How to Remove a Mould Smell – with Ozone, Done Properly
Ozongenerator.Nu – Editorial team · Updated 2026-06-22
A musty, damp mould odour comes from moisture and microbial activity. An ozone treatment breaks the smell molecules down rather than masking them – but it is not a substitute for fixing the problem: remove visible mould and sort out the moisture source first, otherwise the smell will simply return.
Why the smell is not the same as the cause
A mould smell is a symptom of moisture. Ozone reliably removes the odour – but only for good once the moisture (a leak, poor ventilation, condensation) has been dealt with.
How to go about it
1) Remove visible mould mechanically. 2) Fix the moisture source and dry the area thoroughly. 3) Treat the empty, closed room with ozone for 60–120 minutes. 4) Air it out for at least 30 minutes. No people, pets or plants may be in the room during the treatment.
Which machine for which area
For single rooms or cupboards an Oxia Compact (up to 30 m²) is plenty. For a basement, a flat or larger areas the Oxia Plus (up to 100 m²) is the right choice, and for professional remediation the Oxia Pro.
Frequently asked questions
Does ozone get rid of mould?
Ozone removes the mould SMELL by breaking the odour molecules down. Visible mould you must remove mechanically, and the moisture must be fixed.
Will the smell come back?
Only if the moisture source remains. Fix the underlying cause and the room stays odour-free.
How long does a treatment take?
60–120 minutes depending on room size, followed by at least 30 minutes of airing out.
Sources & authorities
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