This study analyzes the growth and reproduction of dust accumulated fungi (DAF) in an air-conditioning system based on field measurement and molecular biology, laboratory experiment and prediction modelling. The field measurement was conducted to collect dust in filter screen, surface cooler and air supply duct of two air handling units (AHUs). The results indicate that dust volume and fungal number in two AHUs generally met the hygienic specification of public buildings, but the cleansing did not fulfil requirements. High-throughput sequencing was conducted, revealing that the dominant fungal species were Alternaria_betae-kenyensis, Cladosporium_delicatulum, Aspergillus_sydowii, Verticillium_dahliae. Laboratory experiment was conducted to analyze the impact of several factors (e.g. growth time, temperature, relative humidity, duct material) and their combination on the DAF growth. The results indicate that fungal growth increased with time, peaking at 4 days or 5 days. Higher relative humidity or temperature was conducive to fungal growth. The orthogonal experiment revealed that the condition of “antibacterial composite, 22 ± 1 °C and 45%–55% RH” had the strongest inhibiting impact on fungal growth. Logistic model, Gompertz model and square-root model were further developed to predict the fungal growth under different conditions. The results show that the Logistic model had high feasibility and accuracy, the Gompertz model was feasible with lower accuracy and the square-root model was feasible with high accuracy. Overall, this study facilitates the understanding of the DAF growth in air-conditioning ducts, which is important for real-time prediction and timely control of the fungal contamination.

本研究基于现场测量和分子生物学、实验室实验和预测模型，分析了空调系统中积尘真菌 (DAF) 的生长和繁殖情况。进行现场测量以收集两个空气处理单元（AHU）的滤网、表面冷却器和送风管道中的灰尘。结果表明，两台空气处理机组的粉尘量和真菌数量总体上符合公共建筑卫生规范，但清洁不符合要求。进行了高通量测序，揭示了优势真菌物种是链格孢属_betae-kenyensis、Cladosporium_delicatulum、Aspergillus_sydowii、Verticillium_dahliae. 进行了实验室实验，分析了几个因素（如生长时间、温度、相对湿度、管道材料）及其组合对 DAF 生长的影响。结果表明，真菌生长随时间增加，在 4 天或 5 天达到峰值。较高的相对湿度或温度有利于真菌的生长。正交实验表明，“抗菌复合、22±1℃、45%~55%RH”条件对真菌生长的抑制作用最强。进一步发展了Logistic模型、Gompertz模型和平方根模型来预测不同条件下的真菌生长。结果表明，Logistic模型具有较高的可行性和准确性，Gompertz模型具有较低的准确性，而平方根模型具有较高的准确性。全面的，