The amount of radon in the air is measured in "picocuries per liter of air" or pCi/L. There are many kinds of low-cost "do it yourself" radon test kits you can get through the mail and in hardware stores and other retail outlets. Make sure you buy a test kit that will be analyzed by a laboratory listed by either of the two proficiency programs listed below:
The National Radon Proficiency Program (NRPP)
P.O. Box 2109
Fletcher, NC 28732
Toll Free: (800) 269-4174 or (828) 890-4117
Fax: (828) 890-4161
If you prefer, or if you are buying or selling a home, you can hire a trained measurer to do the testing for you. Make sure you hire a qualified radon tester listed with either NEHA or NRSB.
Radiological Health Program | James Madison Building, 7th Floor | 109 Governor Street, Room 730 | Richmond, VA 23219 | Telephone (804) 864-8150 | Fax: (804) 864-8155