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Mold & Surface Cleaning Calculator
The right concentration for mold removal, mildew treatment, grout cleaning, and hard surface disinfection.
Your starting product concentration
Surface / mold application
Your Result
Hydrogen peroxide to add—
Water to add—
Total solution—
Spray onto surface, dwell 10–30 min, scrub, then wipe clean. Ventilate the room during application.
Mold Treatment Reference
| Application | Target % | Dwell time | Risk |
|---|---|---|---|
| Mildew prevention spray | 1.5% | 5 min, no rinse | Low |
| Surface mold (walls, tile) | 3% | 10–15 min, wipe | Medium |
| Grout & caulk mold | 6% | 20–30 min, scrub | Medium |
| Heavy black mold (non-porous) | 6% | 30+ min, scrub & rinse | High — ventilate |
Safety Notes
- Open windows and ventilate well when treating mold.
- Wear gloves and eye protection for concentrations above 3%.
- Do not use on natural stone, marble, or unsealed wood.
- For black mold beyond 10 sq ft, consult a professional.
- Never mix with bleach or ammonia-based cleaners.
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