from data rather than habit. After it, the post-mitigation test has to begin no sooner than 24 hours and no later than 30 days after the fan is switched on, run by the specialist who installed the system or by an independent Ohio-licensed tester. Weather can nudge the calendar too: Ohio's testing rules bar short tests during severe storms or sustained winds of 30 mph or more, which can push a retest by a day or two in a blustery March. If a closing date is driving the schedule, say so on the first call and the plan gets built backward from it.

Question 3

Is radon really a problem in Columbus?

Accepted Answer

Yes. Every Central Ohio county sits in EPA Radon Zone 1, and Franklin County's 16,142 pre-mitigation tests from 2008 to 2017 had an estimated mean of 9.5 pCi/L, more than twice the EPA action level of 4.0. The county figure comes from an American Lung Association analysis of CDC tracking data, and it agrees with much older state work: the 1988-89 EPA and Ohio residential survey found 64 percent of 170 Franklin County homes above 4 pCi/L on short screening tests. The cause is geology. The Ohio Shale, the largest uranium source in the state, runs in a north-south band under Franklin and Delaware counties, and glaciers smeared shale and limestone debris across the region. The health stakes come from the EPA: about 21,000 US lung cancer deaths a year are tied to radon, roughly 2,900 of them among people who never smoked. None of that predicts a single house. Averages describe the region, and only a test tells you what your own basement is doing. See why Ohio radon runs high.

Question 4

How does radon get into a Columbus house?

Accepted Answer

Radon travels in the soil gas under your foundation. A heated house sits at slightly lower pressure than the ground, so it draws that gas in through the floor-wall joint, cracks, sumps, drains, pipe openings, crawl-space dirt, and joints in block or stone walls. Central Ohio adds two local twists. First, most of the region is covered in glacial deposits, and the USGS found that the permeability of those deposits is the strongest control on how much radon reaches the surface: dense clay till slows it, while sand and gravel outwash along valleys like the Scioto and Olentangy lets it move freely. Second, the housing stock offers plenty of doors. A 1920s Clintonville basement may have mortared stone walls and a floor poured in sections, a postwar Whitehall ranch may sit over an open crawl, and a newer Hilliard split-level often has a slab and a crawl under one roof. Ohio's mitigation standards require the floor-wall joint, cracks, and utility openings to be sealed during an install, but sealing supports the fan; it never replaces it. See how a sump pit fits in.

Question 5

How often should I test my home for radon?

Accepted Answer

The Ohio Department of Health recommends retesting a single-family home every two years and after any significant renovation. Test sooner if you start using a lower level, replace the radon fan, or change the sump, waterproofing, or HVAC. ODH sets a longer clock for bigger buildings: multifamily, school, and commercial buildings should be retested every five years or after significant renovation. In a house with a mitigation system, the first test after the install belongs inside Ohio's window of 24 hours to 30 days after the fan starts, and the installer is required to advise you in writing to retest at least every two years after that. Between tests, the gauge on the pipe is the everyday check. A two-year rhythm fits the climate zone 5A heating season well: pick a month between November and March, close the house the way the testing protocol asks, and keep each result with the install paperwork so you can compare year over year. The retest schedule lays out the full timeline.

Question 6

Short-term or long-term radon test: which one do I need?

Accepted Answer

A short-term test, 48 hours to 90 days under Ohio's protocol, is the tool for a home sale and a first screening. A long-term test of more than 90 days shows the year-round average and is the better basis for a borderline decision. Ohio's recommended strategy for a home that is not being sold starts with a short-term test in the lowest livable level, then adds a second short-term test or a long-term test when the first result lands between 4 and 8 pCi/L. For a sale, only the short route is practical, and Ohio requires at least 48 hours using either two side-by-side devices or a continuous monitor. Long-term devices, such as alpha-track detectors, suit a homeowner who wants the whole seasonal swing of a zone 5A year, and they need far less babysitting than a closed-house short test. Neither type is more official than the other; they answer different questions. The comparison page lays them side by side.

Question 7

What warranty comes with a radon system?

Accepted Answer

Two separate things: a written workmanship warranty on the install, and the fan maker's warranty. Ohio also requires every proposal to state either a guarantee to bring the average below 4 pCi/L, with its conditions, or why no guarantee is offered. The guarantee statement is the piece most homeowners never see spelled out elsewhere, and it comes from the Ohio Radon Mitigation Standards in the appendix to OAC 3701-69-08. Read its conditions; most are reasonable, such as keeping the fan running and the sump cover sealed. On the fan, the EPA notes that fans often last five years or more and that manufacturer warranties tend not to exceed five years, so expect at least one fan replacement over the life of the house. Ask whether the workmanship warranty transfers to a buyer if a sale is possible. Keep the closeout package, which Ohio requires to include the contract and warranties, the floor plan drawing, and the pre- and post-mitigation results. If the post-mitigation test misses the guaranteed level, the correction belongs under that guarantee. See what an Ohio proposal must include.

Question 8

Will a radon system raise my utility bills?

