Simplified Estimation of Indoor Air Quality Based on Material Pollutant Emission Rates and Concentration Responses

• • Environmental chamber tests on 34 material categories (25 solid, 9 liquid) reveal that both formaldehyde and TVOC concentrations peak on day 2 post-decoration, but liquid materials decay by 70%–90% within one week, whereas solid materials decay slower, becoming the dominant long-term source. • • The simplified estimation method, validated against multi-material composite scenarios, yields acceptable errors and enables rapid air quality prediction within 2–3 hours, compared to weeks for chamber testing and complex model calculations. • • Material emission rates are classified into four grades (F1–F4) for formaldehyde (thresholds: <0.01, 0.01–0.03, 0.03–0.06, 0.06–0.12 mg·(m²·h)−1) and TVOC (thresholds: <0.04, 0.04–0.20, 0.20–0.40, 0.40–0.80 mg·(m²·h)−1), enabling standardized risk screening. • • The method addresses the disconnect between single-material compliance and whole-room exceedance ('single product qualified, overall exceedance') by incorporating area loading rates and ventilation, thus supporting proactive source control in design phases.