生物安全实验室通风系统HEPA过滤器原位消毒及检漏方案

结合我国高等级生物安全实验室建设的现状及相关标准要求,介绍了HEPA过滤器扫描检漏法、效率检漏法及气体消毒法,探讨了室外箱式HEPA过滤器单元、室内HEPA过滤器单元及风口型HEPA过滤器单元的原位消毒及检漏技术方案.     

公共建筑PM2.5空气净化应用探讨

大型公共建筑PM2.5控制技术是指室内外新回风通过物理过滤技术手段进行PM2.5高效过滤,为室内环境提供安全、健康、舒适、节能的空气.PM2.5过滤成套装置包括PM2.5空气过滤器、PM25浓度探测仪、PM2.5浓度显示仪等产品.     

两架民用航空器高效空气过滤器滤网微生物的菌属鉴定分析

目的初步了解我国民用航空器座舱高效空气过滤器(HEPA)滤网微生物污染状况。方法采用涂抹法对高效空气过滤器再循环风扇滤网进风口面和出风口面采样。2015年11月及2016年1月,分别收集2架波音客机高效空气过滤器滤网,共采集细菌样本48个,真菌样本75个,通过分子生物技术对样本种属进行鉴定。结果对飞机高效过滤器滤网表面的进风口表面和出风口表面的细菌总数和真菌总数,以及两架不同机龄的飞机再循环风扇滤网表面的细菌总数、真菌总数分别进行了比较,发现差异均存在统计学意义(P<0.05)。同时,进风口表面细菌优势菌种鉴定可能为杆菌属、真菌优势菌种为枝孢属、曲霉菌属、球腔菌属、小光壳属、青霉菌属。结论滤网出风口面较进风口面卫生,推断高效空气过滤器对细菌、真菌的过滤效果良好,下一步飞机消毒方式应重点针对飞机座舱内座椅、配餐间、卫生间等的物表消毒,其次是空气消毒。     

通风空调系统中紫外线辐射消毒的应用

介绍了紫外线消毒技术的应用情况,分析了紫外线辐射消毒在通风空调系统中应用的可行性,认为紫外线消毒装置与空气过滤器组合使用才能发挥出更大的效应,在通风空调系统中宜将紫外线消毒装置设置在空气处理机组内盘管的出口侧。     

生物安全实验室排风高效过滤器检漏方法探讨

介绍了生物安全实验室的安全防护及排风系统的重要性。对《生物安全实验室建筑技术规范》GB50346-2004中有关排风高效过滤器检漏试验的可行性进行了分析讨论,提出在实验室适当位置设置排风高效过滤装置专用检漏接口的建议。强调对厂检合格的排风高效过滤装置在安装前也应在现场进行再检漏,以防止由于装御、运输造成的泄漏。     

公共建筑PM_(2.5)空气净化应用探讨

大型公共建筑PM2.5控制技术是指室内外新回风通过物理过滤技术手段进行PM2.5高效过滤,为室内环境提供安全、健康、舒适、节能的空气。PM2.5过滤成套装置包括PM2.5空气过滤器、PM2.5浓度探测仪、PM2.5浓度显示仪等产品。     

空气过滤器

空气过滤器属于过滤集尘装置的一种,它和表1所列举的袋式过滤器不同。从集尘机构来讲,袋式过滤器是通过充填率较高的布和粉尘层进行过滤,而空气过滤器由于采用充填率低于10％的纤维状过滤材料,因此在集尘装置中空气过滤器从理论分析方面发展极为迅速。随着原子能和洁净室的需要,空气过滤器的性能正在日益提高。表2是说明纸过滤器的滤纸特性,后三种是高效滤纸。     

关于GB13554—92标准中高效空气过滤器的分类

空气过滤器是过滤空气中悬浮粒子的设备。《高效空气过滤器 GB13554-92(简称高效过滤器)是指按国际规定的方法检验,其效率达到99.9％以上的过滤器。当对≥0.1μm的粒子计数效率达到99.99％以上时,亦称超高效过滤器。高效过滤器是实现高洁净度空气净化的关     

