模拟复用的医用外科口罩清洗和消毒后主要性能指标变化

目的 医用外科口罩模拟复用清洗和消毒后主要性能指标变化。方法 以颗粒过滤效率（PFE）、细菌过滤效率（BFE）作为医用外科口罩的关键性能指标,对不同佩戴时间、不同干燥方式、不同洗消方式等试验条件进行验证。结果 试验后的医用外科口罩关键性能指标能够符合标准要求。结论 医用外科口罩采用清水洗涤、56℃热水浸泡和100℃沸水浸泡处理后主要性能指标未见明显下降。     

医用外科口罩和防护口罩生物气溶胶过滤效率的评价

目的:对医用外科口罩和防护口罩的颗粒过滤效率(particle filtration efficiency,PFE)、细菌过滤效率(bacte-rial filtration efficiency,BFE)及病毒过滤效率(viral filtration efficiency,VFE)进行评价.方法:参照YY 0469...     

医用外科口罩颗粒过滤效率和细菌过滤效率的相关性研究

目的：研究医用外科口罩颗粒过滤效率和细菌过滤效率的相关性。方法：随机抽取2020年1月26日～2020年3月15日收到的注册检验样品100批次,对100批医用外科口罩的颗粒过滤效率和细菌过滤效率按照YY0469-2011的方法进行检测,并对试验结果进行比对分析。结果：本次测试的样品,若细菌过滤效率符合标准要求,颗粒过滤效率也符合标准要求;若颗粒过滤效率不符合标准,细菌过滤效率也不符合标准要求。结论：医用外科口罩颗粒过滤效率和细菌过滤效率具有一定相关性,但两者不可相互替代。     

医用外科口罩过滤效率检测

目的分析医用外科口罩常见的不合格项——过滤效率、压力差。方法参照YY0469-2011标准中规定的方法,对不同厂家生产的医用外科口罩过滤效率及压力差进行评价。结果厂家1、2、3生产的医用外科口罩符合标准要求,其他厂家生产的口罩未达标。结论选择合适的滤料是生产合格口罩的先决条件,建议生产企业选取滤料时,不但要考虑滤料的过滤效率,还应考虑其阻力性能。     

2020年和2021年新疆口罩细菌过滤效率检验结果分析

目的 分析新疆口罩细菌过滤效率检验结果,为医疗器械监管提供参考。方法 按照YY 0469—2011《医用外科口罩》附录B细菌过滤效率(BFE)试验方法进行检验,依据YY 0469—2011《医用外科口罩》和YY/T 0969—2013《一次性使用医用口罩》中“细菌过滤效率”检验项目,分别对医用外科口罩和一次性使用医用口罩进行检验,并按照标准进行判定。结果 2020年和2021年新疆口罩细菌过滤效率检验共进行469批,其中436批次为合格,总合格率为93.0%,2年的整体合格率分别为90.6%、97.1%。结论 2020年和2021年新疆口罩细菌过滤效率整体合格率结果大幅度提升,监管的力度逐渐加大,以问题为导向,对于问题产品和问题企业加大监督抽检力度,保障口罩的质量安全。     

2020年青岛市医用口罩质量评价

目的:评价2020年青岛市生产的医用口罩的过滤效率和微生物指标.方法:对37批次三种类型的医用口罩分别按照现行标准GB19083-2010《医用防护口罩技术要求》、YY 0469-2011《医用外科口罩》、YY/T 0969-2013《一次性使用医用口罩》进行检测.结果:所检批次口罩中,有两批次的微生物指标不符合规定,...     

