For most Canadian homeowners, a one-time test is enough unless something changes — new symptoms, a renovation, a flood or pipe burst, a new pet, or a real estate transaction. Health Canada recommends every home test for radon at least once (radon levels can change over years), and any home with a history of moisture issues should re-test for mold spores annually until the source is fully resolved.

The on-site visit takes 60–90 minutes for a typical Canadian home (longer for multi-storey or commercial buildings). Samples ship to the lab the same day. Most contaminant panels return results in 3–5 business days; rush turnaround is usually available for an additional fee. You receive a written report with raw lab data, a plain-English interpretation, and recommended next steps.

The most common signs reported in Health Canada’s IAQ guidance are headaches, fatigue, irritated eyes/nose/throat, congestion, worsening asthma or allergy symptoms indoors that improve when you leave the house, persistent musty or chemical odours, visible mold growth, and recurring condensation on windows. If symptoms cluster around a specific room or worsen seasonally, that room is the place to start sampling.