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Home/Radon Testing/Fairfax County/Herndon, VA
Radon testing
A continuous monitor on the lowest level that could be used regularly, read every hour for at least 48 hours. The written result comes the day we collect it.
4.9 rating, over 4,000 reviews NRSB-certified technicians Serving Fairfax County
A radon test in Herndon is $185, or $175 when it is added to a home inspection. That is the whole price: both visits, the monitor for the full 48 hours, and the written report with every hourly reading in it. The residential price covers one Herndon home or unit. Book online or call with the exact address, unit and access contact when the property is attached, rented or managed.
Day 1
Drop-off
A technician places it on the lowest level that could be used regularly, following EPA placement limits and the intended use of the space, inside a two-hour arrival window. With a home inspection, placement happens during the inspection visit.
48 hours
The house stays closed
For a short-term real-estate test, EPA guidance calls for closed-building conditions for at least 12 hours before the test and throughout the measurement. Windows stay closed, exterior doors open only for normal entry and exit, and the monitor logs hourly readings that help document the test conditions during the minimum 48-hour measurement.
Day 3
Pick-up and report
A technician picks the monitor up in another two-hour window and pulls the full record on the spot. The written report reaches you the same day.
NRSB-certified technicians. Our own team, certified by the National Radon Safety Board, not a subcontractor.
EPA testing guidance. Placement, closed-house conditions and the 48-hour minimum follow it, and your average is read against the EPA action level of 4.0 pCi/L.
Continuous monitors. Airthings Corentium Pro instruments, logging every hour for the whole test.
Appointment times are requests until our team confirms them. What the number means, how to prepare the property and the eight questions everyone asks are on the radon testing page; this page is about Herndon.
The Town of Herndon is in Fairfax County, which the EPA lists as radon Zone 1. The county label indicates broad potential but cannot give a Herndon residence's reading. Test the actual home and identify the lowest room that could be used regularly, whether it is a lower bedroom, office, den or planned living area.
The Town of Herndon documents its historic downtown and an ongoing review of local housing needs. Those community facts do not describe every Herndon mailing address or predict radon. For a downtown house, explain additions and the current lower-level layout. For an apartment or condo, give the exact building and unit, who can authorize entry, and a contact for both visits. Keep the selected space undisturbed during the measurement period.
Local background: Town of Herndon housing and community context, Virginia Department of Health radon guidance, EPA Map of Radon Zones.
01
Use the present interior layout rather than the building's age to discuss lower-room use.
02
Provide the unit and lobby instructions; another household and common areas are outside one residence's test.
03
Show the lowest room that may be used regularly and describe any planned change after closing.
Where we test in Herndon, and what to tell us
Downtown Herndon
In downtown Herndon, identify connected lower rooms and avoid active renovation dates.
Franklin Farm, Herndon Chase
For a Herndon apartment or condo, confirm the building, unit and authorized entry contact.
Four Seasons, Reston-Herndon Junction
For a detached or attached home with a Herndon mailing address, describe this home's own floor plan.
We do not install radon systems, so we have nothing to gain from your number. If the result is at or above the EPA action level of 4.0 pCi/L, you choose who fixes it. Once the system is in, we can test again and tell you what it reads.
Virginia's residential disclosure statute directs the seller's disclosure statement to say that the owner makes no representation about whether the property is in an EPA Zone 1 or Zone 2 locality. It directs buyers to use due diligence, including reviewing EPA, Virginia Department of Health and NRSB information and ordering a radon inspection before settlement as the contract allows.
Va. Code section 55.1-703. Current as of September 2026. General information, not legal advice.
Confirm the unit number, owner or manager permission, and entry for placement and retrieval. Keep the intended room accessible and notify other occupants not to disturb the monitor.
No. A residential appointment covers the selected apartment unit. Other units and common areas are outside that scope unless separately arranged.
Show every accessible low-level room that could support regular use, including a future office, guest room or recreation area. The technician selects the final location.
Plan the test outside the active move. Repeated door opening, furniture handling and traffic around the device can disrupt required conditions or physically disturb the monitor.
Book online or call (703) 450-6398.
Schedule a radon test Request a price
NextDay Inspect
46179 Westlake Dr, Ste 200, Sterling, VA 20165
(703) 450-6398
