BASIC PRINCIPLES IN OCCUPATIONAL HYGIENE Day 2 2
BASIC PRINCIPLES IN OCCUPATIONAL HYGIENE 职业卫生基本原则 Day 2 第 2天
Physical States 物理状态 • • • Vapour - the gaseous state of a substance which is liquid at 25°C and 760 mm Hg (STP). 水蒸汽——在 25℃和760毫米汞柱(STP)条件下为液体形式的物质的气态。 Mist - liquid particles, large size generally produced by bubbling, splashing or boiling of a liquid. 雾——液体颗粒,尺寸较大,由液体起泡、飞溅或煮沸形成。 Fume - Solid particles produced by condensation from a liquid or a reaction between two gases. The particle size of a fume <1 micron (µm) diameter anything larger is considered a dust particle. 悬浮粒——液体冷凝或气体反应所产生的固体颗粒。直径小于1微米(μm)的粒子均为尘埃粒子。 Dust - particles of solid material in the broad size range of 1 micron to 1 millimetre diameter. Anything of a larger particle size is considered to be grit and will be too heavy to remain airborne. 灰尘——固体材料颗粒,直径大小在 1微米至 1毫米之间。超出此方位的颗粒则为砂砾,因其重 量过大,故无法漂浮在空气中。 Aerosol - general term for the dispersions of solid or liquid particles of microscopic size in a gaseous medium e. g. fog, smoke etc. although commonly used to term fine liquid spray (e. g. ‘aerosol can’). 浮质——在气态介质(例如雾等)中微观尺寸的固体或液体颗粒分散质总称,虽然常指细密液 体喷雾(如气雾罐)。 Fibre – Solid particulate which are long and thin i. e. have a high aspect ratio of length to breadth. 纤维——薄长的固体颗粒物,纵横比高。
Sampling Techniques 取样技术 • • • Appropriate for the purpose of the measurement. 适于测量。 ‘Monitoring’ or ‘Sampling’ - the use of valid and suitable techniques to derive a quantitative estimate of the Personal Exposure. “监控”或“取样”——使用适当有效的技术,对单次接触进行定量预估。 Only validated monitoring methods should be used. 仅使用有效的监测方法。 – HSE, NIOSH or Other National Standards – HSE、NIOSH或其它的国家标准 – May be legislation/country specific – • • 可以具有立法/国家特色的 Personal Exposures. 单次接触 Static Sampling. 静态取样
Short Term Sampling 短期取样 浓 度 时间
Long Term Sampling 长期取样 浓 度 时间
Continuous Monitoring 连续监测 浓 度 时间
Bulk Sampling 大量取样 • Taken and analysed for identification purposes. • 取样,进行内容物确认分析 • Not possible to relate the results to the airborne concentrations. • 不可能确定结果与空气中浓度之间的关系 • Can be use to show spread of contamination. • 可用于显示污染的扩散。
Sampling for Particulates 微粒取样
Particle size 粒度 • Total inhalable dust is the fraction of airborne material which enters the nose and mouth during breathing and is therefore liable to deposition anywhere in the respiratory tract. The particle sizes of total inhalable dust are up to 100 microns. • 可吸入总粉尘是气载物质的一部分,在呼吸过程中进入口鼻,容易 在呼吸道中沉淀。可吸入总粉尘的颗粒大小最大 100微米。 • Respirable dust is that fraction that penetrates to the deep lung where gas exchange takes place. The particle sizes of respirable dust are up to 10 microns. • 可吸入粉尘是进入气体交换的肺部深处的物质中的一部分。可吸入 粉尘的颗粒大小最大 10微米。
Elements of a Sampling System 取样系统的要素 Sampling train 取样组合 • Pump • 泵 • Filter 取样器 直径30毫米的 呼吸区 • 过滤器 • Sampling Head / Size Separator. • 取样头 /粒度分离器 泵 Source: SKC 资料来源:SKC
