Department of Civil and Environmental Engineering, Virginia Tech , Blacksburg, Virginia 24061, United States.
Environ Sci Technol. 2013 Nov 19;47(22):12946-51. doi: 10.1021/es402911e. Epub 2013 Nov 4.
Formaldehyde, a known human carcinogen and mucous membrane irritant, is emitted from a variety of building materials and indoor furnishings. The drive to improve building energy efficiency by decreasing ventilation rates increases the need to better understand emissions from indoor products and to identify and develop lower emitting materials. To help meet this need, formaldehyde emissions from indoor materials are typically measured using environmental chambers. However, chamber testing results are frequently inconsistent and provide little insight into the mechanisms governing emissions. This research addresses these problems by (1) developing a reference formaldehyde emissions source that can be used to validate chamber testing methods for characterization of dynamic sources of formaldehyde emissions and (2) demonstrating that emissions from finite formaldehyde sources can be predicted using a fundamental mass-transfer model. Formaldehyde mass-transfer mechanisms are elucidated, providing practical approaches for developing diffusion-controlled reference materials that mimic actual sources. The fundamental understanding of emissions mechanisms can be used to improve emissions testing and guide future risk reduction actions.
甲醛是一种已知的人类致癌物和黏膜刺激物，会从各种建筑材料和室内陈设中释放出来。通过降低通风率来提高建筑能源效率的驱动力，增加了人们对室内产品排放物的更好理解的需求，并确定和开发排放量更低的材料。为了满足这一需求，通常使用环境舱来测量室内材料的甲醛排放量。然而，舱内测试结果经常不一致，并且对控制排放的机制提供的了解甚少。本研究通过以下方式解决了这些问题：(1)开发可用于验证用于表征甲醛动态排放源的舱内测试方法的参考甲醛排放源；(2)表明可以使用基本质量传递模型来预测有限甲醛源的排放。阐明了甲醛质量传递机制，为开发模拟实际源的扩散控制参考材料提供了实用方法。对排放机制的基本理解可用于改进排放测试并指导未来的减少风险行动。
