用扩散法被动式个体采样器同时测定空气中二氧化硫和二氧化氮

本文介绍了用被动式个体采样器同时测定空气中ＳＯ２和ＮＯ２的方法,吸收层用三乙醇胺（２０％）＋碳酸钠（５％）溶液浸渍的滤纸,采样后分成两等分,分别测定ＳＯ２和ＮＯ２浓度。与有动力的溶液吸收管现场对比验证,表明两者结果是一致的。在外环境监测时,为了克服风速的影响,可将被动式个体采样器放在ＴＳＰ流量采样器的帽形采样头中,这样可同时测定环境空气中ＴＳＰ、ＳＯ２和ＮＯ２。     

被动式个体采样器在环境监测中的应用

被动式个体采样器在环境监测中的应用刘雪锦，史黎薇（山东省环境卫生监测站２５００１４）（中国预防医学科学院环境卫生监测所１０００２１）被动式个体采样器是利用气体分子扩散或渗透原理采集空气中气态污染物，然后测定其浓度的一种监测仪器。特点是采评体积小，不用...     

浅析被动采样器监测环境空气质量数据的可比性

对被动采样器与空气自动站监测环境空气质量进行了全年的对比实验,并对大量的监测数据进行了规范的处理分析。结果表明,被动采样器在环境条件持续稳定满足采样条件时,被动采样器与自动站监测结果无显著性差异;在环境条件不能持续稳定满足采样条件时,二者监测结果有显著性差异,但仍有较大的相关性。     

北欧地区大气无动力监测技术在亚热带高原的应用研究

无动力监测技术是一种成本低、效益高、灵敏而准确的空气气态污染物平均浓度监测采样方法,其连续时间覆盖可从几个小时到一个月.以月为采样周期时检测范围SO2为0.1～200μg/m3,NO2为0.1～400μg/m3,高灵敏度的检测下限可以满足低浓度背景区域内空气气态污染物的检出.其主要优点是采样器体积小、重量轻、无噪音、可重复利用、不用电、不需要技术人员、费用极低.采样器能在采样前后的常温条件下稳定几个月,因此能用于边远地区的环境监测.在检查模型计算和验证研究、健康影响评估、交通规划和绘制不同空气污染物在城市区域的高空间分辨率浓度分布图时,无动力采样器是最有价值的污染物高空间分辨率测定方法.文章所报道的是无动力采样技术的实际运用研究,是中瑞国际合作某项目的一部分,由瑞典环境科学研究院(IVL)与云南省环境监测中心站(YEMCS)共同完成.     

利用Triolein半渗透膜采样技术测定洋河水中的优先污染物

应用Ｔｒｉｏｌｅｉｎ半渗透膜采样器采集了河北洋河宣化至官厅水库河段水样,根据测定采样器中多氯联苯污染物（ＰＣＢｓ）及其它优先污染物浓度,可以估算这些污染物在河段水体中的平均浓度。将结果与同时同地采集的水样,经萃取浓缩后分析得到的结果比较,发现对于不同类型污染物,二者符合程度不同。本研究证明半渗透膜被动采样技术可用于水中多氯联苯等难降解污染物的定量监测,有可能在我国的优先污染物监测工作中发挥作用     

环境空气连续采样系统的改进

目前 ,很多环境监测站已采用 2 4ｈ连续采样监测代替了过去的季五日采样法。连续采样监测系统由空气自动连续采样器、总悬浮颗粒物 (ＴＳＰ)采样器和辅助风机 (主要是采样管道引风机和采样亭排气扇 )组成。空气连续采样器设有时控系统 ,可以根据要求随时启停 ,ＴＳＰ采样器无隔日采样控制系统 ,辅助风机则经常出现仪器停止采样后继续运转的情况。对此 ,今利用空气连续采样器的时控系统 ,增加一个ＣＪ1 0 - 5型交流接触器 ,实现了对采样系统所有设备的控制 ,使之都能按要求启停 ,从而节约了用电量 ,减少了风机的不必要运转。现采用的是ＨＢ -…     

