There are some radon dangers most have not thought of.  While most houses in RI are tested for radon in the air, few are tested for radon in the water.  Radon can be a danger in water if the water comes from a well or a public supply that uses a well.  Both radon in the air and water are pretty easy to cure.  Radon in the air is usually cured by a vent pipe system with fan, which pulls radon from beneath the house and vents it outside.  Water radon can be cured by a system installed just before the waters enters the home.  Here is the link to the EPA report:

 http://www.epa.gov/radon/pubs/citguide.html

Another danger just recently discussed is from granite counters.  I never thought of this, but now that it has come to my attention, it makes sense.  Since granite is natural rock, it could contain uranium which is what produces radon gas.  This is the quote from the EPA, "At this time, however, EPA does not believe sufficient data exist to conclude that the types of granite commonly used in counter tops are significantly increasing indoor radon levels".  Here is a link to their report on this:

http://iaq.custhelp.com/cgi-bin/iaq.cfg/php/enduser/std_adp.php?p_faqid=5103&p_created=1212758208&p_sid=qQmTaU9j&p_accessibility=0&p_redirect=&p_lva=&p_sp=cF9zcmNoPSZwX3NvcnRfYnk9JnBfZ3JpZHNvcnQ9JnBfcm93X2NudD0yMSwyMSZwX3Byb2RzPTM3MCZwX2NhdHM9JnBfcHY9MS4zNzAmcF9jdj0mcF9zZWFyY2hfdHlwZT1hbnN3ZXJzLnNlYXJjaF9ubCZwX3BhZ2U9MQ**&p_li=&p_topview=1

 So, the best advice is test, test, test.  Either hire a professional to test or purchase your own kit.  Don't take it for GRANITE:-)