医用口罩防护效果研讨

目的 探讨各类医用口罩的防护效果,确定使用范围,合理选用.方法 对各类医用口罩执行的技术标准进行分析,指导医务人员合理选用.结果 医用防护口罩有国家技术标准,颗粒过滤效率≥95％,决定其能阻挡经空气传播的直径＜5 μm的感染因子或近距离接触经飞沫传播的感染因子;医用外科口罩有行业技术标准,对气溶胶的过滤效率＞30％,细菌过滤效率＞95％;当体液以16.0 kPa(120 mm Hg)压力喷向口罩外侧面后,口罩内侧面无渗透;普通医用口罩仅对0.3 μ m直径的气溶胶达到20.0％～25.0％的防护效果.结论 医用防护口罩能阻止经空气或飞沫传播的大部分细菌、病毒等病原体,适用于呼吸科传染病区、发热门诊等科室;医用外科口罩可以阻隔大部分细菌和部分病毒,能阻隔血液、体液、分泌物等的喷溅,既能防止医务人员被感染,又能防止医务人员向外界传播病原菌,适用于临床医务人员的基本防护.     

医用防护口罩的重复使用性能评估

呼吸道飞沫和接触传播是呼吸系统疾病的主要传播途径。经验证,佩戴医用防护口罩可有效预防呼吸系统疾病。在应急及日常生活中常存在重复使用口罩的情况。基于此,该研究依据GB 19083-2010《医用防护口罩技术要求》对医用防护口罩进行模拟使用、消杀,并检测处理前后过滤效率、气流阻力性能及纤维微观结构,以评估重复使用性能。经检验,医用防护口罩经佩戴、紫外线照射和沸水浸煮前后的物理性能及内部纤维微观结构无明显变化,可重复使用。75%乙醇喷淋会导致医用防护口罩过滤效率下降,影响重复使用性能。     

医用口罩的正确选择与使用

目的探讨各种医用口罩的防护效果、适用范围和正确的使用方法。方法通过分析各类口罩的技术标准,了解各种医用口罩的防护效果,从而指导医务人员在临床工作中如何正确选择和使用医用口罩。结果医用外科口罩和医用防护口罩有国家技术标准,能起到有效阻挡病原体的防护作用,其他类型口罩没有统一的技术标准,仅有一定的机械阻挡作用,不能有效阻挡病原体通过呼吸道入侵。结论医师在临床工作中应根据实际情况和防护目的,正确选择与使用医用口罩,以达到防止呼吸道传播的感染性疾病和传染病在医院内的传播,做好有效的职业防护,减少医院感染的发生。     

在售医用口罩关键参数的检测与分析

目的：根据相关国家和行业标准,对已上市的一次性医用防护口罩、一次性医用外科口罩和一次性医用口罩进行相关检测分析,评价市面上口罩的整体质量,为上市后监管提供参考。方法：按照YY/T 0969-2013《一次性使用医用口罩》、YY 0469-2011《医用外科口罩》和GB 19083-2017《医用防护口罩技术要求》,对口罩关键参数如口罩带、过滤效率、气流阻力、合成血液穿透阻力和环氧乙烷残留量等进行检测。结果：随机抽取的69批产品中有9批不合格。结论：抽取的在售口罩有超过10%的产品检测不符合相应的标准。     

中国和欧盟医用外科口罩细菌检测方法对回收率的影响

 目的 明确我国和欧盟医用外科口罩细菌检测方法回收率的差异。方法 采用微生物回收的方法对中国《医用外科口罩(YY 0469-2011)》和欧盟《医用口罩要求和试验方法(EN 14683-2019)》中的检测方法回收率进行对比分析,并探索两种方法中最优方法的环节。结果 EN 14683-2019检测方法回收率高达65.1%,高于YY 0469-2011标准近4倍;洗脱方式为机械振摇,洗脱效果不如手动振摇法(回收率为68.6%);EN 14683-2019的可接受标准严于YY 0469-2011的可接受标准。结论 EN 14683-2019的洗脱液中含有表面活性成分(吐温20),提高了检测方法的回收率;YY 0469-2011方法中手动振摇的洗脱方式对微生物的洗脱效果要优于EN 14683-2019方法中的机械振摇法。     

我国非医用口罩标准及防护性能介绍

 

