Radon Testing Services in Grand Junction, CO

Radon is a naturally occurring radioactive gas released as uranium in soil and rock breaks down. It is invisible and odorless, so testing is the only way to know whether it is entering a property. Grand Junction and Mesa County are in the EPA's highest-potential Radon Zone 1. Roughly half of tested local homes exceed the EPA action level of 4.0 picocuries per liter (pCi/L), and some neighborhoods have recorded averages as high as 9.1 pCi/L. Individual results vary—even neighboring homes can have different levels.

Grand Junction Radon Mitigation provides professional radon testing for homes, real estate transactions, commercial and multi-unit buildings, and schools. We use continuous radon monitors (CRMs), charcoal canisters, and alpha track detectors, with device placement and testing conditions based on EPA protocols. Reports explain the measured level, test conditions, and whether follow-up testing or mitigation should be considered.

Grand Junction Radon Mitigation is committed to improving indoor air quality for Western Colorado homes and businesses with reliable testing, mitigation, repairs, and customized solutions. Our team offers certified, dependable service, and provides quality workmanship.

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Professional Radon Testing for Homes and Buildings

The right testing plan depends on the property's use, foundation, size, and timeline. We tailor testing for occupied homes, real estate transactions, commercial properties, multi-unit buildings, and institutions.

Residential Radon Testing

We test single-family homes, condos, and townhomes using short-term or long-term methods. Short-term testing (typically 48 hours to 7 days for our service) provides a timely screening. Long-term testing of 90 days or more captures seasonal changes and provides a better picture of average exposure.

Devices are generally placed on the lowest livable level, such as a finished basement or main floor. Slab-on-grade and crawl-space homes are tested in the lowest occupied room, not automatically inside an unfinished crawl space. If results reach or exceed 4.0 pCi/L, the EPA recommends fixing the home.

Real Estate and Home-Buyer Radon Testing

Buyers and sellers often need results within an inspection or contract deadline. We typically use a 48-hour continuous radon monitor for real estate testing, following closed-house conditions and documenting device placement. CRMs record hourly readings and can identify certain test disturbances, making them useful when test integrity and timing matter.

We provide a written report that buyers, sellers, agents, and other transaction parties can review. Elevated results can inform negotiations about mitigation, repairs, or a credit before closing. Colorado residential sale contracts include a radon warning, and sellers have disclosure responsibilities; confirm current requirements with the appropriate real estate or state professional.

Commercial and Multi-Unit Building Testing

Offices, retail spaces, apartment buildings, and other large properties may need several test locations. We plan sampling around square footage, floor plans, ground-contact areas, HVAC zones, and occupancy patterns. Radon levels can differ between units and rooms, so a single reading may not represent an entire building.

For multi-unit properties, we determine an appropriate sample of units and spaces rather than assuming every unit requires the same approach. We coordinate access with owners or property managers and provide reports identifying locations that may need follow-up testing or mitigation.

Schools and Institutional Radon Testing

Schools, daycare centers, and other institutions require a structured plan because children and staff may spend extended periods in ground-contact or below-grade rooms. Testing locations can include frequently occupied classrooms, offices, and common areas. We account for building layout, ventilation schedules, and occupancy patterns when planning the test.

EPA guidance recommends testing frequently occupied ground-contact and below-grade rooms in schools. Retesting may be appropriate every few years and after major renovations or HVAC changes.

Radon Testing Methods

Short-term and long-term tests serve different purposes. We select the device and duration based on whether you need a quick screening, a year-round exposure picture, or detailed data for a real estate transaction or post-mitigation check.

Short-Term Radon Testing

Short-term tests run from 2 to 90 days under the general EPA definition; our typical short-term service is 48 hours to 7 days. They are commonly used for real estate transactions because they provide results within a practical inspection window.

The device is placed in the lowest livable area, and closed-house conditions are maintained before and during the test. Because radon changes with weather, season, and ventilation, a short-term result is a snapshot rather than a full-year average. A follow-up test may be useful when a result is near 4.0 pCi/L.

