SIST EN 13936:2014
(Main)Workplace exposure - Procedures for measuring a chemical agent present as a mixture of airborne particles and vapour - Requirements and test methods
Workplace exposure - Procedures for measuring a chemical agent present as a mixture of airborne particles and vapour - Requirements and test methods
EN 13936 specifies performance requirements and test methods for the evaluation of procedures for measuring a chemical agent present as a mixture of airborne particles and vapour in workplace air. This European Standard establishes general principles to enable developers and users of mixed-phase samplers and methods to adopt a consistent approach to method validation and provides a framework for the assessment of method performance in accordance with EN 482. Annex A of this European Standard gives guidance on possible approaches to sample mixtures of airborne particles and vapour and Annex B gives information about their physical behaviour. This European Standard is not applicable to methods that differentiate between the sampled airborne particles and vapour. This European Standard is not applicable to a chemical agent present in different chemical and physical forms (for example, mercury in the form of Hg (0) and Hg (II)).
Exposition am Arbeitsplatz - Messung eines als Mischung aus luftgetragenen Partikeln und Dampf vorliegenden chemischen Arbeitsstoffes - Anforderungen und Prüfverfahren
Diese Europäische Norm legt Leistungsanforderungen und Prüfverfahren für die Bewertung von Verfahren zur Messung eines chemischen Arbeitsstoffes fest, der in der Umgebungsluft am Arbeitsplatz als Mischung aus luftgetragenen Partikeln und Dampf vorliegt.
Diese Europäische Norm stellt allgemeine Grundsätze auf, die es den Entwicklern und Anwendern von Sammlern für die Mischphase und von Verfahren ermöglichen, eine einheitliche Herangehensweise bei der Verfahrensvalidierung anzuwenden. Des Weiteren liefert sie einen Rahmen, um die Leistungsfähigkeit des Verfahrens nach EN 482 zu beurteilen.
Diese Europäische Norm enthält außerdem Hinweise zu Verfahrensweisen bei der Probenahme einer Mischung aus luftgetragenen Partikeln und Dampf sowie zu deren Vorteilen und Beschränkungen.
Diese Europäische Norm gilt nicht für Verfahren, die zwischen den als Probe entnommenen luftgetragenen Partikeln und Dampf unterscheiden.
Diese Europäische Norm gilt nicht für einen chemischen Arbeitsstoff, der in unterschiedlichen chemischen und physikalischen Zustandsformen vorliegt (z. B. Quecksilber in Form von Hg (0) und Hg (II)).
Exposition sur les lieux de travail - Mesurage de l'agent chimique sous forme de mélange de particules aériennes et de vapeur - Exigences et méthodes d'essai
La présente Norme européenne spécifie les exigences de performance et les méthodes d’essai pour l’évaluation des procédures de mesure d’un agent chimique présent dans l’air des lieux de travail sous forme d’un mélange de particules en suspension dans l’air et de vapeur.
La présente Norme européenne définit des principes généraux pour permettre aux développeurs et aux utilisateurs de dispositifs de prélèvement et de méthodes applicables aux mélanges de phases d’adopter une approche cohérente de validation de ces méthodes ; elle fournit également un cadre d’évaluation des performances des méthodes conformément à l’EN 482.
La présente Norme européenne fournit également un guide des approches à utiliser pour prélever un mélange de particules en suspension dans l’air et de vapeur, en indiquant aussi leurs avantages et leurs limites.
La présente Norme européenne ne s’applique pas aux méthodes qui différencient le prélèvement de particules en suspension dans l’air et de vapeur.
La présente Norme européenne ne s’applique pas à un agent chimique présent sous différentes formes chimiques et physiques (par exemple, le mercure sous sa forme Hg (0) et sous sa forme Hg (II)).
Izpostavljenost na delovnem mestu - Postopki merjenja kemičnih agensov, prisotnih kot zmesi lebdečih delcev in par - Zahteve in preskusne metode
EN 13936 določa zahteve glede zmogljivosti in preskusne metode za ocenjevanje postopkov merjenja kemičnih agensov, prisotnih kot zmesi lebdečih delcev in hlapov v zraku na delovnem mestu. Ta evropski standard uvaja splošna načela, na podlagi katerih bodo lahko razvijalci in uporabniki raznofaznih vzorčnikov in metod lahko skladno pristopali k potrjevanju metod ter zagotavlja okvir za ocenjevanje zmogljivosti metod v skladu s standardom EN 482. Dodatek A tega evropskega standarda podaja nasvete glede morebitnih pristopov k vzorčnim zmesem lebdečih delcev in hlapov ter Dodatek B zagotavlja informacije glede njihovega fizičnega obnašanja. Ta evropski standard se ne uporablja za metode, ki razlikujejo med vzorčnimi lebdečimi delci in hlapi. Ta evropski standard se ne uporablja za kemične agense, prisotne v drugačnih kemičnih in fizičnih oblikah (na primer živo srebro v obliki Hg (0) in Hg (II)).
