Flagstaff, AZ Radon Mitigation and Testing

Q: What is the average radon level in Flagstaff, AZ?

Based on 5 user-submitted tests, the average radon level is 6.00 pCi/L.

Q: What EPA Radon Zone is Flagstaff in?

Flagstaff is in Coconino County, EPA Zone 2.

Q: How much does radon mitigation cost in Flagstaff?

Radon mitigation typically costs between $800 and $2,000. Most standard systems fall in the $1,000-$1,500 range.

Avg: 6.00 pCi/L

Coconino County

EPA Zone 2

5 user tests

Elevated at 7,000 feet in Coconino County, Flagstaff sits over volcanic rock formations of the Colorado Plateau that create significant radon potential. With an average level of 7.13 pCi/L across multiple zip codes, readings substantially exceed the EPA action level of 4.0 pCi/L. The combination of volcanic geology and high altitude creates conditions where radon testing and mitigation are essential for all area homeowners.

6.00

pCi/L average

Above EPA Action Level

Based on 5 user-submitted radon tests for homes in Flagstaff, AZ. The EPA recommends taking action at or above 4.0 pCi/L.

4.0 EPA

10+

Flagstaff, AZ Radon Mitigation

Professional radon mitigation is the most effective way to permanently lower radon levels and protect your household.

Flagstaff, AZ Radon Testing

Finding qualified radon testing professionals is the first step toward protecting your home.

Flagstaff, Arizona Radon Levels

User-submitted radon test readings from homes in the Flagstaff area.

Radon Level	City	Home Age	Foundation	Submitted
6 pCi/L	Flagstaff, AZ	0-20 Years	No Basement/All Crawl Space	Oct 2023
4 pCi/L	Flagstaff, AZ	21-50 Years	No Basement/All Slab	Jul 2020
9 pCi/L	Flagstaff, AZ	0-20 Years	—	Mar 2020
7 pCi/L	Flagstaff, AZ	21-50 Years	No Basement/All Slab	May 2019

Have a radon test result for Flagstaff? Submit your reading to help other homeowners.

Flagstaff Radon Facts

Key details about the radon risk profile for Flagstaff and the 86001 zip code area.

EPA Radon Zone

Zone 2 — Moderate Risk

County

Coconino County, AZ

Zip Code

86001

Predicted Screening Level

2–4 pCi/L (Zone 2)

Avg. User Submitted Level

6.00 pCi/L

User Tests Submitted

Flagstaff and the 86001 zip code are located in Coconino County, which has an EPA assigned Radon Zone of 2. A radon zone of 2 predicts an average indoor radon screening level between 2 and 4 pCi/L. The EPA recommends testing every home regardless of zone classification.

Radon FAQ for Flagstaff, AZ

What is the average radon level in Flagstaff, AZ?

Based on 5 user-submitted tests, the average radon level in Flagstaff is 6.00 pCi/L. This exceeds the EPA's recommended action level of 4.0 pCi/L, and radon testing is recommended for all homes in the area.

What EPA Radon Zone is Flagstaff in?

Flagstaff and the 86001 zip code are in Coconino County, which has an EPA assigned Radon Zone of 2. A zone of 2 predicts an average indoor radon screening level between 2 and 4 pCi/L.

How much does radon mitigation cost in Flagstaff?

Radon mitigation in Flagstaff typically costs between $800 and $2,000. Most homes with standard basements can be mitigated with a sub-slab depressurization system in the $1,000–$1,500 range. Factors that can increase cost include complex foundations, crawl spaces, or very high radon levels.

Should I test for radon if I'm buying a home in Flagstaff?

Yes. Radon testing should be part of every home purchase. A short-term radon test is typically included as part of the home inspection process and costs $150–$250. If elevated levels are found, you can negotiate mitigation as part of the sale.

Most Active Radon Markets in Arizona

Cities with the most user-submitted radon test data in the state.

City	Avg User Radon Level	Submissions
Prescott	6.79 pCi/L	14
Scottsdale	7.75 pCi/L	12
Phoenix	5.40 pCi/L	10
Mesa	6.40 pCi/L	5
Flagstaff	6.00 pCi/L	5
Tucson	5.25 pCi/L	4
Payson	6.67 pCi/L	3
Glendale	6.50 pCi/L	2
Peoria	3.00 pCi/L	2
Prescott Valley	4.00 pCi/L	1
Gilbert	3.00 pCi/L	1
Tempe	3.00 pCi/L	1