Your Lincoln Radon Test Came Back Between 2 and 4 pCi/L

A Lincoln radon result of 3.1 or 3.4 or 3.8 pCi/L is the most awkward number a homeowner can get. It is not the clean reassurance a 1.2 would be, and it is not the clean instruction a 9.6 would be. It is the middle, and the middle is where a great many Lancaster County results actually land. Across the five years Nebraska DHHS reported to the Legislature, Lancaster County logged 19,828 radon measurements and averaged 3.6 pCi/L, which puts the county's own typical result squarely inside the band people find hardest to act on.

This guide is about that band. It covers what EPA actually says at those levels, why a Lincoln house is more likely to produce a middling number than a house twenty miles out of town, when a second measurement is worth doing before you spend money, and what changes if your house went up after Nebraska's radon construction law took effect. None of it substitutes for the test itself, and none of it will tell you what your house will read after mitigation, because that is a measurement rather than a prediction.

Why do so many Lincoln results land between 2 and 4 pCi/L?

Lancaster County's reported average across 19,828 measurements is 3.6 pCi/L. Look at the counties around it in the same Nebraska DHHS report and the picture shifts fast: Saunders County averaged 6.7, Saline 6.8, Seward 7.0, Gage 7.9. Douglas County, the other large county in the report, came in at 3.9. The two counties with test counts in the tens of thousands are also the two producing averages inside the 2-to-4 window, while the rural counties ringing Lincoln sit above the action level. Whatever drives that, the practical effect for a Lincoln homeowner is that the awkward middling result is the normal result here.

It is worth being precise about what a county average is and is not. The DHHS table counts measurements submitted, county by county, over a fixed window. It is not a survey of all homes, it is not weighted by foundation type, and it does not forecast any individual address. A Lincoln house with a deep full basement, a tight winter envelope, and an open sump crock can read several times the county average while a slab-on-grade ranch three streets over reads under 1. The county figure tells you what kind of market you are in. Your own test tells you what kind of house you are in.

• 4 pCi/L or higher: EPA recommends the home be fixed
• Between 2 pCi/L and 4 pCi/L: EPA recommends Americans consider fixing the home
• EPA states there is no known safe level of exposure to radon
• Nebraska DHHS reports that more than half of radon tests in the state come back above 4.0 pCi/L

Does EPA actually recommend fixing a home at 3.5 pCi/L?

EPA's published position has two lines and they say different things. The first: EPA recommends homes be fixed if the radon level is 4 pCi/L or higher. The second: EPA also recommends that Americans consider fixing their home for radon levels between 2 pCi/L and 4 pCi/L, because there is no known safe level of exposure to radon. So at 3.5 the agency is not telling you to fix it. It is telling you to consider fixing it. That is a genuine judgment call, and it belongs to the household rather than to a contractor or to a website.

What tips the call is usually the house and who lives in it rather than the decimal point. A finished basement bedroom somebody sleeps in every night is a different exposure picture than a basement opened twice a month for storage. How the house runs matters too, since a tightly sealed Lincoln home in January behaves differently than the same house with the windows open in May. And a plan to sell within a couple of years changes the math, because a disclosed 3.5 with nothing attached to it tends to become a line item in somebody's negotiation, while a documented system with a post-mitigation number attached usually does not.

Should I retest before I pay for a mitigation system?

Often yes, and specifically when the first number lands in the 2-to-4 band. A single short-term test is a snapshot of a few days, in one part of the house, under whatever conditions happened to prevail that week. In the middle band that snapshot is carrying a lot of weight for a decision that costs real money, so a second measurement over a longer stretch, in the room you actually occupy, is a reasonable step. If the first number had come back at 12, the retest argument would be much weaker, because nobody needs a confirmation run to justify acting on a reading three times the action level.

Nebraska treats measurement as a regulated activity, which matters when you choose who does the second test. Title 180, Chapter 11 of the Nebraska Administrative Code sets requirements for radon and radon progeny measurement and mitigation services and provides that a business must not conduct measurements without a radon measurement specialist. The same chapter requires mitigation businesses to keep records of the work performed, including pre-mitigation and post-mitigation measurements. Whoever you hire in Lincoln should be able to speak to their standing under that chapter without hesitating or changing the subject.

• Which room the first device sat in, and whether anyone spends real time there
• Whether the house was closed up normally for the whole test window
• Whether a sump crock, floor drain, or crawl space opening sits near the device
• Whether the result came out of a real estate deadline rather than a considered test

What would a system actually change in a Lincoln basement?

The mechanism is sub-slab depressurization. A suction point is cut through the basement floor, a gas-tight pipe is run from it and carried above the roofline, and a fan on that pipe holds the space under the slab at slightly lower pressure than the room above. Soil gas that would otherwise drift up through slab cracks, the sump crock, and the gap where the floor meets the foundation wall gets pulled out and discharged above the house instead. That is the whole idea. Everything else is detail about where to cut, how many points, which fan, and what gets sealed on the way.

Nebraska's construction statute is a useful specification even for a retrofit, because it describes the hardware the state considers adequate. Neb. Rev. Stat. 76-3504 calls for a minimum three-inch diameter ABS, PVC, or equivalent gas-tight pipe, terminating at least twelve inches above the roof surface and at least ten feet from windows or other openings less than two feet below the exhaust point, with sealed lids on sump pits and a label reading Radon Reduction System on each floor and in accessible attics. A retrofit is not governed by that statute, but a retrofit that ignores those dimensions is worth a second look before you sign.

• Minimum three-inch diameter ABS, PVC, or equivalent gas-tight pipe
• Termination at least twelve inches above the roof surface
• At least ten feet from windows or openings less than two feet below the exhaust point
• Sealed lids on sump pits, with a trapped inlet lid where the sump takes a floor drain
• A label reading Radon Reduction System on each floor and in accessible attics

What if my Lincoln house was built after September 1, 2019?

Then Nebraska's radon resistant new construction requirements should already have touched it. Neb. Rev. Stat. 76-3504 applies to new construction built after September 1, 2019 in the State of Nebraska that is intended to be regularly occupied by people. Section 76-3505 carves out three exemptions, and the one people ask about is the county clause: construction is not required to use radon resistant new construction if it is located in a county in which the average radon concentration is less than two and seven-tenths picocuries per liter of air, as determined by the department pursuant to section 76-3507. Lancaster County's reported average is 3.6. Lincoln does not qualify.

So a newer Lincoln house should have the gas-permeable layer, the soil-gas retarder, the vertical pipe, sealed sump lids, and an electrical circuit terminated in an approved box in the attic or wherever a fan would eventually go. What it does not have is a fan or a test result. The system as built is passive, meaning it works on stack effect alone and its performance varies with the season and the house. The circuit sits there because the state anticipated some of these homes would need activation. Test the living space, and if the number warrants it, the fix is often a fan on a pipe that already exists.