Long-Term Radon Testing

Long-term tests run for more than 90 days and may continue for several months or up to a year. They capture seasonal and day-to-day variation, making them useful for homeowners who want a more representative estimate of average exposure and are not working against a closing deadline.

The detector remains in a consistent location in the lowest occupied level. Long-term testing can be especially useful when a short-term result is borderline or when you want a fuller picture of normal living conditions.

Continuous Radon Monitoring

Continuous radon monitors (CRMs) are powered electronic devices that record radon concentrations at regular intervals, often hourly. They provide detailed readings over the test period and are commonly used for real estate testing and post-mitigation verification.

CRMs can also record environmental information such as temperature and movement, which may help identify disturbances or possible tampering. After mitigation, a CRM test can show whether levels have fallen below the EPA action level during the monitoring period.

Passive Test Devices and Professional Measurement

Charcoal canisters and alpha track detectors are passive devices: they do not require power and are sent to a laboratory for analysis after the test period. Charcoal canisters are generally used for short-term screening; alpha track detectors are generally used for long-term measurement.

Device	Typical duration	Power	Common use
Charcoal canister	2–7 days	No	Short-term screening
Alpha track detector	90+ days	No	Long-term average
Continuous monitor	Typically 48 hours or longer	Yes	Real estate testing and verification

Professional measurement also depends on correct placement and test conditions. We position devices at least 20 inches above the floor, away from drafts, exterior walls, high humidity, and other sources of interference. We handle setup and retrieval and document placement when required.

Where Radon Tests Are Placed

The correct location depends on the foundation, room use, and levels occupants regularly use. In general, testing focuses on the lowest livable level because radon typically enters from the soil beneath or around the foundation.

Basement and Lowest Livable Level Testing

We place a device in the lowest level that is currently used, or could reasonably be used, as living space. A finished basement or basement with the potential to be finished is generally an appropriate test location. An unfinished area used only for storage or mechanical equipment may not be the right location if it is not livable space.

The monitor is placed at least 20 inches above the floor and away from exterior walls, drafts, moisture, windows, doors, and HVAC vents. We also keep it clear of nearby objects so air can circulate around the device. These precautions reduce the chance that unusual airflow or moisture will affect the reading.

Main-Floor and Upper-Level Testing

If a home has no basement, or the basement is not used as living space, we test the main floor or lowest occupied level. This commonly applies to slab-on-grade homes and some split-level properties.

Upper floors are not usually the primary testing location because radon concentrations are generally highest near the ground. Additional testing may be appropriate when a specific concern or building layout warrants it. Devices on the main floor follow the same placement rules: elevated, away from exterior walls and drafts, and clear of open windows, fans, and vents.

Crawl Space and Slab-on-Grade Properties

For slab-on-grade homes, we test the lowest livable room above the slab. For homes with an unfinished crawl space, we generally test the occupied room directly above it rather than placing the device inside the crawl space. If a crawl space has been encapsulated or converted into usable living space, its treatment as a test area depends on how the space is used and configured.

Foundation design affects how radon may enter a home, but it does not eliminate the need to test. Homes with basements, crawl spaces, and slabs can all have elevated radon.

Multi-Unit and Commercial Sampling Plans

Larger properties need a sampling plan based on the number of units or rooms, building size, layout, and applicable guidance. We prioritize ground-floor and below-grade spaces in contact with soil and consider how HVAC zones and ventilation systems may affect readings.

A representative sample may be appropriate for some multi-unit properties, while other layouts require more locations. We identify the tested areas in the report so owners and property managers can see what the results do and do not represent.

Our Radon Testing Process

A consistent process helps produce useful results and gives you a clear record of the test.

Tell us whether the test is for a real estate transaction, a newly purchased home, routine home maintenance, or a commercial property. We ask about your deadline, property size, foundation type, occupancy, and any relevant renovations. This information helps us recommend an appropriate test and plan access.

We recommend a short-term test when you need results quickly, such as during a home inspection period. Long-term testing is more appropriate when you want a better picture of seasonal exposure and do not have a transaction deadline. We confirm the setup and retrieval schedule and account for whether the property is occupied or vacant.