Accepted Answer

A little. The fan runs around the clock on electricity, and the system can draw a small amount of heated or cooled air. Ohio requires every mitigation proposal to include an estimate of the annual operating cost, so you see the number before signing. The EPA's guidance is plain: fan-powered systems are the most effective option and slightly increase the electric bill, by an amount that depends on the climate, the system, and the house. In a zone 5A Central Ohio winter the bigger variable is heat loss, and the sealing done during the install (floor-wall joint, cracks, the sump cover) limits how much warm basement air the fan can pull down through the slab. You can check the fan's draw yourself from the rating on its housing and your AEP Ohio rate. Never switch the fan off to save money; the EPA is explicit that it must run continuously for the system to work. If the operating estimate on a proposal looks high or oddly low, ask how it was calculated and which fan it assumes.

Question 9

Will I hear the radon fan inside the house?

Accepted Answer

Usually very little. Ohio's standards keep the fan out of the living space, in an attic, a garage that is not under a room, or outside, mounted to limit vibration. Most sound people notice is air at the discharge or a fan that is wearing out. Several of Ohio's mitigation rules are quietly noise rules: the main pipe must be at least 3 inches in diameter to avoid flow noise, the finished system must run at a reasonable noise level, fans sit in vertical runs, and they attach with removable couplings that help keep vibration out of the framing. On a Columbus house the real choice is usually between a fan on an exterior wall, which is simple but can put the pipe within earshot of a bedroom window, and an interior chase up to the attic. Walk the proposed route before the install and point out which rooms sit next to it. A fan that was quiet for years and has started to hum is a different problem, covered in why a radon fan gets noisy.

Question 10

Does every Columbus home need a radon system?

Accepted Answer

No. Only a home that tests high needs one: the EPA recommends fixing at 4 pCi/L or above and considering it between 2 and 4. But every home should be tested, because two houses on the same Central Ohio street can read very differently. The Ohio Department of Health recommends testing every occupied building that touches the ground, and the EPA says its zone map should not be used to decide whether a particular house needs a test. For a home that is not being sold, Ohio's recommended sequence starts with one short-term test in the lowest livable level. Under 4 pCi/L, no action beyond a retest in two years or after renovations. Between 4 and 8, a second short-term test or a long-term test sharpens the picture. At 8 or higher, a second short-term test, then a decision on the average. Some households choose to fix results between 2 and 4, especially when someone smokes or sleeps on the lowest level. See what your number means.

Question 11

We close in two weeks and the radon test failed. Is there time?

Accepted Answer

Usually, if the scope is settled quickly. A typical system is a one-day install, and Ohio lets the post-mitigation test start 24 hours after the fan runs, with a 48-hour minimum for a sale. The tight parts are the scoping visit and the signed paperwork. Work backward from the closing date. The post-mitigation result has to come from the specialist who installed the system or from an independent Ohio-licensed tester, and a sale test must run at least 48 hours with either two side-by-side devices or a continuous monitor recording 48 straight hours. Before any of that, Ohio requires a visual inspection and floor plan ahead of the written proposal, and a signed proposal before any work begins. That is why the first call matters more than anything else. Share the contract deadlines, the foundation type, and whether the house has a sump or crawl space, and the scope can be built around the calendar. The real estate radon service page covers how buyers and sellers usually split the work.

Question 12

Can I install a radon mitigation system myself in Ohio?

Accepted Answer

Legally, yes, on a home you own or lease: Ohio's licensing law exempts owners working on their own building. Anyone you pay must hold an ODH mitigation contractor license. The hard parts are diagnostics, sealing, fan placement, and the discharge rules. The owner exemption sits in ORC 3723.02 and covers testing and mitigating your own property. It does not make a homemade system match the Ohio Radon Mitigation Standards, which a buyer's inspector may hold it against later. Those standards keep the fan in an attic, a garage not under living space, or outside, never in a basement; put the discharge above the highest eave and at least 10 feet from nearby windows, doors, and a neighbor's openings; require a fan whose maker lists radon use; and call for a backdraft check wherever natural-draft gas appliances share the basement. If you go it alone, get a proper post-mitigation test and keep notes and photos, because the next owner will ask. Most people who price the parts, the roof work, and the diagnostics decide an installed system is the better trade.

Question 13

Can my sump pit be part of a radon system?

Accepted Answer

Yes, with care. Ohio's standards say a sump pit holding a working pump should not be the primary suction point. The pit does need an airtight, clear, serviceable cover, and it can be tied in as a secondary suction point. Central Ohio basements, especially damp ones near Big Walnut Creek, Alum Creek, or the Olentangy, often have sumps fed by drain tile, which links the pit to the soil under the whole floor. That makes an open pit one of the largest entry points in the house. Ohio's cover rules are specific: rot-proof rigid material or clear polycarbonate, a view port for watching the pump, strength to hold a 155-pound person, silicone rather than permanent caulk so the lid can come off for service, and a warning label naming who to call before removing it. If the sump is the basement's only relief for water, an alternative drain has to be provided, such as a trapped floor drain or a trapped drain set into the cover. See how radon gets in.

Question 14

Should I test for radon before buying a Columbus home?

