Cook County. Illinois radon mitigation license RNM2018212
Radon mitigation in Palos Heights
Palos Heights is Cook County, so the cheap test is the free mail-in kit from the Cook County Department of Public Health. The request page says to expect delays, so order it early. A reusable detector is the other way to get a number, and it keeps reporting through the seasons.
Text Bill the number and he’ll tell you what it means, free. If it comes back high, he comes out from Tinley Park, looks at the foundation, and gives you the price. Then the work gets scheduled.
What licensed tests in Palos Heights show
The numbers below come from the IEMA feature layer that feeds the public radon map. We read it on October 14, 2026. The service note calls the extract a July 18, 2022 pull. A row had to be marked valid and had to include a numeric result. The same address can appear again if someone tested again. IEMA describes the map itself as the highest measurement per address, drawn from 2003 to 2019, so this count is a different cut of the same file. Our other town pages also leave out records with a mitigation system noted, so their county shares differ a little from the ones here.
Where the city name is Palos Heights, 170 of 454 valid tests were 4.0 pCi/L or higher. That is 37.4 percent. ZIP 60463 produced the same 170 and 454. In that layer the Cook County share is 20.6 percent, from 17,359 results at or above 4.0 out of 84,118 valid tests.
People ordered these tests. The file is not a door-to-door census, and a home that already has a fan can still be in it. The June 2024 EPA county file marks Cook County as Zone 2. A zone covers a county. It does not forecast the air under one slab. A test of the home is the only way to know.
The ground under Palos Heights
The Forest Preserves of Cook County list Palos Heights among the Cal-Sag Trail communities, with the others named as Alsip, Blue Island, Calumet City, Dolton, Lemont, and Riverdale. Trail access in the city is at Lake Katherine Nature Center, which the preserve district says the City of Palos Heights owns, at 7402 Lake Katherine Drive. The same page says the trail runs east from Sag Quarries near Lemont across the south suburbs. That puts the city on the Sag, which is a valley story, not a slogan.
Illinois State Geological Survey Guidebook 37 calls that valley the south arm of the Chicago Outlet. Glacial Lake Chicago cut a Y-shaped passage through the end moraines. The valley floor is up to 1 mile wide and as much as 100 feet lower than the crest of the moraine beside it. The south arm, the Sag Valley, has no major river today. It carries the Calumet-Sag Channel. The guidebook says the surficial geology in and near the outlet is primarily till, or a thin cover on till, and that bedrock along the valley floor is exposed or only shallowly buried. Regionally that rock is Silurian dolomite of the Racine Formation.
A 2004 Cook County geologic atlas from the same survey, written for planning, describes the county landforms as glacial. It names nearly level plains that were once lake beds, moraine ridges that mark where the ice stopped, and beach ridges left by glacial Lake Chicago. The atlas also says glacial clay, silt, sand, and gravel cover the bedrock by as much as 300 feet, and that Silurian dolomite is the rock at the bedrock surface across nearly the whole county. The upper dolomite has fractures, crevices, and solution cavities that yield water to wells. Those openings are a path for groundwater. They are also a path soil gas can use. The atlas is a county picture. It does not measure the cover under a Palos Heights foundation.
Radon-222 is what you get when radium-226 decays. Radium-226 is a step in the uranium-238 chain, which is ordinary trace material in soil and rock, not a local ore. The EPA fact sheet gives this radon a half-life of 3.8 days. That is enough time for the gas to cross pore space in till or a fracture in dolomite and enter a basement. It is not enough time for last winter gas to still be the problem next summer. When the furnace runs, indoor air gets buoyant and leaks out high in the home. Pressure at the lowest level drops, and soil gas is drawn in. EPA reduction guidance names that winter pull the stack effect.
Lake Katherine, the Sag, and the moraine explain why this city looks the way it does. They do not assign a pCi/L to your home.
Palos Heights homes, from the Census
Census QuickFacts puts the city at 12,084 people on the July 1, 2025 figure, with 93.4 percent of housing owner-occupied in the 2020 to 2024 survey. CMAP counted this housing in a June 2026 snapshot of that survey. Median year built is 1976. Units from 2010 or later number 203, which is 4.0 percent. Units from 1990 to 2009 number 1,226, which is 24.3 percent. Units from 1970 to 1989 number 1,768, which is 35.1 percent. Detached homes are 3,030, or 60.1 percent. Attached single-family homes are 1,108, or 22.0 percent.
