1.1 本规程描述了收集工作活动中产生的非纤维气载金属纳米颗粒的指定设备和程序。 1.2 纳米颗粒呼吸沉积（NRD）取样器设计为遵循基于国际辐射防护委员会（ICRP）模型的纳米颗粒物（NPM）沉积曲线，用于沉积小于300 nm的颗粒（亚微米颗粒的最小沉积），同时去除较大的颗粒 ( 1. ) . 2. 1.3 本规程适用于工作过程中的个人和区域采样以及可能产生金属纳米颗粒的情况（例如，焊接、熔炼、靶场）。 1.4 本规程旨在供在使用职业空气采样设备（如旋风采样器）方面经验丰富的专业人员使用。 1.5 本规程不适用于碳纳米管等纤维纳米颗粒的取样。 1.6 由于适用装置和仪器的不同品牌和型号不同，因此未提供详细的操作说明。用户应遵循特定设备制造商提供的具体说明。本规程不涉及不同装置的比较精度，也不涉及相同品牌和型号的仪器之间的精度。 1.7 本规程包含解释性注释，不属于该方法的强制性要求。 1.8 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.9 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.10 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 暴露于高浓度的雾化细颗粒和超细非纤维金属颗粒中，包括在涉及高能的过程（如焊接或冶炼）中产生的锰（Mn）、铬（Cr）和镍（Ni），可能会对健康产生有害影响。 动物和流行病学研究将焊接和相关工作过程与广泛的不良健康影响相关联，包括上呼吸道影响（鼻炎和喉炎）、肺部影响（肺炎、慢性支气管炎、肺功能下降）、潜在的神经障碍（锰诱发的帕金森病）以及肺癌和尘肺死亡率高。锰与神经系统疾病有关。 5.2 由金属或其氧化物和硫属化合物制成的纳米颗粒已被发现有许多工业用途。纳米金属的示例包括银（Ag）、金（Au）、铁（Fe）、铜（Cu）、镉（Cd）、锌（Zn）、铂（Pt）和铅（Pd）；纳米金属氧化物的示例包括氧化铝（Al 2. O 3. )，氧化镁（MgO），二氧化锆（ZrO 2. )，氧化铈（IV）（CeO 2. )，二氧化钛（TiO 2. )，氧化锌（ZnO），氧化铁（III）（Fe 2. O 3. )，和二氧化锡（SnO）；纳米金属硫化物的示例包括单硫化铜（CuS）、硫化镉（CdS）、硫化锌（ZnS）、硫化银（AgS）、硫化锡（SnS）和许多镍和钴（Co）的硫化物；纳米金属硒化物的示例包括硒化锌（ZnSe）、硒化镉（CdSe）和硒化汞（HgSe）。这些纳米颗粒的制造和使用都会导致颗粒吸入，并产生不良影响。通常发现，与相同成分的较大颗粒相比，有害健康和细胞效应与吸入纳米颗粒之间存在更强的相关性。 5.3 气溶胶采样方法通常规定使用可吸入和相关采样器采集工作场所空气样本。 当与重量分析相结合时，这些暴露评估方法以及呼吸和胸部取样器（ISO 7708）的使用不足以测量纳米颗粒暴露。大颗粒（>1μm）的重量大大超过典型烟雾中的纳米颗粒，因此模糊了通过重量分析过滤器采样检测纳米颗粒的能力。此外，大多数尺寸选择性采样器收集气溶胶部分中可渗透到呼吸道的所有颗粒。受撞击、拦截和扩散（ISO 13138）原则控制的颗粒沉积通常被这些采样器高估。 5.4 除了较大的颗粒外，还需要测量空气中的纳米颗粒浓度。NRD取样器以类似于其在人类呼吸道中典型沉积的方式选择性收集纳米颗粒。 正如ICRP所描述的那样，纳米颗粒的不断运动使其扩散并可能沉积在呼吸道的所有区域，从头部气道到深肺泡区域 ( 2. ) . NRD取样器设计为遵循基于ICRP模型的纳米颗粒物（NPM）沉积曲线，用于沉积小于300 nm的颗粒（亚微米颗粒的最小沉积），同时去除较大的颗粒 ( 1. ) . 尺寸选择性取样器（可呼吸、胸部和可吸入）模拟颗粒渗透，而不是颗粒沉积。许多关于焊接烟尘的研究表明，焊接烟尘颗粒的尺寸分布支撑着气道沉积的最小值，因此大部分烟尘在吸入后不会沉积在气道中 ( 3- 7. ) . 然而，使用NRD取样器从沉积估算角度接近暴露评估 ( 8. ) 并为测量纳米颗粒暴露对工人（如焊工）造成的实际危害提供了一个更相关的生理程序。这一知识对毒理学研究的发展至关重要，毒理学研究旨在发现含金属纳米颗粒的沉积与不良健康影响之间的联系。 5.5 焊接烟雾主要由偶发纳米颗粒（纳米级任何外部尺寸的颗粒）控制，但也包括飞溅产生的较大颗粒。目前的动物和流行病学研究调查了接触焊接烟尘的情况，但没有区分纳米粒子和较大颗粒。研究发现，与较大颗粒相比，焊接烟尘纳米颗粒在细胞水平上诱导更多毒性作用，并产生更多活性氧（ROS）活性。 5.6 最初设计了一种NRD取样器，使用尼龙滤网作为收集纳米颗粒的扩散阶段 ( 1. ) ，包括焊接烟尘 ( 8. , 9 ) ，尽管当时注意到本实施例的实验室试验还不包括团聚颗粒，例如表征焊接烟尘的颗粒。后来发现，随着凝聚纳米颗粒的样品收集进展到更高的负载量，另一种收集机制，即拦截，发挥了重要作用。研究发现，聚集颗粒用尼龙筛网的性能受累积纳米颗粒分数负载大于1 mg的影响。性能变化伴随着滤网压降增加至14.3 kPa（57 in.水） ( 5. ) ，这将导致许多采样泵出现故障。在美国政府卫生学家会议（ACGIH）上，阈值（TLV） 5. 对于5 mg/m的焊接烟尘 3. ，2.5升/分钟的一小时样品将收集0.75毫克。由于焊接烟尘的纳米粒子部分通常不到空气中总质量的一半 ( 3. ) 在现场研究中，尼龙滤网可以有效地对焊接烟尘进行1小时或更少的采样 ( 9 ) . 5.7 一种新的扩散阶段基材，聚氨酯泡沫，具有更类似于人体气道的特性（例如，参考 ( 10 ) )并且可能更适合在更高负载情况下收集凝聚材料 ( 11 ) . 此外，聚氨酯泡沫不含二氧化钛，因此该取样器可用于评估纳米二氧化钛。 5.8 当采样直径高达100 nm的球形纳米颗粒时，使用聚氨酯泡沫的取样器可以很好地模拟ICRP沉积曲线。随着尺寸和形状因子的增加，泡沫中收集的团聚颗粒开始显示出与简单曲线的显著偏差 ( 11 ) . 在Ref的图3中 ( 11 ) ，根据气溶胶的动态形状因子调整粒子通过泡沫的曲线建模行为，并显示采样器采集在较大粒径下继续匹配修改后的曲线。由于泡沫已被证明是较大颗粒尺寸下肺部沉积的有用替代物，因此可以假设调整后的泡沫模型也将模拟肺部纳米颗粒团聚体的行为。在人肺中观察到团聚二氧化硅颗粒中更大的团聚体沉积增强- 演员阵容 ( 12 ) 证明可能需要调整此尺寸范围内团聚体的ICRP曲线。然而，在未来的研究确定对人体气道中凝聚颗粒的ICRP沉积曲线进行更精确的调整之前，泡沫收集与人体气道沉积的关系仍然是一个假设。 5.9 实验需要通过NRD采样器准确测量流速，其中将采样设备和过滤材料与其捕获的气溶胶的粒度分布进行比较。空气流速影响采样器捕捉特定空气动力学尺寸颗粒的效率。此外，通过采样器的空气流速可能会影响捕集在过滤器上并沉积在采样器收集基板和壁上的气溶胶颗粒的分布。 为了从大量捕获的颗粒中确定气溶胶浓度，有必要准确设置和测量流速。 注2: 请参阅指南 E1370 为制定适当的暴露评估和测量策略提供指导。