Accepted Answer

Yes. Put a radon test inside the inspection period. In Ohio, anyone paid to test must hold an ODH radon tester or mitigation specialist license, and a sale test must run at least 48 hours with side-by-side devices or a continuous monitor. Start with the seller's disclosure. The Ohio Residential Property Disclosure Form asks, in its hazardous materials section, whether the seller knows of previous or current radon gas, with the level and any mitigation. An answer of "unknown" usually means nobody has tested. A pipe with a gauge on it means a system exists, so ask for its closeout package and the most recent result. During the test, the seller or occupant signs a noninterference agreement and a notice goes up at each entry, which is what lets the number stand if anyone questions it. If the result comes back at 4.0 or higher, Ohio's testing strategy for sales says fix the home, and the conversation turns to who pays. See radon in a Columbus home sale.

Question 15

Should I retest for radon after foundation or basement work?

Accepted Answer

Yes. Waterproofing, a new or replaced sump, slab cuts for plumbing, a basement finish, or crawl-space work can change how soil gas gets in. The Ohio Department of Health recommends retesting after significant renovation, whether or not a system is installed. Wait until the work is done and the house is back to normal operation, then test under closed-house conditions like any other test. If a mitigation system is already in place, leave it running; Ohio requires the tester to record on the report whether a system was present and operating. Three Central Ohio projects deserve special attention: interior drain tile and a new sump added to a wet Gahanna or Worthington basement, which changes what the sump cover has to do; a bathroom roughed into an older basement slab; and an addition built over a crawl on a postwar ranch. Note Ohio's rule on changes to the system itself: altering a mitigation system means bringing it up to the current Ohio standard, while simply swapping a worn fan does not. See finishing a basement the radon-smart way.

Question 16

What is radon?

Accepted Answer

Radon is a radioactive gas released as uranium in rock and soil breaks down. It has no color, smell, or taste. Indoors it collects on lower levels, and long exposure raises lung cancer risk. The only way to know your level is to test. In Central Ohio the uranium comes mostly from the Devonian Ohio Shale, which the USGS describes as averaging about 30 parts per million uranium and as the largest uranium source in the state, and from soils weathered out of the Columbus and Delaware limestones. Radon moves through soil as a gas and follows the easiest path, including up through a foundation. Its short-lived decay products do the damage: breathed in, they lodge in lung tissue. The EPA estimates about 21,000 radon-related lung cancer deaths in the United States each year. For scale, outdoor air averages about 0.4 pCi/L and indoor air about 1.3 pCi/L nationally, and the EPA recommends fixing a home at 4 pCi/L or more. See why Central Ohio runs high.

Question 17

Why is radon so high in Central Ohio?

Accepted Answer

Geology. The uranium-rich Ohio Shale runs north to south beneath Franklin and Delaware counties, and glaciers spread shale and limestone debris across the region. Every Central Ohio county sits in EPA Radon Zone 1. The USGS radon assessment for Ohio traces the pattern: counties averaging above 4 pCi/L tend to follow the Ohio Shale outcrop belt as glaciers redistributed it, along with soils formed from limestone. One finding surprises people. A study the USGS cites measured higher basement radon over the Columbus and Delaware limestones than over the shale nearby, likely because weathering concentrates uranium in iron-rich soil. Soil texture matters as well: sandy outwash and river alluvium let gas travel more easily than dense clay till or moraine ridges. The Olentangy Shale lies just beneath the Ohio Shale. For county numbers and the older state survey, see our Central Ohio radon zones table and the Ohio Shale explainer.

Question 18

What does pCi/L mean on a radon result?

Accepted Answer

Picocuries per liter of air, the US unit for radon concentration. The EPA action level of 4 pCi/L equals 150 becquerels per cubic meter (Bq/m3), the unit most other countries use. A picocurie is a trillionth of a curie, a unit of radioactive decay, so the number describes how much decay is happening in each liter of indoor air. For scale, the EPA puts average outdoor air near 0.4 pCi/L (15 Bq/m3) and the average US home near 1.3 pCi/L (50 Bq/m3), with its "consider fixing" band at 2 to 4 pCi/L (75 to 150 Bq/m3). Ohio test reports give results in pCi/L. To turn a European or WHO figure in Bq/m3 into pCi/L, divide by 37. When a report lists two side-by-side devices, Ohio requires both results and their average to be reported, and the average is the number to act on.

Question 19

Can I see or smell radon?

Accepted Answer

No. Radon has no color, odor, or taste, and it does not trip smoke or carbon monoxide alarms. Because nothing warns you, the EPA and the Ohio Department of Health both say a test is the only way to know. That is also why there is no list of symptoms to watch for; radon's harm shows up, if it does, as lung cancer after long exposure. Testing is cheap in Ohio. Homeowners can order a free kit through ohio.radon.com, a program the Ohio Department of Health links to and the Delaware Public Health District recommends, or buy a charcoal kit for $15 to $30. Follow Ohio's placement rules even for a do-it-yourself test: the lowest regularly used level, 20 inches to 6 feet off the floor, clear of exterior walls, doors, windows, heat sources, and the sump, and never in a kitchen, bathroom, or laundry room. The free Ohio test kit guide walks through each step.

Question 20

Are children at greater risk from radon?