高等级生物安全实验室气密性装置气体消毒过程中压力变化趋势及对策

为了研究高等级生物安全实验室气密性装置气体消毒过程中的压力变化趋势,以ABSL-3中一个总管排风高效过滤器单元为研究对象,选取2种消毒设备,设置4种消毒程序,实时监测消毒过程中高效过滤器单元的压力和温度变化,定性分析压差变化的原因。研究结果表明:消毒过程中不控制压力时,高效过滤器单元内会出现较大的正压差;消毒过程中控制压力时,高效过滤器单元内压差比较稳定。提出了气密性装置消毒过程中的压力控制策略,以控制生物安全风险。     

空气过滤技术及应用

主要阐述了空气中微粒污染物的来源及其对人体的危害,分析了针对含有微粒的各种空气过滤技术的原理及优缺点,同时根据过滤材料的研究进展、空气过滤器的原理及其研究进展、空气过滤技术的应用等方面的内容指出了空气过滤技术发展趋势。     

洁净室高效空气过滤器现场检漏方法的实验研究——国标《洁净室施工及验收规范》编制组研讨系列课题之七

高效空气过滤器现场扫描检漏测试是保证洁净室工程质量的必要措施之一,但在实际工程测试时常遇到将高效空气过滤器边框及安装框架处含尘浓度偏高误判为存在漏点的问题,介绍了IEST给出的相关测试方法及部分洁净室施工人员采取的非扫描检漏测试方法,通过理论分析及大量实验研究,提出了科学合理的高效空气过滤器扫描检漏测试方法。     

Combined use of an electrostatic precipitator and a high‐efficiency particulate air filter in building ventilation systems: Effects on cardiorespiratory health indicators in healthy adults

High‐efficiency particulate air (HEPA) filtration in combination with an electrostatic precipitator (ESP) can be a cost‐effective approach to reducing indoor particulate exposure, but ESPs produce ozone. The health effect of combined ESP‐HEPA filtration has not been examined. We conducted an intervention study in 89 volunteers. At baseline, the air‐handling units of offices and residences for all subjects were comprised of coarse, ESP, and HEPA filtration. During the 5‐week long intervention, the subjects were split into 2 groups, 1 with just the ESP removed and the other with both the ESP and HEPA removed. Each subject was measured for cardiopulmonary risk indicators once at baseline, twice during the intervention, and once 2 weeks after baseline conditions were restored. Measured indoor and outdoor PM_2.5 and ozone concentrations, coupled with time‐activity data, were used to calculate exposures. Removal of HEPA filters increased 24‐hour mean PM_2.5 exposure by 38 (95% CI: 31, 45) μg/m³. Removal of ESPs decreased 24‐hour mean ozone exposure by 2.2 (2.0, 2.5) ppb. No biomarkers were significantly associated with HEPA filter removal. In contrast, ESP removal was associated with a ?16.1% (?21.5%, ?10.4%) change in plasma‐soluble P‐selectin and a ?3.0% (?5.1%, ?0.8%) change in systolic blood pressure, suggesting reduced cardiovascular risks.     

Bacterial communities in commercial aircraft high‐efficiency particulate air (HEPA) filters assessed by PhyloChip analysis

Abstract  Air travel can rapidly transport infectious diseases globally. To facilitate the design of biosensors for infectious organisms in commercial aircraft, we characterized bacterial diversity in aircraft air. Samples from 61 aircraft high‐efficiency particulate air (HEPA) filters were analyzed with a custom microarray of 16S rRNA gene sequences (PhyloChip), representing bacterial lineages. A total of 606 subfamilies from 41 phyla were detected. The most abundant bacterial subfamilies included bacteria associated with humans, especially skin, gastrointestinal and respiratory tracts, and with water and soil habitats. Operational taxonomic units that contain important human pathogens as well as their close, more benign relatives were detected. When compared to 43 samples of urban outdoor air, aircraft samples differed in composition, with higher relative abundance of Firmicutes and Gammaproteobacteria lineages in aircraft samples, and higher relative abundance of Actinobacteria and Betaproteobacteria lineages in outdoor air samples. In addition, aircraft and outdoor air samples differed in the incidence of taxa containing human pathogens. Overall, these results demonstrate that HEPA filter samples can be used to deeply characterize bacterial diversity in aircraft air and suggest that the presence of close relatives of certain pathogens must be taken into account in probe design for aircraft biosensors.

