防护服的阻隔性能：一旦确定了暴露的危害和风险，就可以根据当前对防护服材料如何保护血液和体液中的微生物的科学认识来选择防护服。微生物在防护服材料中取决于以下几个因素：
    1.织物的物理和化学特性：包括厚度、孔径和拒水性等因素
    2.微生物的形状、大小和其他特征：包括形态、运动性和对极端环境的适应等因素
    3.载体特性：包括表面张力、体积和粘度等因素
    4.外部因素：包括物理、化学和热应力等因素
    Barrier performance of protective clothing: once the hazards and risks of exposure are determined, protective clothing can be selected according to the current scientific understanding of how protective clothing materials protect microorganisms in blood and body fluids. Microorganisms in protective clothing materials depend on the following factors:
    1. Physical and chemical properties of fabrics: including thickness, pore size and water repellency
    2. Shape, size and other characteristics of microorganisms: including morphology, motility and adaptation to extreme environments
    3. Carrier characteristics: including surface tension, volume and viscosity
    4. External factors: including physical, chemical and thermal stress
    在医疗环境中发现了多种不同的微生物，包括细菌、病毒和一些真菌。微生物的形状和大小各不相同，这将影响它们穿过织物结构的能力。一般来说，真菌比细菌大，细菌比病毒大。例如，HIV病毒是球形的，直径为100-120纳米。埃博拉病毒是一种单链RNA病毒，呈丝状，平均粒径为80nm，平均粒长为974nm-1086nm。
    A variety of different microorganisms have been found in the medical environment, including bacteria, viruses and some fungi. Microbes vary in shape and size, which affects their ability to penetrate the fabric structure. In general, fungi are bigger than bacteria, and bacteria are bigger than viruses. For example, HIV is spherical, with a diameter of 100-120 nanometers. Ebola virus is a single stranded RNA virus, which is filamentous with an average particle size of 80nm and an average length of 974nm-1086nm.
    微生物通过体液、脱落的皮肤细胞、皮棉、灰尘和呼吸液滴等载体进行运输。在极微量的血液或体液中可携带大量微生物，肉眼可能看不到。例如，0.1微升（?L）液滴中乙型肝炎的感染单位数为10000个，这就是为什么它具有很强的传染性和易转移性。在疾病的急性期，血液中的埃博拉病毒RNA水平也迅速增加。一项研究报告了每0.1微升3.4 x 105个RNA拷贝数的平均峰值滴度（即，比乙型肝炎浓度高34倍）。几项研究也曾报道过，当含有微生物的液体渗透到材料中时，微生物也会随之携带，并且在液体不可见的情况下也可以穿透。因此，标准化的测试方法必须足够准确，以检测微生物的渗透，因为这是唯一的方法来确定微生物是否渗透在衣服的任何部分，包括接缝。
    Microorganisms are transported by carriers such as body fluids, exfoliated skin cells, lint, dust and respiratory droplets. A large number of microorganisms can be carried in very small amount of blood or body fluid, which may not be visible to the naked eye. For example, the number of infected units of hepatitis B in 0.1 μ L (μ L) droplet is 10000, which is why it is highly infectious and easy to transfer. In the acute phase of the disease, the level of Ebola virus RNA in the blood also increases rapidly. One study reported an average peak titer of 3.4 x 105 RNA copies per 0.1 microliter (i.e., 34 times higher than the concentration of hepatitis B). Several studies have also reported that when a liquid containing microorganisms penetrates into a material, microorganisms are carried along and can penetrate when the liquid is not visible. Therefore, a standardized test method must be accurate enough to detect microbial penetration, as this is the only way to determine if the microorganism is penetrating any part of the garment, including seams.