Accepted Answer

The EPA says children have been reported to face greater risk than adults from some radiation-related cancers, but there are no conclusive data showing greater risk from radon. Because risk builds over years, a child's long future in the house is the practical reason to act. The honest version matters here. Radon risk is driven by concentration and time, and children who grow up in a house spend many years in it. A basement playroom, a teenager's lower-level bedroom, or a finished rec room in a Westerville or Gahanna split-level puts young people where readings are usually highest. The EPA also advises retesting on a lower level whenever a household starts using it regularly. Schools are a separate track; the Ohio Department of Health publishes a radon-in-schools FAQ, and parents can ask a district about its testing. At home the steps are the same for every family: test the lowest level that is lived in, fix results of 4 pCi/L or more, and consider fixing between 2 and 4. See finishing a basement safely.

Question 21

Do landlords in Ohio have to test for radon?

Accepted Answer

No. Ohio's radon law, ORC Chapter 3723, licenses testers and mitigators but does not require landlords to test rentals. Local health districts such as Delaware's note they have no statewide authority over indoor air in homes. Tenants can test their own unit with a kit. For an owner, the practical case for testing is simple: ground-contact units carry the exposure, results are cheap to get, and a high number is better found by the owner than by a tenant. ODH recommends retesting multifamily buildings every five years and houses every two. Mitigating a rental works like any home, done by an Ohio-licensed mitigation contractor, with the closeout package kept for the next tenant or buyer. A tenant who finds a high result should send the report to the owner in writing; free kits are available through ohio.radon.com. For obligations under a specific lease or a local housing code, ask a lawyer rather than relying on general guidance. See radon in apartments and condos.

Question 22

Can apartments and condos in Columbus have radon?

Accepted Answer

Yes, mainly units in contact with the ground: garden-level and first-floor units and those over a crawl space or basement. Upper floors usually read lower. The Ohio Department of Health recommends retesting multifamily buildings every five years. Central Ohio has plenty of ground-contact rental stock: garden units in older buildings near Ohio State, walk-ups in the Short North and Italian Village, and slab-on-grade townhomes across the suburbs. Ohio's measurement protocol treats multifamily buildings separately from houses, and testers must file their own procedures for them with ODH, while a single condominium unit is measured like a home. Large buildings are mitigated under a different national standard, ANSI/AARST SGM-MFLB-2023, rather than the single-family one. A tenant can test a unit with a kit, but mitigation involves the building, so it belongs to the owner or the association. See landlords and radon and our commercial and multifamily service.

Question 23

Should a brand-new home be tested for radon?

Accepted Answer

Yes. The EPA says every new home should be tested as soon as possible after move-in, even one built with radon-resistant features. If it reads 4 pCi/L or more, a fan can usually be added to the builder's passive pipe. New subdivisions around Powell, Lewis Center, Marysville, Plain City, and the Intel growth area near Johnstown often include some radon-resistant features: gravel under the slab, plastic sheeting over it, sealed openings, and a 3- or 4-inch vent pipe from under the slab to the roof, sometimes with an attic junction box for a future fan. Ohio's radon licensing law exempts that builder work during construction, so the builder is not doing licensed radon work and may never test the finished house. A passive pipe on its own also does less than a fan: the EPA puts passive sub-slab suction at 30 to 70 percent reduction and active suction at 50 to 99. Adding a fan later counts as mitigation under Ohio rules. See what a pipe with no fan means.

Question 24

How is radon mitigated in a crawl space or slab home?

Accepted Answer

Crawl spaces get sub-membrane depressurization: a sealed plastic membrane over the dirt with a fan drawing from beneath it. Slab and basement homes get sub-slab suction through a hole cored in the floor. Plenty of Central Ohio houses need both. Ohio's standards set the crawl-space minimums: a membrane of at least 6 mil polyethylene or 3 mil cross-laminated, heavier where the crawl holds storage or gets regular foot traffic; seams overlapped at least 12 inches and sealed; edges fastened mechanically to walls and piers; and access doors gasketed but never sealed shut. Depressurizing a crawl without a membrane is allowed only when the space is inaccessible. The EPA rates sub-membrane suction at 50 to 99 percent reduction, against 0 to 50 for simply venting the crawl. In split-levels and ranches with additions, common in Hilliard, Whitehall, and Reynoldsburg, one fan can often serve both areas when the layout allows. Crawl systems sit in the $1,800 to $3,500 tier. See crawl space radon mitigation.

Question 25

Can a heat recovery ventilator lower radon?

Accepted Answer

Somewhat, by diluting indoor air with outdoor air, but the EPA calls HRVs a limited-use option whose effect depends on the radon level and how much air they move. They work best in small spaces like basements and rarely replace sub-slab suction. HRVs come up in Central Ohio after a house has been tightened with foam insulation or new windows and the owner wants fresh air anyway. If one is part of a radon plan, Ohio's mitigation standards set rules for it: interior supply and exhaust ports at least 12 feet apart, exterior ports at least 10 feet apart and clear of snow and leaves, balanced airflow so the house is not depressurized, screened vents, and written instructions on filter and grille cleaning. The EPA suggests changing HRV filters twice a year. Any change to an existing HVAC system aimed at radon should be reviewed by the system's designer or a licensed mechanical contractor. For most houses, active sub-slab depressurization remains the primary fix.