1.1 This practice describes specified apparatus and procedures for collection of non-fibrous airborne metal nanoparticles generated during work activities. 1.2 Nanoparticle respiratory deposition (NRD) samplers are designed to follow a nanoparticulate matter (NPM) deposition curve based on the International Commission on Radiological Protection (ICRP) model for deposition of particles smaller than 300 nm (the minimum deposition for submicrometre particles) while removing the larger particles ( 1 ) . 2 1.3 This practice is applicable to personal and area sampling during work processes and situations where metal nanoparticles may be generated (for example, welding, smelting, shooting ranges). 1.4 This practice is intended for use by professionals experienced in the use of devices for occupational air sampling (such as cyclone samplers). 1.5 This practice is not applicable to the sampling of fibrous nanoparticles such as carbon nanotubes. 1.6 Detailed operating instructions are not provided owing to differences among various makes and models of suitable devices and instruments. The user is expected to follow specific instructions provided by the manufacturers of particular items of equipment. This practice does not address comparative accuracy of different devices nor the precision between instruments of the same make and model. 1.7 This practice contains notes that are explanatory and are not part of the mandatory requirements of the method. 1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Exposures to high concentrations of aerosolized fine and ultrafine non-fibrous metal particles, including manganese (Mn), chromium (Cr), and nickel (Ni) generated during processes that involve high energy such as welding or smelting, may elicit deleterious health effects. Animal and epidemiological studies have associated welding and related work processes with a wide range of adverse health effects, including upper respiratory effects (rhinitis and laryngitis), pulmonary effects (pneumonitis, chronic bronchitis, decreased pulmonary function), potential neurological disorders (manganese-induced Parkinsonism), and high lung cancer and pneumoconiosis death rates. Manganese has been associated with neurological diseases. 5.2 Nanoparticles produced from metals, or their oxides and chalcogenides, have found many industrial uses. Examples of nanometals include silver (Ag), gold (Au), iron (Fe), copper (Cu), cadmium (Cd), zinc (Zn), platinum (Pt), and lead (Pd); examples of nanometal oxides include aluminium oxide (Al 2 O 3 ), magnesium oxide (MgO), zirconium dioxide (ZrO 2 ), cerium(IV) oxide (CeO 2 ), titanium dioxide (TiO 2 ), zinc oxide (ZnO), iron(III) oxide (Fe 2 O 3 ), and tin(II) oxide (SnO); examples of nanometal sulfides include copper monosulfide (CuS), cadmium sulfide (CdS), zinc sulfide (ZnS), silver sulfide (AgS), tin sulfide (SnS), and many sulfides of Ni and cobalt (Co); examples of nanometal selenides include zinc selenide (ZnSe), cadmium selenide (CdSe), and mercury selenide (HgSe). Both the manufacture and use of these nanoparticles can result in particle inhalation, and consequent ill-effects. A stronger association has often been found between adverse health and cellular effects and inhalation of nanoparticles compared to larger particles of the same composition. 