限流孔烟气采样器的研制及应用

介绍了限流孔烟气采样器的设计原理、主要技术指标、设计指标说明及采样器主要性能。通过测定ＳＯ２标准气体和比对试验，表明限流孔烟气采样器控制流量稳定，计量采气体积准确，应用结果满意。     

废水COD_(Cr)排污总量控制监测

为实现我国对ＣＯＤＣｒ排污总量控制,提出了ＣＯＤＣｒ现场监测的实施方法及总量监测方法。各排污单位必须配备污水流量计、自动采样器或ＣＯＤＣｒ在线连续自动监测仪等,对污水中ＣＯＤＣｒ的排放总量实施监测。同时着重介绍了ＣＯＤＣｒ在线连续自动监测仪。     

大水量采样器,采样技术在环境监测中的应用

在环境监测工作中,采样是重要步骤,一些先进国家的环境保护机构对发展水中痕量污染物的富集采样技术极为重视,自动采样器(装置)得到广泛应用.美国国家环保局(EPA)下属的辛辛那提环境监测与支持实验室编著的《水与废水采样及样品保存手册》一书,专门介绍了一些自动采样器,认为自动采样器的使用为进行环境污染监测和筛选环境水样中的优先监测物和致突变物质,提供了方便,使过去因工作量大而无法广泛开展的工作成为可能.采样器以及采样技术的发展水平反映了一个国家环境监测水平.     

徐州市区空气中有机污染现状与变化规律

通过建立和完善空气中有机污染物的分析方法,对徐州市区空气中的有机污染物开展了全面详细的探查,弄清了市区空气中有机污染物的污染现状及时空变化规律,填补了徐州市空气监测数据中的有机污染物的空白,为开展空气有机污染物的调查和监测奠定了一定的基础。     

A two-stage cyclone using microcentrifuge tubes for personal bioaerosol sampling

Personal aerosol samplers are widely used to monitor human exposure to airborne materials. For bioaerosols, interest is growing in analyzing samples using molecular and immunological techniques. This paper presents a personal sampler that uses a two-stage cyclone to collect bioaerosols into disposable 1.5 ml Eppendorf-type microcentrifuge tubes. Samples can be processed in the tubes for polymerase chain reaction (PCR) or immunoassays, and the use of multiple stages fractionates aerosol particles by aerodynamic diameter. The sampler was tested using fluorescent microspheres and aerosolized fungal spores. The sampler had first and second stage cut-off diameters of 2.6 microm and 1.6 microm at 2 l min(-1)(geometric standard deviation, GSD = 1.45 and 1.75), and 1.8 microm and 1 microm at 3.5 l min(-1)(GSD = 1.42 and 1.55). The sampler aspiration efficiency was >or=98% at both flow rates for particles with aerodynamic diameters of 3.1 microm or less. For 6.2 microm particles, the aspiration efficiency was 89% at 2 l min(-1) and 96% at 3.5 l min(-1). At 3.5 l min(-1), the sampler collected 92% of aerosolized Aspergillus versicolor and Penicillium chrysogenum spores inside the two microcentrifuge tubes, with less than 0.4% of the spores collecting on the back-up filter. The design and techniques given here are suitable for personal bioaerosol sampling, and could also be adapted to design larger aerosol samplers for longer-term atmospheric and indoor air quality sampling.     

挥发性有机物污染土壤样品采样方法比较

以苯系物污染土壤样品的采集为例,比较了4种不同采样方法导致样品检测结果的差异。其中,方法 1将样品装填至广口瓶内并压实密封,方法2采用非扰动采样器采集10 g样品后转移至加有10 mL甲醇保护剂的Vial瓶中密封,方法 3用非扰动采样器采集10 g样品后直接将其密封于采样器内,方法 4用Encore采样器采样后将其密封于采样器内。结果表明,方法 2采集样品的检出率最高,其余3种方法的差异不明显,方法 2采集样品的检出结果 71%以上都大于其余3种方法。而且,对于挥发性较强的苯与甲苯,以方法 2采集的样品91%以上都大于其余3种方法,最大及平均检出浓度高出2~3个数量级。5种不同土质样品检测结果表明,对于有机质含量较低的细砂,方法2的最高及平均检出浓度均高于其余3种方法 1~3个数量级,差异随土壤有机质含量的升高而降低。可见,对于苯系物及挥发性强于苯系物的其他挥发性有机物污染土壤样品的采集,方法 2效果最优,可指定为VOCs污染场地土壤样品的采样方法。     

