TriMark Home Inspection Services of North Carolina

...because Home Inspection matters

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Radon Testing

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What Is radon?

Radon is a naturally occurring radioactive gas that can cause lung cancer with repeated long-term exposure.   Radon gas comes from the decay of radioactive materials in the ground beneath your home and enters through openings in the building shell.   The Environmental Protection Agency ( has set an Action Level of 4.0 picoCuries of radon per Liter of air (4.0 pCi/L) as the number above which some action should be taken to lower the indoor radon levels.  For more information you can download: EPA's Citizens Guide to Radon

TriMark can place Charcoal canisters in conjunction with a home inspection as the most cost-effective means of testing a home for radon.   The canisters are exposed for a minimum of two (2) days and a maximum of seven (7) days, and then returned to Radon Testing Corporation of America (RTCA) in a prelabeled, prepaid Priority Mail cardboard box.  RTCA should email the Site Radon Inspection Report to TriMark within 1 business day after they received the completed test.  We will then email you the results and forward the report.

EPA Guidelines for Radon Test:

All windows and exterior doors must be kept closed for 12 hours before the start of the test and keep them closed for the entire test period.  Opening and closing of exterior doors should be restricted to normal entry and exit.  Do not use any external air exchange systems (e.g., window fans, whole building attic fans, window air conditioning units with the outside air damper open, etc.) for 12 hours before and during the test period.   Heating or central air conditioning systems must be operated on their normal settings temperature between 64 - 76 degrees.  
Test result reports are normally emailed to TriMark in pdf format within 1 business day from the canister receipt date.  The report will then be transmitted to the client via email.

Cost for Radon Test with Charcoal canisters

$150 — Canisters are placed at the time of the home inspection and retrieved by TriMark at the end of test period.   TriMark completes the test site paperwork and mails the charcoal canisters to the radon test laboratory for processing.

$50 — Canisters are placed at the time of the home inspection and retrieved by the client or client's agent at the end of test period.   The client or agent follows the EPA guidelines to complete the test: seals the charcoal canisters, completes the test site paperwork. then places the cansiters with the completed test information card and mails the radon kit in a prelabeled, prepaid Priority Mail cardboard box to the radon test laboratory for processing.

Overview Guidelines for Indoor Radon Level Test with RTCA Professional Radon Test Kit

Buyer/Client to complete the test document