Mold Growth Conditions

Risk by temperature, RH, and time.

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Details, formula, and sources

(reference page; no compute) Mold-growth conditions: temperature 40-100 °F, RH ≥ 60-70% sustained, organic substrate, time ≥ 24-48 hours. EPA / IICRC S520-2024 thresholds.

EPA 402-K-01-001 (Mold Remediation in Schools and Commercial Buildings) + IICRC S520-2024 (Standard for Professional Mold Remediation) by name.

EPA 402-K-01-001 free at epa.gov/mold. IICRC S520-2024 licensed.

Estimate. AHJ and licensed professional govern.

Field names used by the API: rh_percent, temperature_F, hours_elevated, risk, threshold_rh_growth_percent, threshold_rh_high_percent, typical_germination_hours

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