The cheapest kits are short-term charcoal canisters, which Mississippi's health department puts at about $10 to $15 in stores; an alpha track detector, the usual , is about $30 there. Washington's health department calls do-it-yourself kits easy to use and inexpensive, at about $20.
Some states sell their own kits or give them away. New York's Department of Health sells one for $12.25 with the analysis and postage included, and Virginia's offers a limited supply of short-term kits for only a $4 shipping fee. Check whether a store kit's price includes the laboratory fee and return postage: often it does, but not always.
A professional test costs more because a qualified tester places the device and reports the result, often with a continuous monitor; Michigan puts a continuous monitor test at around $75 to $200. Passive devices are generally inexpensive, while active devices with anti-interference features may cost more but may give a more reliable result.