1. Conduct testing in the following locations:
   • • Radon testing must occur in all occupied areas where the floors or walls are in direct contact with the ground or is over crawlspaces, utility tunnels or parking garages. Health Canada defines an occupied area as one that is occupied by an individual for four hours per day
     • Unoccupied rooms should also be tested at the same time as occupied rooms if there are plans for them to become occupied in the near future
     • If none of the ground contact floors are occupied, test all occupied rooms on the first occupied floor level above
2. Water utility history (at least 12 months of continuous data, typically the previous 24-36 months of data) for each energy source
3. Use only measurement devices approved by C-NRPP
4. Final analysis must be completed by a laboratory certified by the C-NRPP or similar. Not all measurement protocols require laboratory analyses (e.g., E-PERM Electrets) so long as the analyst is accredited to conduct that analysis through C-NRPP
5. The radon risk assessment report must be signed by an individual certified by the C-NRPP or similar certification body
OR 
6. If selecting no, for properties located in Canada, go to link, find the region where this building is located and enter the % of homes in that region with high radon levels: ____ %

High radon levels can potentially exist on upper floors due to the upward movement of air from stack effect or if radon is suspected to be emanating from building materials. However, Health Canada has conducted large-scale testing of federal buildings, and these factors are not considered to be significant. If elevated radon levels are identified on the lower floors, the C-NRPP mitigation professional could potentially conduct diagnostic testing on the upper floors while the mitigation strategy is being developed, to confirm the full scope of mitigation required.