The statewide passive-pipe requirement, as the Will County radon page states it, applies to new one-family and two-family construction after June 1, 2013. With a 1976 median and only 4.0 percent of units from 2010 on, a pipe with no fan is uncommon here unless the home is one of the newer ones. The 2010 bin still includes homes finished before the rule, so the year on the tax bill is not proof. A photo is.
How the kits and the detectors fit together is written up on the radon testing guidance page. A test for a sale belongs with an Illinois-licensed measurement professional.
Nearby pages
The pages on either side of Palos Heights:
Palos Heights questions
Where does a Palos Heights homeowner get a radon kit?
Palos Heights is in Cook County. Order the free suburban kit on the Cook County health department site, and plan for delays. Send the lab report to Bill and he will read it at no charge. For a sale, use an Illinois-licensed measurement professional.
Why is the Palos Heights share higher than the Cook County share?
In the July 18, 2022 layer, 37.4 percent of 454 valid Palos Heights tests were at or above 4.0 pCi/L, against 20.6 percent of 84,118 valid Cook County tests. The people who tested chose to test, and a home can appear more than once. The gap is context. It is not a prediction for the home you live in.
Does the Sag Valley or the moraine decide my radon level?
No. Guidebook 37 describes a valley floor up to a mile wide, cut as much as 100 feet below the neighboring moraine, with till at the surface and dolomite at or near the valley floor. The gas still starts as uranium decay in soil and rock, and the home still has to be measured. The valley does not set the reading.
Most Palos Heights homes predate the 2013 pipe rule. Does that change the job?
The median year built is 1976, and only 4.0 percent of units date from 2010 or later. Passive piping applies to one-family and two-family homes finished after June 1, 2013. Older homes get a full system, designed after Bill looks. If you do have a white pipe and no fan, send a photo before anyone assumes it can be activated.
Sources
- IEMA-OHS, Radon in Illinois
Map disclaimer. Licensed measurements, 2003 to 2019, highest test per address. Every home should be tested.
- IEMA licensed-measurement layer
July 18, 2022 pull. Palos Heights counts are valid numeric tests queried October 14, 2026, not the map address totals.
- IEMA-OHS Public Radon Dashboard
The public view of the same layer.
- EPA radon zones, June 2024 county file
Cook County is Zone 2 in this file.
- EPA Facts about Radon
States a 3.8-day half-life for radon.
- EPA guide, radon in detached homes
Cited for radium-226 as the parent of radon-222, and for soil gas as the usual indoor source.
- EPA approaches to radon reduction
Cited for the winter stack effect that pulls soil gas in at the foundation.
- ISGS Guidebook 37, Chicago Outlet
Sag Valley as the south arm of the Chicago Outlet. Floor width, relief against the moraine, till, and shallow dolomite.
- Forest Preserves of Cook County, Cal-Sag Trail
Lists Palos Heights, and Lake Katherine Nature Center at 7402 Lake Katherine Drive, owned by the city.
- ISGS, Geologic Atlas of Cook County for Planning Purposes, 2004
Leetaru, Sargent, and Kolata. Glacial cover up to 300 feet. Silurian dolomite at the bedrock surface, with fractures and solution cavities.
- CMAP Community Data Snapshot, Palos Heights, June 2026
Palos Heights year built and housing type. Median year built 1976. Only 4.0 percent of units are from 2010 or later.
- U.S. Census Bureau QuickFacts, Palos Heights city
July 1, 2025 population 12,084. Owner-occupied rate 93.4 percent.
- Suburban Cook mailed radon kit
Free mailed kits for suburban Cook residents. Expect delays.
- Will County radon program page
Quoted for the statewide passive-pipe date of June 1, 2013, limited to new one-family and two-family homes.
- IEMA-OHS, What is radon
The 4.0 pCi/L action level, and the statement that only a test knows a Palos Heights home.