General Information
Relations
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.HQVRYExposition am Arbeitsplatz - Messung eines als Mischung aus luftgetragenen Partikeln und Dampf vorliegenden chemischen Arbeitsstoffes - Anforderungen und PrüfverfahrenExposition sur les lieux de travail - Mesurage de l'agent chimique sous forme de mélange de particules aériennes et de vapeur - Exigences et méthodes d'essaiWorkplace exposure - Procedures for measuring a chemical agent present as a mixture of airborne particles and vapour - Requirements and test methods13.040.30Kakovost zraka na delovnem mestuWorkplace atmospheresICS:Ta slovenski standard je istoveten z:EN 13936:2014SIST EN 13936:2014en,fr,de01-julij-2014SIST EN 13936:2014SLOVENSKI
STANDARD
SIST EN 13936:2014
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 13936
January 2014 ICS 13.040.30 English Version
Workplace exposure - Procedures for measuring a chemical agent present as a mixture of airborne particles and vapour - Requirements and test methods
Exposition sur les lieux de travail - Mesurage de l'agent chimique sous forme de mélange de particules aériennes et de vapeur - Exigences et méthodes d'essai
Exposition am Arbeitsplatz - Messung eines als Mischung aus luftgetragenen Partikeln und Dampf vorliegenden chemischen Arbeitsstoffes - Anforderungen und Prüfverfahren This European Standard was approved by CEN on 30 November 2013.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Avenue Marnix 17,
B-1000 Brussels © 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13936:2014 ESIST EN 13936:2014
EN 13936:2014 (E) 2 Contents Page Foreword .4 Introduction .5 1 Scope .6 2 Normative references .6 3 Terms and definitions .6 4 Requirements .7 4.1 General .7 4.2 Sampler requirements .7 4.3 Pumps .7 4.4 Measurement procedure requirements for mixtures of airborne particles and vapour .7 4.4.1 Storage test .7 4.4.2 Expanded uncertainty .7 4.4.3 Method description .7 5 Test methods .8 5.1 Sample distribution between the collection substrate for airborne particles and the collection substrate for vapour .8 5.2 Compliance with EN 1076 .9 5.3 Storage .9 5.4 Uncertainty of the measurement . 10 5.4.1 Calculation of the combined standard uncertainty . 10 5.4.2 Calculation of the expanded uncertainty . 10 6 Test report . 10 Annex A (informative)
Possible approaches to sample mixtures of airborne particles and vapour . 11 A.1 General . 11 A.2 Filter plus pumped sorbent tube . 11 A.2.1 General . 11 A.2.2 Sampling flow rate . 11 A.3 Reagent-impregnated sampling system . 12 A.4 Transport and storage . 12 Annex B (informative)
Physical behaviour of a mixture of airborne particles and vapour . 13 B.1 Generation of a mixture of airborne particles and vapour . 13 B.2 Sampling of chemical agents having a vapour pressure of more than 100 Pa at room temperature (process temperature) . 13 B.3 Sampling of chemical agents having a vapour pressure of more than 0,001 Pa and less than or equal to 100 Pa at room temperature . 13 B.4 Sampling of chemical agents having a vapour pressure of less than 0,001 Pa at room temperature . 15 Annex C (informative)
Estimation of uncertainty of measurement . 16 C.1 Uncertainty components . 16 C.2 Two collection substrates for airborne particles and vapour . 16 SIST EN 13936:2014
EN 13936:2014 (E) 3 C.2.1 Sampled air volume and sampling efficiency. 16 C.2.2 Sample storage . 16 C.2.3 Effects of temperature and humidity . 16 C.2.4 Analysis . 17 C.2.5 Bias of sample distribution between the collection substrate for airborne particles and the collection substrate for vapour (distribution bias) . 17 C.2.6 Calculation of the relative combined uncertainty . 17 C.2.6.1 Samples analysed separately . 17 C.2.6.1.1 General . 17 C.2.6.1.2 Same sampling volume for airborne particles and vapour . 18 C.2.6.1.3 Different sampling volumes for airborne particles and vapour . 18 C.2.6.1.4 Airborne particles or vapour collection substrate not analysed . 19 C.2.6.2 Samples analysed together . 19 C.3 One collection substrate for airborne particles and vapour . 19 C.3.1 General . 19 C.3.2 Sampling. 19 C.3.3 Analysis . 19 C.3.4 Calculation of the relative combined standard uncertainty . 20 Bibliography . 21
SIST EN 13936:2014
EN 13936:2014 (E) 4 Foreword This document (EN 13936:2014) has been prepared by Technical Committee CEN/TC 137 “Assessment of workplace exposure to chemical and biological agents”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by July 2014, and conflicting national standards shall be withdrawn at the latest by July 2014. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 13936:2014
EN 13936:2014 (E) 5 Introduction EN 482 specifies general requirements for the performance of procedures that methods for the measurement of the concentration of chemical agents in workplace atmospheres should meet. These performance criteria include maximum values of expanded uncertainty achievable under prescribed laboratory conditions for the methods to be used. Chemical agents in workplace air are often present in both gaseous and non-gaseous phases at the same time and therefore validated methods are required that can measure the combined concentration of the chemical agent in both phases. Examples include: processes that generate aerosols of volatile or semi-volatile liquids or solids such a paint spraying, metalworking with coolants and lubricants, acid pickling etc. and hot processes which generate vapours of chemical agents that are normally