Sampling Head / Size Seperator 取样头 /粒度分离器 IOM Head Total Inhalable Dust Cyclone Respirable Dust IOM 取样头 适用于可吸入总粉尘 气旋式取样头 适用于可吸入粉尘 Source: SKC 资料来源:SKC
Samples Collected for Welding Fume 焊接烟尘取样样本 Source: Adrian Hirst 资料来源: Adrian Hirst
Calculation of Exposure 接触限值计算 Concentration (mg/m 3) 浓度 (mg/m 3) = = Weight gain (mg). Flow rate (litre/min) x Time (min) 颗粒重量 (mg). 流速 (litre/min) x 时间 (min) OR 或 = 浓度 (mg/m 3) = Weight gain (mg) Flow rate (litre/min) x Time (min) x 1000 颗粒重量 (mg). 流速 (litre/min) x 时间 (min) x 1000
Weight (mass) Gain 颗粒重量(质量) Source: Wikimedia Commons 资料来源: 维基资料共享
Flow rate 流速 Source: Adrian Hirst 资料来源:Adrian Hirst
Flow rate 流速 Source: Adrian Hirst 资料来源:Adrian Hirst
Calculation of Exposure 接触限值计算 Concentration (mg/m 3) 浓度 (mg/m 3) = = Weight gain (mg). Flow rate (litre/min) x Time (min) x 1000 颗粒重量 (mg). 流速 (litre/min) x 时间 (min) x 1000
Calculation of Personal Exposure 单次接触限值的计算 Time of sample: 09: 12 to 15: 45 取样时间: 09: 12到 15: 45 Flow Rate of Pump = 2. 0 litres per minute 泵的流速为每分钟 2. 0升 Weight of Filter before exposure: 25. 82 mg 接触前过滤的重量: 25. 82毫克 Weight of Filter after exposure: 27. 21 mg 接触后过滤的重量: 27. 21毫克 What is the Personal Exposure? 什么是单次接触限值?
Calculation of Personal Exposure 单次接触限值的计算 Time of sample: 09: 12 to 15: 45 = 5 hours and 33 minutes = 333 mins 取样时间: 09: 12至 15: 45 = 5小时 33分钟= 333分钟 Sample Volume = Flow Rate of Pump x Time 样本体积=泵的流速x时间 Sample Volume = 2. 0 lpm x 333 mins 样本体积=2. 0 lpm x 333 mins Sample Volume = 666 litres 样本体积=666 litres Sample Volume = 0. 666 m 3 样本体积=0. 666 m 3 Mass of material on filter = 27. 21 – 25. 82 mg 过滤器上的材料重量= 27. 21 - 25. 82毫克 Mass of material on filter = 1. 39 mg 过滤器上的材料重量= 1. 39毫克 Personal Exposure = 1. 39 mg / 0. 666 m 3 单次接触限值= 1. 39 mg / 0. 666 m 3 Personal Exposure = 2. 09 mg/m 3 单次接触限值=2. 09 mg/m 3
Sampling for Gases and Vapours 气体和蒸气的取样 • • Active Sampling - i. e. by means of a mechanic/sampling pump method. 主动取样——通过机械/取样泵方法 – Sorbent Tubes –吸附管 • • Passive Sampling 被动取样
Sorbent Tubes 吸附管 Source: Adrian Hirst 资料来源: Adrian Hirst
Equipment used for Taking Grab Sample 瞬时取样用设备 Indicator Tubes指示管 Source: Drager 资料来源:Drager
Equipment used for Taking Grab Sample 瞬时取样用设备 Sample Bags 取样袋 Source: SKC 来源:SKC
Equipment used for Taking Grab Sample 瞬时取样用设备 Equipment Type 设备 类型 Detector Tubes检测管 Mode of Operation Advantages Disadvantages 操作模式 优点 缺点 Chemical reaction produces colour change 化学反应导致 Instant result, easy to use Not very accurate, often tubes are non-specific 颜色变化 Gas sampling bags, syringes and containers 气体取样袋、注射器和容器 Paper tapes/ impregnated filters 试纸/浸入式滤纸 Electrochemical Detectors 电化学检测器 Gold Film Mercury Vapour Analyser 金膜汞分析仪 Pumps used to fill a bag or container to be sent for analysis 结果立即可见,使用方便 Simple, light, cheap 精度低、仅适用于常规管道 No concentration effect, losses can occur. Not instant. 泵将气体充入取样袋或取样 器中,随后进行分析 简单、重量轻、价格便宜 无集聚效果,可能出现损耗, 不能即时显示。 