新型冠状病毒肺炎（COVID-19）主要通过近距离飞沫传播和接触传播,口罩可以降低感染风险和传播概率,但因医用口罩产能有限,各地政府鼓励企业生产非医用口罩,以满足公众新冠肺炎疫情防控需要。本文介绍我国非医用口罩相关标准,对比分析其细菌过滤效率、颗粒物过滤效率等防护性能要求,提出非医用口罩防护新型冠状病毒的重要指标。同时,分析2020年1月27日-2月25日我国各省公示的102份非医用口罩企业标准,提出疫情防控非医用口罩标准化的建议,以期为相关部门、生产企业及普通人群提供帮助。

     

不同种类口罩防血液穿透性能研究

 目的 探究不同种类口罩防血液穿透性能的差异,研究口罩形状对血液穿透的影响,评估口罩的防血液穿透性能。 方法 选择三种类型口罩:医用防护口罩(折叠式)、KN95口罩(拱形)、一次性医用外科口罩(平面),对口罩表面拒水层进行测试,通过高速摄影分析血液喷射与流动的形态轨迹,计算不同条件(压力、距离、时间)下口罩表面血液面积。 结果 口罩表面均具有疏水性(接触角>130°)。标准条件下(120 mmHg,30 cm),医用防护口罩(折叠式)、KN95口罩(拱形)、一次性医用外科口罩(平面)血液附着面积分别为1.79、2.53、4.72 cm²;高压条件下(160 mmHg,30 cm),血液附着面积均上升;短距离条件下(120 mmHg,15 cm), 医用防护口罩(折叠式)、KN95口罩(拱形)表面血液面积减少,一次性医用外科口罩(平面)血液面积变大;长时间的高压喷射下(60 s,160 mmHg), KN95口罩(拱形)内层出现血液穿透现象。 结论 三种口罩合成血液穿透性能均达到国内外最高等级标准。KN95口罩(拱形)排液能力与阻隔性能表现最优,其次为医用防护口罩(折叠式),但在极限条件下KN95口罩(拱形)因出现血液渗透而失效。     

In vivo protective performance of N95 respirator and surgical facemask

BACKGROUND: The SARS outbreak in 2003 has spawned a major controversy concerning protective performance facemasks for healthcare workers. This study reports a study on in-vivo protective performance of surgical masks and N95 respirators. METHODS: Typical surgical masks and N95 respirators used in Hong Kong hospitals were tested in comparison with those treated with nano-functional materials (called nano-masks) on various physical properties and in-vivo wear filtration efficiency, as well as usability test in hospitals for surgical masks. RESULTS: Tests on physical properties showed that N95 respirators had significantly lower air permeability and water vapor permeability than surgical masks. The in-vivo filtration tests illustrated that N95 respirators filtered out 97% of potassium chloride (KCl) solution, while surgical masks filtered out 95% of KCl solution. Nano-masks show stronger water repellency and antibacterial activities, but no difference in usability, comparing with normal N95 and surgical masks. CONCLUSIONS: Surgical masks can provide in-vivo filtration protection of 95% filtration efficiency. N95 respirators provide higher in-vivo filtration efficiency of 97% with significant reduction of air permeability and water vapor permeability. Compared to normal surgical masks/respirators, the nano-masks can provide additional protective functions in stopping capillary diffusion and antibacterial activities.     

A comparison of facemask and respirator filtration test methods

NIOSH published a Federal Register Notice to explore the possibility of incorporating FDA required filtration tests for surgical masks (SMs) in the 42 CFR Part 84 respirator certification process. There have been no published studies comparing the filtration efficiency test methods used for NIOSH certification of N95 filtering facepiece respirators (N95 FFRs) with those used by the FDA for clearance of SMs. To address this issue, filtration efficiencies of “N95 FFRs” including six N95 FFR models and three surgical N95 FFR models, and three SM models were measured using the NIOSH NaCl aerosol test method, and FDA required particulate filtration efficiency (PFE) and bacterial filtration efficiency (BFE) methods, and viral filtration efficiency (VFE) method. Five samples of each model were tested using each method. Both PFE and BFE tests were done using unneutralized particles as per FDA guidance document. PFE was measured using 0.1 µm size polystyrene latex particles and BFE with ～3.0 µm size particles containing Staphylococcus aureus bacteria. VFE was obtained using ～3.0 µm size particles containing phiX 174 as the challenge virus and Escherichia coli as the host. Results showed that the efficiencies measured by the NIOSH NaCl method for “N95 FFRs” were from 98.15–99.68% compared to 99.74–99.99% for PFE, 99.62–99.9% for BFE, and 99.8–99.9% for VFE methods. Efficiencies by the NIOSH NaCl method were significantly (p = <0.05) lower than the other methods. SMs showed lower efficiencies (54.72–88.40%) than “N95 FFRs” measured by the NIOSH NaCl method, while PFE, BFE, and VFE methods produced no significant difference. The above results show that the NIOSH NaCl method is relatively conservative and is able to identify poorly performing filtration devices. The higher efficiencies obtained using PFE, BFE and VFE methods show that adding these supplemental particle penetration methods will not improve respirator certification.     