Validation of a diffusive sampler for NO2

A diffusive sampler for NO2, Willems badge, was validated in laboratory experiments and field tests. The collecting reagent for NO2 in the sampler is triethanolamine, and the analysis is based on a modified colorimetric method, the Saltzman method. The analysis was performed by a flow injection analysis (FIA) technique. The sampling rate for the sampler was determined to be 40.0 ml min-1. There was no effect of NO2 concentration or relative humidity on sampling rate, and the influence of sampling time was found to be small. The detection limit was 4 micrograms m-3 for a 24 h sample. The capacity is high enough to allow sampling of 150 micrograms m-3 for 7 days, which is twice the recommended Swedish short-term (24 h) guideline value as a 98-percentile over 6 months. In field tests, the sampler performed well, even at wind speeds higher than 2 m s-1, and at low temperatures. The overall uncertainty of the method was 24%. The sensitivity and capacity of the method also make it suitable for personal sampling for 2-8 h in working environments.     

Intercomparison of five PM10 monitoring devices and the implications for exposure measurement in epidemiological research

Five different instruments for the determination of the mass concentration of PM10 in air were compared side-by-side for up to 33 days in an undisturbed indoor environment: a tripod mounted BGI Inc. PQ100 gravimetric sampler with a US EPA certified Graseby Andersen PM10 inlet; an Airmetrics Minivol static gravimetric sampler; a Casella cyclone gravimetric personal sampler; an Institute of Occupational Medicine gravimetric PM10 personal sampler; and two TSI Inc. Dustrak real-time optical scattering personal samplers. For 24 h sampling of ambient PM10 concentrations around 10 microg m(-3), the estimated measurement uncertainty for the two gravimetric personal samplers was larger (approximately +/- 20%) compared with estimated measurement uncertainty for the PQ100/Graseby Andersen sampler (< +/- 5%). Measurement uncertainty for the Dustraks was lower (approximately +/- 15% on average) but calibration of the optical response against a reference PM10 method is essential since the Dustraks systematically over-read PM10 determined gravimetrically by a factor approximately 2.2. However, once calibrated, the Dustrak devices demonstrated excellent functionality in terms of ease of portability and real-time data acquisition. Estimated measurement uncertainty for PM10 concentrations determined with the Minivol were +/- 5%. The Minivol data correlated well with PQ100/Graseby Andersen data (r= 0.97, n = 18) but were, on average, 23% greater. The reason for the systematic discrepancy could not be traced. Intercomparison experiments such as these are essential for assessing measurement error and revealing systematic bias. Application of two Dustraks demonstrated the spatial and temporal variability of exposure to PM10 in different walking and transport microenvironments in the city of Edinburgh, UK. For example, very large exposures to PM10 were identified for the lower deck of a double-decker tour bus compared with the open upper deck of the same vehicle. The variability observed emphasises the need to determine truly personal exposure profiles of PM10 for quantifying exposure response relationships for epidemiological studies.     

New experimental methods for the development and evaluation of aerosol samplers

An understanding of the scaling laws governing aerosol sampler performance leads to new options for testing aerosol samplers at small scale in a small laboratory wind tunnel. Two methods are described in this paper. The first involves an extension of what is referred to as the "conventional" approach, in which scaled aerosol sampler systems are tested in a small wind tunnel while exposed to relatively monodisperse aerosols. Such aerosols are collected by test and reference samplers respectively and assessed gravimetrically. The new studies were carried out for a modified, low flowrate version of the IOM personal inhalable aerosol sampler. It was shown that such experiments can be carried out with a very high level of repeatability, and this supported the general validity of the aerosol sampler scaling laws. The second method involves a novel testing system and protocol for evaluating the performances of aerosol samplers. Here, scaled aerosol samplers of interest are exposed to polydisperse aerosols, again in a small wind tunnel. In this instance, the sampled particles are counted and sized using a direct-reading aerodynamic particle sizer (the APS). A prototype automated aerosol sampler testing system based on this approach was built and evaluated in preliminary experiments to determine the performance of another modified version of the IOM personal inhalable aerosol sampler. The design of the new test system accounts for the complex fluid mechanical coupling that occurs near the sampler inlet involving the transition between the external flow outside the sampler and the internal airflow inside the sampler, leading in turn to uncontrolled particle losses. The problem was overcome by the insertion of porous plastic foam plugs. where the penetration characteristics are well understood, into the entries of both the test and the reference samplers. Preliminary experiments with this new system also supported the general validity of the aerosol sampler scaling laws. In addition, they demonstrated high potential that this approach may be applied in a standardised aerosol testing method and protocol.     