Question 26

What is the cheapest way to reduce radon?

Accepted Answer

Sealing cracks and opening windows cost little but rarely get a house under 4 pCi/L; the EPA treats sealing as support for other methods, not a fix on its own. A fan-driven sub-slab system is the cost-effective route to a lasting result. The EPA's reduction table makes the point: active sub-slab suction cuts radon by 50 to 99 percent, passive suction without a fan by 30 to 70, and natural crawl-space ventilation by 0 to 50, while sealing is normally used only alongside another technique. Opening windows works only while they stay open, which is no plan for a zone 5A winter. The cheapest real fixes are in houses already set up for one: a builder's passive pipe that only needs a fan, $700 to $1,200 on the site's price list, or a slab home with an easy route to the attic. Most other homes start in the $1,200 to $2,400 range. Our pricing guide shows every tier.

Question 27

What must an Ohio radon mitigation proposal include?

Accepted Answer

Under Ohio's mitigation standards, a signed proposal comes before any work. It lists the Ohio license numbers, scope and completion date, chemical hazards, a compliance statement, homeowner maintenance, the price and yearly operating cost, and a guarantee statement. The requirements live in the appendix to OAC 3701-69-08, the Ohio Radon Mitigation Standards. The guarantee line has two legitimate forms: a guarantee that the system will bring the average below 4 pCi/L, with its conditions, or a statement that there is no guarantee and why. An old stone foundation can honestly earn the second answer; a plain slab rarely should. If the company that tested the house is also proposing the fix, Ohio requires the contract to say so plainly and to state the advantages of long-term testing and the value of a second opinion. When the job is done you should receive the floor plan drawing, test data, warranties, operating instructions, steps to take if the alarm trips, the installer's license number, and the ODH radon program's phone number. See what a quote should contain, line by line.

Question 28

Does homeowners insurance pay for radon mitigation?

Accepted Answer

Generally no. Homeowners policies are written for sudden, accidental damage, and radon is a long-standing condition of the soil. Most Central Ohio owners pay for testing and mitigation directly or negotiate it as part of a home sale. Read your own policy, but do not count on a claim. The more useful money questions are timing and who pays. In a sale, radon is a negotiated repair item: the Ohio disclosure form only asks what the seller knows, and no rule assigns the cost to either side. Outside a sale, compare written proposals, which in Ohio must show both the installation price and the estimated annual operating cost, and ask about any discount you qualify for. For tax or health-account questions, ask a tax professional rather than trusting general claims online. See who pays in a sale and our pricing guide.

Question 29

Can I test my own home for radon?

Accepted Answer

Yes. Ohio's licensing law exempts owners testing their own home, and Ohio homeowners can order a free kit through ohio.radon.com or buy one for $15 to $30. For a home sale, use an Ohio-licensed radon tester instead. A kit gives a sound screening number when it is used the way Ohio's measurement protocol describes. Close the house for at least 12 hours before starting and keep it closed during the test, apart from normal coming and going. Set the device in the lowest level that is lived in, 20 inches to 6 feet off the floor, at least a foot from exterior walls, 3 feet from doors, windows, and vents, 4 feet from heat sources, and 10 feet from the sump, and never in a kitchen, bathroom, laundry room, or closet. Skip stormy or very windy stretches. Mail it as soon as the kit instructions say. A sale test is a different animal: 48 hours minimum, side-by-side devices or a continuous monitor, a signed noninterference agreement, and a licensed tester. See the testing service.

Question 30

When is the best time of year to test for radon in Columbus?

Accepted Answer

The heating season, roughly October through March, when houses stay closed and warm air rising indoors draws harder on the soil. A result from those months is a stronger basis for a decision than a summer short-term test. Central Ohio sits in IECC climate zone 5A, a colder zone than Cincinnati's 4A, so the closed-house season runs long. Warm air rising through a heated house leaves the lowest level at slightly lower pressure than the soil, and that difference pulls soil gas inside; in mild weather with windows open the effect fades. Ohio's protocol already requires closed-building conditions for short tests, which narrows the gap, but it cannot recreate January in July. Two practical cautions: do not run a short test during a severe storm or sustained winds of 30 mph or more, and if you travel mid-test, keep the heat running normally. A long-term test of more than 90 days captures the whole swing. See the heating-season testing plan.

Question 31

How does my furnace or air conditioning affect radon?

Accepted Answer

A basement furnace can spread basement air through the whole house, and anything that exhausts air, like dryers, range hoods, and bath fans, can lower indoor pressure and pull in more soil gas. A good mitigation design accounts for both. Ohio's standards build HVAC into the job. The pre-install inspection notes systems that run continuously, and where natural-draft gas appliances share the basement, a backdraft test is required right after the fan is switched on, with any backdrafting corrected before the system goes into service. Test conditions account for HVAC as well: during a short-term test the furnace or air conditioner runs normally, but the air handler should not be set to run continuously unless it is labeled for radon control. Air conditioner condensate lines that drain beneath the slab need a trap, a reroute to a trapped floor drain, or a pump, so the fan does not pull air through them. After a furnace replacement or duct change, retest, because the pressure picture in the basement may have shifted.