For a short-term test, closed-house conditions should be maintained for at least 12 hours before the test begins and throughout the test period. In general:

Keep windows and exterior doors closed, except for normal entry and exit.
Operate the HVAC system in its normal, typical setting.
Turn off fans or whole-house ventilation systems that bring outdoor air inside, where required by the test protocol.
Avoid unusual ventilation, extended door opening, or major construction during the test.
Do not move, unplug, or interfere with the testing device.

These conditions help prevent outdoor air from diluting indoor radon and affecting the result. We explain the preparation requirements before testing begins.

We identify the appropriate lowest livable level and place the device according to the test protocol. Placement is away from drafts, exterior doors, windows, high-humidity areas, and HVAC vents, at least 20 inches above the floor and with clearance from nearby objects.

Depending on the test, we use a calibrated electronic monitor or a passive charcoal or alpha track device. The equipment remains undisturbed for the required duration. For documented testing, we record the location and may photograph the placement.

At the end of the test, we retrieve the monitor or collect the passive device for laboratory analysis. Electronic monitors provide digital readings; lab-analyzed devices require additional processing time.

The report identifies the measured average in pCi/L, test dates and duration, device location, and comparison with the EPA action level. CRM reports can also include hourly readings. We explain whether the result suggests no immediate action, follow-up testing, or mitigation.

Radon Test Results and Reports

A report should make the result understandable and show the conditions under which the measurement was taken. We review the findings with you so you can determine what to do next.

What Your Radon Test Report Includes

Depending on the device and service, the report includes:

Average radon concentration, measured in picocuries per liter (pCi/L).
Test start and end dates, times, and total duration.
Device location, room, and floor level.
Hourly readings for continuous monitor tests.
Relevant environmental or test-condition notes, including conditions that may affect accuracy.
Device or calibration information, where applicable.
A comparison with the EPA action level and recommendations for follow-up or mitigation.

For real estate transactions, documented placement and test conditions help agents, buyers, sellers, and other parties understand the result. Reports are prepared in accordance with applicable Colorado requirements. Confirm the exact state reporting requirements and any required credentials before publication.

How to Understand Your Radon Result

The EPA recommends fixing a home when the radon level is 4.0 pCi/L or higher. Radon risk does not disappear below that number, however, and the EPA advises considering a reduction when levels are between 2.0 and 4.0 pCi/L.

iPhone X	iPhone 8
Below 2.0	Lower level; continue periodic testing
2.0–3.9	Some risk remains; consider reducing the level and/or follow-up testing
4.0 or higher	EPA action level; mitigation is recommended

No radon level is considered completely risk-free. We explain the result and discuss whether a second test or mitigation assessment makes sense for the property.

When to Consider Follow-Up Testing

A single short-term test reflects conditions during that test window. A second test can help confirm a result near 4.0 pCi/L, and long-term testing can provide a more representative picture of seasonal exposure.

Consider retesting:

At least every two years, as a routine precaution.
After renovations or foundation work that may change radon entry or ventilation.
After installing or substantially changing an HVAC system.
Before selling a property, even if an earlier test was low.
Periodically after a mitigation system is installed, to confirm it continues to work.

Radon levels can change as a home, foundation, and ventilation system change. Previous results do not guarantee current levels.

What Happens if Radon Levels Are Elevated?

If results are 4.0 pCi/L or higher, the EPA recommends taking steps to reduce the level. A typical active mitigation system uses a vent pipe and fan to draw radon from beneath the home and discharge it outdoors above the roofline, away from windows and occupied areas.

System design depends on the foundation, including whether the home has a basement, crawl space, or slab-on-grade construction. After installation, a post-mitigation test checks whether radon has been reduced. Most installations are completed in about one day, depending on the property and system. The system's warning device or gauge should also be checked regularly. See our crawl space radon mitigation and radon system repair and fan replacement pages for related services.

Radon Testing Turnaround and Scheduling

The total timeline includes the test period, device retrieval, and report preparation. The method used affects how quickly results are available.