Equivalency of a personal dust monitor to the current United States coal mine respirable dust sampler

The United States National Institute for Occupational Safety and Health, through an informal partnership with industry, labor, and the United States Mine Safety and Health Administration, has developed and tested a new instrument known as the Personal Dust Monitor (PDM). The new dust monitor is an integral part of the cap lamp that coal miners normally carry to work and provides continuous information about the concentration of respirable coal mine dust within the breathing zone of that individual. Previous laboratory testing demonstrated that there is a 95% confidence that greater than 95% of individual PDM measurements fall within +/-25% of reference measurements. The work presented in this paper focuses on the relationship between the PDM and respirable dust concentrations currently measured by a coal mine dust personal sampler unit utilizing a 10 mm Dorr-Oliver nylon cyclone. The United Kingdom Mining Research Establishment instrument, used as the basis for coal mine respirable dust standards, had been designed specifically to match the United Kingdom British Medical Research Council (BMRC) criterion. The personal sampler is used with a 1.38 multiplier to convert readings to the BMRC criterion. A stratified random sampling design incorporating a proportionate allocation strategy was used to select a sample of mechanized mining units representative of all US underground coal mines. A sample of 180 mechanized mining units was chosen, representing approximately 20% of the mechanized mining units in production at the time the sample was selected. A total of 129 valid PDM/personal sampler dust sample sets were obtained. A weighted linear regression analysis of this data base shows that, in comparison with the personal sampler, the PDM requires a mass equivalency conversion multiplier of 1.05 [95% C.I.=(1.03, 1.08)] when the small intercept term is removed from the analysis. Removal of the intercept term results in a personal sampler-equivalent concentration increase of 2.9% at a PDM measurement of 2.0 mg m(-3).     

A comparison of X-ray fluorescence and wet chemical analysis for lead on air filters from different personal samplers used in a bronze foundry

Portable X-ray fluorescence (XRF) technology may provide faster turn-around without compromising accuracy when assessing personal exposures to metals such as lead, but it has only been tested in limited field environments. This study is part of a series, where different sampler types are used to collect airborne lead in different environments for presentation to a portable XRF analyzer. In this case personal samples were taken at a bronze foundry where lead is added to an alloy of copper, zinc and iron to improve casting, using the closed-face 37 mm cassette, the 37 mm GSP or "cone" sampler, the 25 mm Institute of Occupational Medicine (IOM) inhalable sampler, the 25 mm Button sampler, and the open-face 25 mm cassette. Mixed cellulose-ester filters were used in all samplers. Following XRF analysis the samples were extracted with acid and analyzed by inductively coupled plasma optical emission spectroscopy (ICP). For lead, all five samplers gave correlations (r(2)) greater than 0.9 between the two analytical methods over the entire range of found lead mass, which encompassed both the action level and the permissible exposure limit enforced in the USA by the Occupational Safety and Health Administration (OSHA). However, a correction was required to adjust linear regression trendlines to give a 1 : 1 correlation for the average of three readings across the GSP sampler, and a similar correction was required for the single readings from the IOM sampler and the 25 mm filter cassette. The bias possibly is due to interference from other metals, possibly copper which can absorb the fluorescent radiation of lead. In the case of the Button sampler, the bias is larger, indicating a further source of error, perhaps due to the thickness of the deposit. However, in all cases, correction of the lead results did not greatly affect the overall percentage of samples where the XRF result was within 25% of the ICP result, although it did improve the overall accuracy of the results. The GSP, IOM and Button samplers are suitable candidates for further evaluation as compatible with on-site XRF analysis for lead and other metals. It is important to check carefully factory pre-set instrument calibrations, as a bias in the calibration for copper was observed.     

