• The results of previous testing;
  
  
• Who conducted the previous test: the homeowner, a radon professional, or some other person;
  
  
• Where in the home the previous test was taken, especially if you may plan to live in a lower level of the home. For example, the test may have been taken on the first floor. However, if you want to use the basement as living space, test there; and
  
  
• What, if any, structural changes, alterations, or changes in the heating, ventilation, and air conditioning (HVAC) system have been made to the house since the test was done. Such changes may affect radon levels.

If you accept the seller's test, make sure that the test followed the Radon Testing Checklist.

If you decide that a new test is needed, discuss it with the seller as soon as possible. If you decide to use a qualified radon tester, contact your state radon office to obtain a copy of their approved list of radon testing companies.

If the home has not yet been tested for radon - Make sure that a radon test is done as soon as possible. Consider including provisions in the contract specifying:

• Where the test will be located;
  
  
• Who should conduct the test;
  
  
• What type of test to do;
  
  
• When to do the test;
  
  
• How the seller and the buyer will share the test results and test costs (if necessary); and
  
  
• When radon mitigation measures will be taken and who will pay for them.

Make sure that the test is done in the lowest level of the home suitable for occupancy. This means the lowest level that you are going to use as living space which is finished or does not require renovations prior to use. A state or local radon official or qualified radon tester can help you make some of these decisions.