Some test kits charge an extra fee ($10-15) for quicker processing! Obtaining your results may also take up to three or four weeks depending on how busy the lab is!
Some test kits, especially those available on the Internet or at big box stores, may require you send the test to a US-based lab, thereby necessitating extra declaration paperwork and a US Customs inspection which can slow down the process significantly. Some big box test kits may be forwarded to an Ontario address (Woodbridge, or Vaughn ON) which then sends them to a Ft. Lauderdale lab. Again this takes time, usually 3-4 weeks!
Also, short-term test kits or radon instrument must also be appropriately placed in the home under strict "closed-house" test conditions. Test kits can vary in the details they include in this setup. This is not necessary for LT tests.
Also be wary of the "Real Estate" liquid scintillation-charcoal 2-day test kits sold at big box and hardware stores. They have the same caveats that are mentioned above. If you need a real estate transaction measurement, it is better to call me to do one. A 2-day test is so influenced by many factors and as a result, a reading can be highly suspect. Some charcoal-based canister test kits (without diffusion barriers) are prone to humidity and should not be used when the humidity gets above 80%. These test kits can absorb moisture thereby giving inaccurate values. Average annual morning humidity for London, ON is 86%. (Environment Canada 2010 data)
My Accustar AT-100 Long-Term Test Kits do not have this limitation.