Question 32

Does a radon contractor have to be licensed in Ohio?

Accepted Answer

Yes. Under ORC 3723.02, a company doing radon mitigation needs an Ohio Department of Health mitigation contractor license, the person supervising on site needs a mitigation specialist license, and anyone testing for others needs a tester or specialist license. ODH's Radon Education and Licensing Program, headquartered on North High Street in Columbus, licenses mitigation contractors, mitigation specialists, radon testers, radon labs, and training providers. Its Hire a Professional page links a licensure map for finding testers and mitigation contractors near you. Specialist licenses run two years, with 16 hours of continuing education in that span, 8 of them on mitigation. Out-of-state licensees may work in Ohio up to 90 days a year, and only after notifying ODH. National credentials such as NRPP are useful, but the Ohio license is the legal requirement. Every Ohio proposal must list the license numbers of the specialist and the contractor, and licensees report each job's before and after results to ODH every quarter. All mitigation contractors you work with here hold the Ohio license. See how to check a license.

Question 33

Can radon come back after a system is installed?

Accepted Answer

Levels climb again when the fan fails, a sump cover or seal is disturbed, or the house changes through an addition, a basement finish, or waterproofing. A working, maintained system holds its result, which is why Ohio says to retest every two years. Watch the gauge. Ohio requires every active system to have a monitor, and a manometer has to be marked with its reading at start-up, so any change is easy to spot; liquid sitting level on both sides of a U-tube means the fan is not pulling. Fans wear out, and the EPA notes many last five years or more. Seals fail more quietly, most often after someone lifts the sump cover to service the pump and does not reseal it with silicone the way Ohio's standard expects. Renovations are the third cause: a new bathroom rough-in cut through the slab or a crawl-space addition can open a path the original design never covered. Retest after any of these. See is my system working.

Question 34

My test came back between 2 and 4 pCi/L. Now what?

Accepted Answer

The EPA recommends considering a fix in that range, since no level is risk-free. Many Central Ohio households run a long-term test of more than 90 days across the heating season to learn the year-round average before deciding. The EPA's lifetime risk table puts the gap in plain numbers. Among 1,000 people who never smoked, about 4 could get lung cancer from a lifetime at 2 pCi/L and about 7 at 4 pCi/L; among smokers, about 32 and 62. A summer short-term result in the 2 to 4 band is the weakest basis for a decision, because a closed winter house usually pulls harder on the soil. A long-term device set out in November and collected in February answers the question for most Columbus homes. Weigh who uses the lowest level, too: a basement bedroom or a home office down there changes the math. Our decision guide for borderline results walks through each band.

Question 35

How do I know if my radon system is working?

Accepted Answer

Look at the gauge or monitor on the pipe. Ohio requires every active system to have one, and a manometer must be marked with its reading at start-up. If the liquid has leveled out or the alarm is on, the fan is not pulling. Retest every two years. A U-tube manometer shows suction as a difference in liquid height between its two sides. Compare today's reading with the start-up mark; a large drift either way deserves a call, and level liquid means no suction at all. Electronic monitors have to be wired to circuits that are not switched and must reset on their own after a power outage. Check the obvious as well: the fan in the attic or on the outside wall should be running, and the breaker labeled RADON REDUCTION SYSTEM should be on. A healthy gauge proves the fan is moving air; it does not prove the air you breathe is below 4 pCi/L. That is why Ohio installers must advise retesting at least every two years and after major changes. Our repair service covers fans, gauges, and seals.

Question 36

Why is my radon fan making noise?

Accepted Answer

A new hum or whine usually means worn bearings, a rattle usually means a loose mount or coupling, and a gurgle usually means condensation collecting in the pipe. None is dangerous, but a failing fan should be replaced before it stops. Condensation is routine in Central Ohio winters, when warm, damp soil gas meets a pipe running through a cold attic or up an outside wall. Ohio's standards require the piping to drain that water back down to the ground beneath the slab or membrane and require fans to sit in vertical runs so water cannot pool in the housing; a sag in a horizontal run defeats both. Vibration noise usually traces to the mounting, which the standards say should limit transfer to the framing, or to couplings that have worked loose. A fan mounted inside the living space, which the current Ohio standard does not allow, will always be louder than one in the attic or outdoors. See the fan replacement guide.

Question 37

I just bought a Columbus home and the radon test was high. What first?

Accepted Answer

Keep the test report, then have a licensed mitigation specialist inspect the house and write a proposal. Ohio requires that inspection and a floor plan before any written quote, and a signed proposal before work starts. If the seller gave a credit instead of installing a system, the scoping is now yours. Ask for an Ohio-licensed mitigation contractor and specialist, and check both licenses on ODH's Hire a Professional page. The proposal should list both license numbers, the planned scope and completion date, the installed price, an estimate of annual operating cost, and either a guarantee to bring the average below 4 pCi/L or an explanation of why there is none. Keep living in the house normally in the meantime; radon risk builds over years, not weeks. After the install, schedule the post-mitigation test between 24 hours and 30 days after the fan starts. Our guide to checking an Ohio radon license covers the paperwork, and you can contact us to get the visit on the calendar.