Practical Implications

A biosensor that could be deployed in commercial aircraft would be required to function at an extremely low false alarm rate, making an understanding of microbial background important. This study reveals a diverse bacterial background present on aircraft, including bacteria closely related to pathogens of public health concern. Furthermore, this aircraft background is different from outdoor air, suggesting different probes may be needed to detect airborne contaminants to achieve minimal false alarm rates. This study also indicates that aircraft HEPA filters could be used with other molecular techniques to further characterize background bacteria and in investigations in the wake of a disease outbreak.

     

高等级生物安全实验室通风空调系统冗余设计原则探讨

对比分析了国内外标准有关高等级生物安全实验室通风空调系统冗余设计的要求。结合我国已有高等级生物安全实验室,重点分析了送风机、排风机、排风高效过滤器冗余设计的具体实施形式和存在的问题,给出了冗余设计原则建议。     

隔离病房回风高效过滤器滤菌效率的实验研究

介绍了国外各类高效过滤器的滤菌效率。在安装有高效过滤器的隔离病房回风口进行了发菌实验,计算了B类和C类回风高效过滤器的滤菌效率,证明了当隔离病房回风口安装高效过滤器时,可使用部分循环风。     

多管式高效空气过滤器的设计优化

在实验研究确立的多管式高效空气过滤器阻力的理论公式的基础上,以寿命期总费用为目标函数建立了该型过滤器的最优设计数学模型。采用序列二次规划法求解此约束优化模型,得到了该种过滤器在寿命期总费用最小时的最优化结构设计参数。并与按阻力最小化得到的结果进行了比较分析,指出基于寿命期总费用的最优设计更合理。     

In-situ effectiveness of residential HVAC filters

In this study, we explore different filter and contextual characteristics that influence effectiveness of high-efficiency filters in 21 residences in Toronto, Canada. The in situ effectiveness was assessed with decay tests at the beginning and the end of filter life with four different filters (MERV 8-14 from ASHRAE Standard 52.2) installed in operational HVAC systems, compared with either the system off or with no filter installed. There was considerable difference between median PM_2.5 effectiveness of the non-electret filters when compared to electret filters (16% vs. 36%) of the same nominal efficiency (MERV 8). However, median PM_2.5 effectiveness of electret filters only slightly improved (between 5% and 9% absolute increase) as MERV increased from 8 to 14. There was more variation in filter effectiveness between the same filter in different homes than there was between different filters in the same home. Variations in filter performance arose because home-specific particle loss rates (eg, ventilation rate) vary greatly in different buildings. The higher the loss rates due to non-filter factors, the lower the effectiveness of a filter. Given the relatively large variation in effectiveness for a given filter over time and in different homes, increasing system runtime may be a productive way to improve filter performance in many homes.     

气溶胶粒径计数法检测空气过滤器效率的探讨

介绍了国内现行空气过滤器效率的标准检测方法——大气尘计数法,指出了该效率检测方法的优缺点。详细介绍了当前欧、美等国家空气过滤器效率的标准检测方法—气溶胶粒径计数法,并从试验用气溶胶、检测仪器和效率标识三个方面对欧、美的效率检测方法进行了详细的分析比较。列出了气溶胶粒径计数法较大气尘计数法的优越性,进而提出了用气溶胶粒径计数法来检测空气过滤器效率的观点。并详细说明了用气溶胶粒径计数法检测空气过滤器效率的操作方法。     

舒适性空调空气过滤器效率计算方法

给出了舒适性空调空气过滤器效率的设计计算公式,分析了公式中各量的取值范围,以商场和办公室为例计算出了空气过滤器效率,并分析了计算结果。     

高效过滤器现场大气尘检漏方法的理论探讨——国标《洁净室施工及验收规范》编制组系列探讨问题之九

用射流理论具体论证了大气尘粒子计数器检漏方法(简称漏孔法),普通高效过滤器需要不低于2200粒/L(2.83L/min采样)的上游大气尘浓度,超高效过滤器需要不低于5800粒/L(28.3L/min采样)的上游大气尘浓度。只要扫描特征读数≥1,即可作静止检漏,若再≥3,即可判断为漏。漏孔法比ISO透过率法适用漏孔更小。