A Passive Sampler for Monitoring Urban Particulate: Preliminary Results

A passive sampling device, developed for personal monitoring of airborne dust levels in industry, has been tested as a site sampler in the urban environment. The device weighs approximately 15g and the essential sampling element is a small disc of electret material (polymer carrying a permanent electric charge). During use it captures particles by electrical attraction, at a rate that depends upon their electrical mobility, but which is independent of the rate at which air flows past the sampler. It collects measurable quantities of particulate, though the sample size tends to be small and correlation with results from conventional samples has not yet been established. Samplers have been exposed to urban particulate for periods of up to seven days, without the electret suffering unacceptable loss of electric charge. It has been shown to be potentially useful for long-term monitoring, a situation in which dispensing with a power source is particularly useful. Being small, the passive sampler is easy to hide or camouflage. It has potential for multiple simultaneous site sampling and for monitoring personal environmental exposure.     

Evaluation of the respicon as a personal inhalable sampler in industrial environments

The Respicon has been introduced as a sampler for health related measurements of airborne contaminants at workplaces. The instrument is aimed at simultaneous collection of three health related aerosol fractions: (a) the coarser inhalable fraction, defining the aerosol fraction that may enter the nose and mouth during breathing; (b) the intermediate thoracic fraction, defining the fraction that may penetrate beyond the larynx and so reach the lung; and (c) the finer respirable fraction, defining the fraction that may penetrate to gas exchange region of the lung. The instrument has a number of features attractive to occupational hygienists: in addition to providing the three aerosol fractions simultaneously, it is light and compact enough to be used as a personal sampler. yet can be a tripod mounted for area sampling, it can provide samples not only for gravimetric analysis but also microscopic and chemical analyses; and it is also available in a photometric direct-reading version. The instrument has previously been evaluated as an area sampler and, in this mode of operation, has shown reasonable accuracy in collecting respirable, thoracic and inhalable particles, the latter up to particle diameters of ca. 80 microm. Except for some scattered unpublished data there exist no systematic investigations in the Respicon's performance when used as a personal sampler in the industrial environment. In this paper, we will report on a study of side by side comparison of the Respicon with the IOM inhalable sampler, regarded as a reference instrument for the inhalable fraction. The main study was performed at six different workplaces in a nickel refinery. Statistical analysis of the gravimetrically-determined concentration data reveals consistently lower aerosol exposure values for the Respicon as compared to the IOM sampler. The data for the nickel workplaces are compared with findings from other studies. The results are interpreted in the light of the overall results and the possibility of introducing a correction factor is discussed.     

Bioaerosol sampling by a personal rotating cup sampler CIP 10-M

High concentrations of bioaerosols containing bacterial, fungal and biotoxinic matter are encountered in many workplaces, e.g. solid waste treatment plants, waste water treatment plants and sewage networks. A personal bioaerosol sampler, the CIP 10-M (M-microbiologic), has been developed to measure worker exposure to airborne biological agents. This sampler is battery operated; it is light and easy to wear and offers full work shift autonomy. It can sample much higher concentrations than biological impactors and limits the mechanical stress on the microorganisms. Biological particles are collected in 2 ml of liquid medium inside a rotating cup fitted with radial vanes to maintain an air flow rate of 10 l min(-1) at a rotational speed of approximately 7,000 rpm. The rotating cup is made of sterilisable material. The sampled particles follow a helicoidal trajectory as they are pushed to the surface of the liquid by centrifugal force, which creates a thin vertical liquid layer. Sterile water or another collecting liquid can be used. Three particle size selectors allow health-related aerosol fractions to be sampled according to international conventions. The sampled microbiological particles can be easily recovered for counting, incubation or further biochemical analysis, e.g., for airborne endotoxins. Its physical sampling efficiency was laboratory tested and field trials were carried out in industrial waste management conditions. The results indicate satisfactory collection efficiency, whilst experimental application has demonstrated the usefulness of the CIP 10-M personal sampler for individual bioaerosol exposure monitoring.