Question 38

My neighbor's radon test was low. Do I still need to test?

Accepted Answer

Yes. Houses side by side can read very differently because foundation type, cracks, sumps, and how each house is heated and ventilated all vary. EPA and Ohio guidance both say to test every home. Central Ohio streets are often mixed. In Worthington or Upper Arlington, a 1950s ranch on a slab can sit beside a 1930s house with a full basement and a later addition over a crawl. In Hilliard and Dublin, neighbors built from the same plan can differ by a patched slab, a sump pit, or a finished lower level. The ground itself changes over short distances in glacial country, where sand and gravel pockets sit beside tight clay. ODH says its own county and ZIP maps are for education only and that testing is the only way to know. A kit costs $15 to $30, and Ohio homeowners can order one free. See how to use a test kit.

Question 39

Why is my radon still high after mitigation?

Accepted Answer

Usually the suction does not reach the whole slab, an opening was missed, the fan is wrong for the soil, or the test was not run correctly. Ohio proposals must state a guarantee and its conditions or explain why there is none, so start there. Check the test first. The post-mitigation test should run between 24 hours and 30 days after activation, under closed-house conditions, in the same spot as the original test, with the system running, and not during a windstorm. If the test holds up, look at the design. Ohio's standards call for a communication test wherever the material under the slab is unknown; slabs poured in sections, interior footings, and dense clay can block suction, and a second suction point often solves it. Openings that could not be sealed must have been disclosed in writing. A sump with a working pump should not be the primary suction point. Old stone foundations in Clintonville and German Village are the classic hard case. See the Clintonville stone basement scenario.

Question 40

Will a radon system make my Columbus home harder to sell?

Accepted Answer

Usually not. A documented system with a recent low result answers the radon question before a buyer asks it. Ohio's disclosure form asks sellers about known radon and any mitigation, so paperwork showing the problem was fixed helps. Buyers and their inspectors look for evidence. Ohio's standards require a closeout package with the floor plan drawing, pre- and post-mitigation test data, contracts and warranties, a system description, and the installer's license number, and the drawing has to be available to future owners on request. A system with a marked gauge, a working monitor, labeled pipe, and a fan outside the living space reads as compliant at a glance. Trouble starts when a system cannot be documented or visibly misses the standard, such as a fan hanging in the basement or a discharge low on the wall beside a window. If a sale is likely in the next year, retest now so the number is fresh. See radon in a Columbus home sale.

Question 41

My radon test came back at 6.5 pCi/L. What does that mean?

Accepted Answer

It is above the EPA action level of 4 pCi/L, and it is not an emergency. For a home not being sold, Ohio's testing strategy calls for a second short-term or a long-term test at that level, then a fix if the average stays at 4 or more. On the EPA's lifetime risk table, 6.5 sits between the 4 and 8 pCi/L rows, where about 7 to 15 of every 1,000 never smokers, and about 62 to 120 of every 1,000 smokers, could get lung cancer from a lifetime of exposure. That is why the answer is to fix it this season, not to move out. If the number came from a real estate test, Ohio's strategy is simpler: 4.0 or higher means fix the home, without a second test. Check how the result was produced before acting on it. The report should show start and stop times, the device and its serial number, the tester's Ohio license number, and where the device sat. A kit left in a laundry room or beside the sump does not meet Ohio's placement rules. See how to read an Ohio radon report.

Question 42

Who pays for radon mitigation in a Columbus home sale?

Accepted Answer

No Ohio rule assigns it. It gets negotiated: the seller installs a system before closing, the seller gives a credit, or the buyer takes it on. Get a written scope before the inspection response deadline so the number on the table is real. A system installed before closing, with the post-mitigation result in hand, is usually the cleanest outcome for a buyer, because Ohio's standards then hand over a closeout package, a floor plan, and a license number to call. A credit works when time is short, but it should be sized from a written proposal rather than a guess; a crawl space or a second suction point can move the price from the $1,200 to $2,400 range into the $1,800 to $3,500 tier. If the seller installs, the buyer can ask for the post-mitigation test to be run by an independent Ohio-licensed tester, which the rules allow. Sellers can skip the scramble entirely by testing before listing. See the real estate radon service.

Question 43

Do I have to disclose radon when selling a house in Ohio?

Accepted Answer

Ohio's residential property disclosure form asks whether you know of previous or current radon gas on the property, the level if known, and any mitigation. It covers what you know; it does not require a test before listing. The form is prescribed under OAC 1301:5-6-10 and ORC 5302.30, and radon is item 4 of its hazardous materials section, next to lead-based paint, asbestos, and urea-formaldehyde insulation. The choices are yes, no, or unknown. If you hold a report, an old buyer's test, or a system in the basement, the honest answer is yes, with the level and what was done about it. The form itself tells buyers to do their own due diligence on radon and points them to EPA and Ohio Department of Health resources, so most Central Ohio buyers test anyway. That makes a pre-listing test a strategy call: learn the number on your schedule, or let the buyer's inspector learn it on theirs. For questions about your specific disclosure, ask your agent or attorney. See pre-purchase testing.