5.3 Aerosol sampling methods generally specify the collection of workplace air samples using inhalable and related samplers. These exposure assessment methods, as well as the use of respirable and thoracic samplers (ISO 7708), are inadequate for measurements of nanoparticle exposure when paired with gravimetric analysis. Large particles (>1 μm) weigh substantially more than nanoparticles typical of fumes and, consequently, obscure the ability to detect nanoparticles through gravimetric filter sampling. Additionally, most size-selective samplers collect all particles in the fraction of aerosol that can penetrate into the respiratory tract. Particle deposition, which is governed by the principles of impaction, interception, and diffusion (ISO 13138), is typically overestimated by these samplers. 5.4 There is a need to measure nanoparticle airborne concentrations apart from larger particles. An NRD sampler selectively collects nanoparticles in a manner similar to their typical deposition in the human respiratory tract. The constant motion of nanoparticles causes them to diffuse and potentially deposit in all regions of the respiratory tract, from the head airways to the deep alveolar region, as described by the ICRP ( 2 ) . NRD samplers are designed to follow a nanoparticulate matter (NPM) deposition curve based on the ICRP model for deposition of particles smaller than 300 nm (the minimum in deposition for submicrometre particles) while removing the larger particles ( 1 ) . Size-selective samplers (respirable, thoracic, and inhalable) mimic particle penetration rather than particle deposition. Many studies of welding fume have noted that size distribution of welding fume particles brackets the airways deposition minimum so that a substantial proportion of the fume is not deposited in the airways following inhalation ( 3- 7 ) . The use of an NRD sampler, however, approaches exposure assessment from a deposition estimation perspective ( 8 ) and provides a more relevant and physiological procedure for measuring actual hazards to workers (such as welders) posed by nanoparticle exposure. This knowledge is critical to the development of toxicological studies aimed at finding links between deposition of metal-containing nanoparticles and adverse health effects. 5.5 Welding fumes are dominated by incidental nanoparticles (particles with any external dimension in the nanoscale), but also include larger particles generated by splatter. Current animal and epidemiological studies investigate exposure to welding fumes without differentiating between nanoparticles and larger particles. Welding fume nanoparticles have been found to induce more toxic effects at the cellular level and to generate more reactive oxygen species (ROS) activity when compared to larger particles. 