Air drawn through paper impregnated with chemical reagents producing a colour change Direct reading, can be used for other sampling techniques Stain can fade. Personal samplers bulky. Non-specific 直接读取,也适用其它取样 技术 染色位置会褪色、个人取样 器,笨重,无专业性。 Direct reading, simple, lightweight. Also used for other sampling techniques Expensive, calibration required, non-specific 将试纸浸入化学试剂,出现 颜色变化,以此来吸入空气 Substance interacts with electrochemical detector cell 用电化学检测器检测物质 Mercury vapour increases resistance of gold film sensor 汞蒸气会增加金膜传感器的 电阻 直接读取、简单、轻便。也 适用其它取样技术。 Simple, lightweight specific 简单,重量轻、专业 价格昂贵,需要校准,无专 业性。 Expensive, requires regular cleaning and calibration 价格昂贵,需要定期清洗和 校准
Equipment used for taking short and long term Samples 短期和长期取样用设备 Source: 3 M 资料来源: 3 M Source: SKC 资料来源:SKC
Equipment used for taking short and long term Samples 短期和长期取样用设备 Equipment Type设备类型 Mode of Operation 操作模式 Advantages 优点 Disadvantages 缺点 Pumped samplers with solid sorbent traps e. g. charcoal or tenax 泵送取样器,配置有固 体吸附剂陷阱,例如木 炭或苯基对苯醚 Air is drawn through a tube on which the substances of interest are collected 空气通过物质采集管道 吸入 Accurate, reliable, used in many official methods 精度高、可靠性高,被 许多正式方法采用 Needs complex analysis systems, result not instant. 需要复杂的分析系统, 结果不能即时产生。 Diffusive Samplers 扩散式取样器 Contaminant diffuses through a membrane onto a sorbent bed of filter material. 污染物通过过滤材料吸 附剂床上的膜出现扩散 Small, robust, cheap, acceptable to operators 体积小,功能强大,价 格便宜,受操作人员喜 爱 May require validation in field conditions. Needs complex analysis systems. Result not instant. 需要现场通风,需要复 杂的分析系统,结果不 能即时产生。 Bubblers/ Impingers 气泡型/冲击式取样器 Air is bubbled through a solvent or reactive solution 空气通过溶剂或反应溶 液形成气泡 Solution obtained can be analysed directly. 获取溶液时可直接进行 分析。 Wearer carries a glass vial. Devices bulky, losses can occur 携带者还需要携带玻璃 小瓶,设备笨重,会有 损耗。
Equipment used for continuous Sampling 连续取样用设备 Mini RAE 3000 Portable PID 迷你RAE 3000便携式PID SKC Real Time Dust Monitor SKC实时粉尘监测仪
Equipment used for continuous Sampling 连续取样用设备 Equipment Type设备类型 Mode of Operation 操作模式 Advantages 优点 Disadvantages 缺点 Flame Ionisation e. g. organic vapour analyser (OVA) or total vapour analyser (TVA) 火焰电离检测器,例如 有机蒸汽检测仪(OVA) 或总蒸汽检测仪 Combustion of organics in an air / hydrogen flame produces ions – sensed by electrodes and converted into a voltage signal 有机物在 空气/氢火焰中燃烧,产 生离子——电极感应离 子,转换成电压信号 Portable Usually intrinsically Safe 便携式,通常是本质安 全型 Limited on range and specificity of contaminants 可检测的污染物范围和 特征有限 Infrared e. g. Miran Analyser 红外线,例如米朗分析 仪 Absorption of IR radiation used to measure the concentration of substance 吸收红外线, 用于测量物质浓度 Semi-portable, Limited in the compounds it can detect 半移动式,可检 测组成专业 Bulky, non-intrinsically safe 笨重,非本质安全型 Ultraviolet 紫外线 Absorbance of ultraviolet 吸收紫外线 Portable 便携式 Interferences, calibration, not intrinsically safe 有干扰,需校准,非本 质安全型
