IN SHORT
- Mould spores are always present outdoors. That's normal.
- An outdoor control sample shows what normal looks like for your area.
- Indoor results are compared against it to look for differences.
- Results should be interpreted by a qualified Indoor Environmental Professional.
Why the outdoor sample comes first
Every home is surrounded by airborne mould spores, which are natural and expected. An outdoor sample, called a control sample, shows the normal fungal ecology of your area at the time. The industry standard calls this normal state Condition 1.
Indoor samples are compared against that benchmark. If indoor results show types or amounts of spores that differ significantly from outside, that can point to a source inside the property.
When sampling can help
- When there's a persistent musty smell but nothing visible.
- When contamination in air conditioning or ducting is suspected.
- When an insurer or another party needs formal documentation.
- When a visual inspection can't answer the question.
What results can show
Laboratory analysis helps a professional understand whether an area is likely to be:
- Condition 2: settled spores and fragments that have spread from a growth area.
- Condition 3: actual mould growth, visible or hidden.
Interpretation matters
There are no specific Australian regulatory limits for mould in indoor air, so results need expert interpretation. A qualified Indoor Environmental Professional (IEP) looks at spore types, counts and patterns, not just raw numbers. Home test kits can produce numbers without that context, which makes them easy to misread.
WHERE DRYSAFE FITS
Our assessment is visual, with moisture and humidity readings. When there is visible mould to remove, that is where we come in.