How Long Does Radon Testing Take?

Our typical short-term service runs for 48 hours to 7 days, with 48-hour continuous monitoring commonly used for real estate transactions. Long-term testing runs for 90 days or more and is intended to capture a broader range of conditions.

During a short-term test, closed-house conditions must be maintained. The monitor should remain in place and undisturbed for the full testing period.

How Quickly Will I Receive Results?

For continuous monitor tests, we aim to deliver results within 24 hours after the test is complete and the monitor is retrieved. Reports can include hourly readings, the average radon concentration, and a comparison with the EPA action level of 4.0 pCi/L.

Charcoal canisters and alpha track detectors must be sent to a laboratory, so results take additional processing time. We confirm the expected turnaround when the test is scheduled.

Scheduling Around a Home Sale or Inspection Deadline

Real estate testing must meet inspection and closing deadlines. Share your deadline when booking so we can coordinate monitor placement and pickup. With a 48-hour test, reports may be ready in 3–4 days, depending on availability. We can send results to the buyer, seller, or authorized contact. Book early to allow time to discuss mitigation if results are elevated.

Service Area: Grand Junction and Nearby Communities

We provide radon testing in Grand Junction and surrounding communities in the Grand Valley and Mesa County. The service-area list should reflect the locations the company actively serves:

Radon levels can vary between properties, even within the same community. Testing the individual home or building is the only way to determine its radon level.

Radon Testing Cost and What Affects Pricing

Factors That Affect Radon Testing Cost

Property size: Larger homes or buildings may require additional devices.
Test type and duration: Short-term, long-term, and continuous monitoring have different equipment and processing requirements.
Equipment: Continuous radon monitors provide detailed readings; passive devices may require laboratory analysis.
Purpose and turnaround: Real estate deadlines or documentation requirements may affect scheduling and service.
Foundation type: Crawl spaces or properties with multiple foundation types may need additional test locations.
Location: Travel distance within the service area may affect the quote.

Get a Radon Testing Quote

To request a quote, provide the property's location, approximate size, foundation type, reason for testing, and any deadline. For real estate transactions, have the inspection timeline available. Call us to discuss the property and arrange testing.

Why Choose Our Radon Testing Service

Testing should provide more than a number: it should follow an appropriate protocol and give you a clear explanation of what the result means. Grand Junction Radon Mitigation offers testing and mitigation through one provider, allowing customers with elevated results to discuss next steps without starting their search over.

Clear Instructions and Straightforward Reporting

Before testing, we explain the test duration, device placement, and closed-house requirements. Reports present the measured level in pCi/L and compare it with the EPA action level of 4.0 pCi/L. We explain the result in plain language and outline follow-up testing or mitigation options when appropriate.

Testing for Different Property Types

We adapt the sampling plan to single-family homes, condos, townhomes, multi-unit buildings, and commercial properties. Property managers may need documented results across selected units or occupied spaces, while larger commercial buildings may require multiple test points based on layout and HVAC zones.

Basements, crawl spaces, and slab-on-grade homes also require different placement decisions. We consider the property's construction and use when selecting test locations.

FAQs

Mesa County Public Health and the Colorado Department of Public Health and Environment (CDPHE) may offer free or low-cost radon test kits at certain times. Availability changes, so check directly with those agencies. DIY kits are also sold by some hardware stores. Follow the kit instructions carefully; for a real estate transaction, a licensed professional can provide documented testing.

Our typical short-term tests run 48 hours to 7 days. Long-term tests run 90 days or more. Continuous monitor results can generally be reported within 24 hours after retrieval, while passive devices sent to a laboratory take additional processing time.

The EPA recommends fixing a home when the measured radon level is 4.0 pCi/L or higher. For results between 2.0 and 4.0 pCi/L, the EPA says homeowners should consider reducing the level. A follow-up test may help clarify a result near the action level.

Retest at least every two years as a precaution, and after renovations, foundation repairs, or significant HVAC changes. Retest after mitigation as well, and periodically afterward to confirm the system continues to control radon.