Fixed Position Sampling 固定位置取样 • • Normally personal samples taken. 通常情况下,需要个人进行取样。 Fixed Position Samples useful to 固定位置样本好处: – Provide information about contamination from fixed sources – 提供有关固定源的污染物信息 – Assess effectiveness of control measures e. g. local exhaust ventilation. – 评估控制措施的有效性,例如局部排风。 • • Care has to be exercised in interpreting the results. 说明结果时应小心谨慎。 Fixed position samples cannot be used to establish personal exposures or be compared to hygiene standards. 固定位置样本不能用于确定单次接触限值,不能与卫生标准相比。
Sampling Methods 取样方法 • Validated methods of sampling and analysis should be used e. g. HSE, NIOSH • 应使用通过验证的取样和分析方法,如HSE、NIOSH • National Standards may specify particular methods. • 国家标准可能会指定相关方法。
Sampling Strategies 取样策略 Most sampling done to assess personal exposure, but also done to: 取样主要用于评估单次接触限值,但也可以用于 – – – Identification of airborne contaminants 识别气载污染物 Identify leaks and spillages 确定是否有泄露和溢漏 Assessment of the Effectiveness of Control Measures 对控制措施的有效性进行评估 Strategy employed needs to be varied depending upon the aims of the survey. 根据勘测目的采用取样策略。
Sampling Records 取样记录 • Full details of the sampling performed should be recorded and retained. • 应记录和保持详细的取样信息。 – When the monitoring was done – 何时进行监测? – Who and where was monitored – 何人和何地进行监测? – Details of the equipment used – 使用设备详情 – The operations in progress at the time of the survey – 勘测时的操作 • In most countries records of monitoring should be available to employees or their representatives. • 在大多数国家,规定应向员 或其代表提供监测记录。
Sample Handling 样本处理 • Inappropriate handling and transport of sampled materials may give rise to losses or contamination. • 样本运输和处理不当可能会导致损耗或污染。 – The type of container used – 使用容器的类型 – Temperature – 温度 – Sunlight – 阳光 – Time before analysis – 分析前的时间 – Contamination. – 污染 • Advice can usually be obtained from the laboratory undertaking the analysis. • 实施分析的实验室通常会提供建议。
Collected Sample for Analysis 采集样本,实施分析
Methods of Analysis 分析方法 There are numerous analytical techniques available for the analysis of airborne contaminants. 目前有多种可以对气载污染物进行分析的方法。 – Organic Vapours - gas chromatograph (GC) complete with a flame ionisation detection (FID). – 有机蒸汽——气相色谱仪(GC),和火焰离子化检测器(FID)。 – Inorganic Gases - GC/thermal conductivity methods, photometric and microcoulometry, chemiluminescence. – 无机气体——气相色谱/导热系数方法、光度计和微库仑分析法、化学发光法。 – Organic Particulate Matter - high pressure liquid chromatography (HPLC), infra-red (IR) or ultraviolet (UV) spectrometery. – 有机颗粒物——高压液相色谱(HPLC)、红外(IR)或紫外(UV)光谱分析。 – Metals and their Compounds – ICP, Atomic Absorption (AA). – 金属及其化合物——ICP,原子吸收(AA)。 – Mineral Dusts – Microscopy, gravimetery, x-ray diffraction. – 矿物粉尘——显微镜、比重计、射线衍射。 Calibration and Quality Control 校准和质量控制 – Schemes - WASP or RICE (both UK) or PAT (US). – 标准—— WASP 或RICE(英国)或PAT(美国)。 – Accreditation - UKAS (UK) or NATA (Australia). – 认证—— UKAS(英国)或NATA(澳大利亚)。
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