Quantification of leakage of sub-micron aerosols through surgical masks and facemasks for pediatric use

Surgical respirators, surgical masks (SMs), and facemasks for pediatric use (FPUs) are routinely used in the U.S. healthcare industry as personal protective equipment (PPE) against infectious diseases. While N95s including surgical respirators have been routinely studied, SMs and FPUs have not received as much attention, particularly in the context of aerosolized threats. This is because SMs and PFUs are not designed to protect against sub-micron aerosols. However, with the possibility of new or re-emerging airborne diseases or bio-aerosol weapons lingering, combined with the limited availability of respirators and logistical issues associated with fit-testing millions, the general adult and pediatric populations may elect to wear SMs and FPUs, respectively, in the case of a pandemic or a bio-terrorist attack. When a person dons a PPE, gaps are created between the wearer's face and the PPE, and aerosols leaking through these gaps can be an important contributor to the risk of infection compared to filtered aerosols. To understand and quantify the contribution of leakage of aerosols through gaps, with particular emphasis on SMs and FPUs, this study investigated leakage of charge-neutralized, polydispersed, dried sodium-chloride aerosols across different brands of PPE. Different breathing rates, aerosol particle sizes, and gap sizes were considered. A few major findings of this study were: (a) leakage, is not a strong function of sub-micron aerosol size; (b) for the same gap size, leakage of aerosols through surgical respirators can often be higher than in SMs and FPUs; and (c) as the gap size increases, the increase in leakage through surgical respirators is higher compared for SMs and FPUs, implying that some SMs and FPUs that possess electret layers may be preferable to N95s that have not been fit-tested. The results obtained can also be used to explain conflicting findings from clinical studies on the effectiveness of SMs when compared to N95s and can be input into risk-assessment models to determine the increase in infection rate resulting from deployment of PPE under less-than-ideal conditions.     

滤膜法与涂抹法检测内镜清洗消毒效果及成本比较

目的对比分析滤膜法与涂抹法检测内镜清洗消毒的效果及成本。方法随机抽取某大型三甲综合医院2018年1—12月清洗消毒后内镜,同一内镜分别采用滤膜法和涂抹法检测内镜清洗消毒效果。比较两种方法检测的合格率、病原菌检出率、菌落计数及成本消耗。并利用问卷星与微信平台调查部分医院内镜清洗消毒效果检测方法现状。结果共检测软式内镜207支。滤膜法与涂抹法的检测合格率分别为78.26%、95.65%,差异有统计学意义(P0.001)。内镜清洗消毒后病原菌检出率、检出菌落数滤膜法均高于涂抹法,差异有统计学意义(P0.001)。207支内镜滤膜法较涂抹法每年增加经济成本1 498.48元,平均每支增加7.24元/次。使用滤膜法较涂抹法平均每支内镜多耗时62 s。共调查26所医院的内镜清洗消毒后检测方法使用情况,仅有2所医院使用滤膜法。对于使用滤膜法检测内镜清洗消毒效果,医院最关注的问题为增加的经济成本。结论检测内镜清洗消毒效果时,滤膜法可以更有效的培养出内镜洗脱液中的细菌,客观的反映内镜清洗消毒效果。