5.6 An NRD sampler was initially designed with nylon screens as the diffusion stage for the collection of nanoparticles ( 1 ) , including welding fume ( 8 , 9 ) , although it was noted at the time that laboratory tests of this embodiment had not also included agglomerated particles, such as those which characterize welding fume. An additional collection mechanism, interception, was later found to play an important role as the sample collection of agglomerated nanoparticles progressed to higher loadings. Performance of the nylon screens for agglomerated particles was found to be affected by accumulated nanoparticle fraction loadings greater than 1 mg. The change in performance was accompanied by an increase in pressure drop across the screens to 14.3 kPa (57 in. of water) ( 5 ) , which would cause many sampling pumps to fault. At the American Conference of Governmental Hygienists (ACGIH) Threshold Limit Value (TLV) 5 for welding fume of 5 mg/m 3 , a one-hour sample at 2.5 L/min will collect 0.75 mg. Since the nanoparticle fraction of welding fume is typically less than half the total mass in air ( 3 ) , the nylon screens are effective in sampling welding fume for one-hour or less as was borne out in field studies ( 9 ) . 5.7 A new diffusion stage substrate, polyurethane foam, has characteristics more closely resembling human airways (example, Ref ( 10 ) ) and may be preferable for collecting agglomerated materials in higher loading scenarios ( 11 ) . In addition, polyurethane foam does not contain titanium dioxide allowing this sampler to be used to assess nanoparticle titanium dioxide. 5.8 The sampler with polyurethane foam has been shown to mimic the ICRP deposition curve closely when sampling spherical nanoparticles up to 100 nm diameter. Agglomerated particles collected in foam begin to show significant deviations from the simple curve as their size and shape factor increase ( 11 ) . In Figure 3 of Ref ( 11 ) , the curve modeling behavior of particles through foam is adjusted according to the dynamic shape factor of the aerosol and the sampler collection is shown to continue to match the modified curve at larger particle sizes. Since foam has proven to be a useful surrogate for lung deposition at larger particle sizes, it can be hypothesized that the adjusted foam model also will mimic the behavior of nanoparticle agglomerates in the lung. Enhanced deposition of larger agglomerates has been observed for agglomerated silica particles in human lung-casts ( 12 ) demonstrating that it may be necessary for an adjustment to the ICRP curve for agglomerates in this size range. However, until future research has identified a more precise adjustment to the ICRP deposition curve for agglomerated particles in the human airways the relationship of foam collection to human airways deposition remains a hypothesis. 5.9 An accurate measurement of flow rate through an NRD sampler is required for experiments where sampling devices and filter materials are to be compared as to the size distribution aerosol they capture. Air flow rate affects the efficiency with which a sampler will capture a particular aerodynamic size of particles. Furthermore, air flow rate through a sampler may affect the distribution of aerosol particles captured on the filters and deposited on the sampler collection substrates and walls. To determine aerosol concentration from a mass of captured particles it is necessary to set and measure flow rates accurately. Note 2: Refer to Guide E1370 for guidance on the development of appropriate exposure assessment and measurement strategies.