Question 44

Can radon cause lung cancer in people who have never smoked?

Accepted Answer

Yes. The EPA calls radon the leading cause of lung cancer among non-smokers and estimates that about 2,900 of the roughly 21,000 US radon-related lung cancer deaths each year occur in people who never smoked. The EPA's lifetime table for never smokers: at 4 pCi/L, about 7 of every 1,000 people exposed over a lifetime could get lung cancer; at 8 pCi/L, about 15; at 20 pCi/L, about 36. For smokers the figures are far higher, about 62, 120, and 260 at the same levels, because the two exposures compound. The Ohio Department of Health gives the same message: radon is the number one cause of lung cancer in non-smokers and the second in smokers. In Franklin County, where tested homes had an estimated mean of 9.5 pCi/L from 2008 to 2017, those rows are not abstract. Lowering the level lowers the risk from that point on. See is radon a problem in Columbus.

Question 45

Should I test for radon before finishing my basement?

Accepted Answer

Yes, and before framing. The EPA advises testing before a major renovation like finishing a basement and again afterward. If a system is needed, planning the pipe route while walls are open beats cutting into new drywall. Ohio's standards shape the plan. The fan cannot sit in the basement or any conditioned space, so the pipe has to reach an attic, a garage that is not under living space, or the outside wall, and the route has to leave access to anything that needs service. Exposed pipe gets a RADON REDUCTION SYSTEM label on each floor. If the sump stays in the finished space, its cover must remain removable, clear enough to see the pump, and sealed with silicone. Frame a chase into the plan and keep the floor-wall joint reachable for sealing. After the finish is complete and the house is back to normal, retest the new rooms. See finishing a basement in Columbus.

Question 46

My new house has a radon pipe but no fan. What does that mean?

Accepted Answer

It is a passive radon-resistant rough-in. It relies on natural draft, which the EPA rates at 30 to 70 percent reduction versus 50 to 99 for a fan system. Test the house; if it reads 4 pCi/L or more, adding a fan activates it. Look for a 3- or 4-inch PVC pipe rising from the slab through a closet or utility room, often labeled, and for a junction box in the attic, which the EPA recommends for a future fan. Check where the pipe ends: one that stops in the attic instead of passing through the roof is not a working system in either mode. Activation is licensed mitigation work in Ohio (setting aside the owner exemption), and the finished system has to meet the Ohio standards: a fan in the attic, a garage not under living space, or outside; a monitor; labels; and a discharge above the eave and away from windows. On the site's price list, activation runs $700 to $1,200. See passive pipes in new Delaware and Union county homes.

Question 47

Should I test my well water for radon?

Accepted Answer

If the house is on a private well and the air test is elevated, it is worth testing the water too. The EPA says soil gas is usually the much bigger risk, and most water risk comes from radon released into the air by showers and laundry. Private wells are common on the rural edges of the service area, around Granville, Johnstown, Galena, Sunbury, Marysville, and Plain City. Ohio's private water rules in OAC 3701-28 cover well construction, permits, and sampling through local boards of health but set no radon limit, so a well is never checked for radon unless the owner asks. Public water drawn from rivers and reservoirs is not usually a radon concern, and a public system that uses groundwater can answer questions about its own supply. If a water result comes back high, point-of-entry treatment covers the whole house: the EPA rates aeration at 95 to 99 percent removal and granular activated carbon at 85 to 95 percent for moderate levels, with by-products building up in the carbon. See radon in private wells.

Question 48

How long before radon makes you sick?

Accepted Answer

There is no point at which it suddenly makes you sick. Radon causes no symptoms; its risk is lung cancer that grows with the level and the years of exposure. That is why a high result calls for a fix this season, not an evacuation. The EPA's risk tables are written in terms of a lifetime of exposure, which is the honest frame. A family that finds 8 pCi/L in March and has a system running by April has changed very little about its lifetime risk compared with fixing it the same day; what matters is the years that follow. Two groups gain the most from moving quickly. Smokers face much higher risk at every level, about 120 per 1,000 at 8 pCi/L on the EPA table against about 15 for never smokers. And anyone who sleeps or works on the lowest level spends the most hours where readings run highest. In the meantime, use the house normally, and consider moving a basement bedroom upstairs until the fix is in. See radon and lung cancer.

Question 49

Is it okay to live in a house with radon?

Accepted Answer

Every house has some radon; outdoor air averages about 0.4 pCi/L. The question is how much. Below 2 pCi/L, retest every two years. Between 2 and 4, the EPA says consider fixing. At 4 or more, fix it, and keep living there normally while it is scheduled. In Central Ohio a high result is common rather than unusual: every county in the region is EPA Zone 1, and Franklin County's tested homes had an estimated mean of 9.5 pCi/L from 2008 to 2017. That also makes the fix routine. The EPA rates active sub-slab suction at 50 to 99 percent reduction, and Ohio's standards govern how it is installed, labeled, and verified. While an install is being scheduled, small steps help at the margins: spend less time in a basement room if you can, and keep up normal ventilation. The design target written into Ohio's standards is a level as low as reasonably achievable in every part of the house, not just a pass under 4. See what your test number means.

49 answers about radon mitigation in Columbus

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