Stanley, the guidelines for the radon tests I'm familar with are:
1. Check expected weather for the time period during which you plan to test. If severe weather and/or high winds are predicted, delay starting the test until milder weather is expected.
2. Close ALL windows and exterior doors 12 hours before the start of the test and keep them closed for the entire test period. Opening and closing of exterior doors must be restricted to normal entry and exit. Do not use any internal-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 operational and on their normal settings (Auto mode, between 64 and 78 degrees): fireplaces or fireplace inserts can be operated only if they are the principal means of heating the building. No fans may be operating in the test room/area during the entire test period.
Canisters must be at least 20 to 30 inches above the floor. Canisters should be located away from all windows, doors, air ducts, air returns, stairwells and fireplaces. Fireplace flues must be closed unless the fireplace is needed to heat the building during the test. Place canisters at least one foot away from an interior wall or at least three feet away from an exterior wall.
Canisters should be left undisturbed for at least 3 and no more than 6 days. At the end of the test, reseal the canisters by firmly pressing the silver foil back over the hole in the lid of the canisters. Canisters must be received at the lab within 8 days after the completion of the test.
Canisters should be placed in the lowest-level liveable or occupiable space except: no kitchens, bathrooms, closets, laundry rooms, fireplace mantels, hallways, stairwells, storage rooms, utility rooms, attics, entrance foyers, elevators, mechanical rooms, equipment rooms, rooms with exposed dirt, and no crawlspaces.
The person placing the canisters must state that all the above guidelines have been met, otherwise the test is considered invalid.
The guidelines you received are good ones. I would add to seal around any projections coming through the exterior walls or through the floor (water pipes, sewer pipes, drain pipes, etc). If the radon test comes back above the EPA guideline of greater than 4.0 pCi/l (picoCuries of radon per liter of air) you will be advised to do these things then take another test. If the 2nd test comes in above the EPA guidelines, more extensive corrections will be necessary.
These guidelines are for using 2 activated charcoal canisters for the test. There are other ways to test for radon, but I'm not familar with them.
This link will show you a picture of the USA, along with which areas have more potential for radon problems:
http://usinspect.com/Radon/mapgeo.asp
I tried to attach this but it was too large.
You can get more information from here:
Http://usinspect.com/Radon/radon.asp
as well as a bunch of other places.
Bob