in the liquid or solid phase under ambient conditions, e.g. road surfacing with bitumen. For health-related sampling of mixed-phase aerosols, it is necessary to measure the mass concentration of the inhalable fraction of hazardous chemical agents, regardless of whether they are present as airborne particles or vapour. This generally means drawing air through two or more collection media in series. If a chemical agent is collected in the form of airborne particles and it has a significant vapour pressure under ambient conditions, it will wholly or partly volatilise during sampling. Subsequently the resulting vapour needs to be collected so that the total mass of the chemical agent can be measured; the chemical agent can also be lost from the collected airborne particles after sampling if it is not stabilised. In some cases, it might also be necessary to measure the distribution of chemical agents between the particulate and vapour phases as well as the mass concentration of the inhalable fraction. For example, there can be compounds whose toxicology is known to differ significantly depending on whether they exist as airborne particles or vapour. In addition, control measures in the workplace can depend on which phase dominates. Exposure limits can be phase-specific. However, the separate quantification of airborne particles and vapour is technically complex and subject to error using existing sampling technologies. For this reason, this European Standard is not applicable to methods that differentiate between the sampled airborne particles and vapour. SIST EN 13936:2014
EN 13936:2014 (E) 6 1 Scope This European Standard specifies performance requirements and test methods for the evaluation of procedures for measuring a chemical agent present as a mixture of airborne particles and vapour in workplace air. This European Standard establishes general principles to enable developers and users of mixed-phase samplers and methods to adopt a consistent approach to method validation and provides a framework for the assessment of method performance in accordance with EN 482. Annex A of this European Standard gives guidance on possible approaches to sample mixtures of airborne particles and vapour and Annex B gives information about their physical behaviour. This European Standard is not applicable to methods that differentiate between the sampled airborne particles and vapour. This European Standard is not applicable to a chemical agent present in different chemical and physical forms (for example, mercury in the form of Hg (0) and Hg (II)). 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 481, Workplace atmospheres - Size fraction definitions for measurement of airborne particles EN 482, Workplace exposure - General requirements for the performance of procedures for the measurement of chemical agents EN 1076, Workplace exposure - Procedures for measuring gases and vapours using pumped samplers - Requirements and test methods EN 1540:2011, Workplace exposure - Terminology prEN 13205-11, Workplace exposure — Assessment of sampler performance for measurement of airborne particle concentrations — Part 1: General requirements EN 13890, Workplace exposure - Procedures for measuring metals and metalloids in airborne particles - Requirements and test methods EN ISO 13137, Workplace atmospheres - Pumps for personal sampling of chemical and biological agents - Requirements and test methods (ISO 13137) 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 1540:2011 and the following apply. 3.1 single component aerosol aerosol in which the airborne particles and vapour are composed of the same chemical agent
1) To be published. SIST EN 13936:2014
EN 13936:2014 (E) 7 3.2 multiple component aerosol aerosol containing more than one chemical agent, each of which can be present in the form of airborne particles and/or vapour 3.3 vapour sampler pumped sampler or diffusive sampler that is used to collect vapour 4 Requirements 4.1 General Regardless of the combination of samplers used, the measurement procedure used shall comply with the requirements of EN 482 and with the requirements of EN 1076, EN ISO 13137, prEN 13205-1 and EN 13890, as appropriate. It is the responsibility of the manufacturer or of those who assemble mixed-phase samplers to ensure that the method complies with the requirements for expanded uncertainty under the specified laboratory conditions given in this document, including the environmental influences that can be expected to affect performance. 4.2 Sampler requirements Measurement procedures shall specify the use of a mixed-phase sampler designed to collect the inhalable fraction of airborne particles, as defined in EN 481, and vapours. The sampler shall comply with prEN 13205-1 and with the performance requirements for pumped samplers prescribed in EN 1076. The back pressure of the mixed-phase sampler shall not exceed the maximum values specified in EN ISO 13137. A mixed-phase sampler may comprise of an inhalable sampler in combination with one or more vapour samplers. In such circumstances, the dead volume of the sampling train shall be kept to a minimum and any connection shall be made of an inert material that does not retain the chemical agent of interest. NOTE When a mixed-phase sampler comprises a vapour sampler in combination with an inhalable sampler and there are flow rate compatibility issues, it is possible to split the air flow from the inhalable sampler through more than one vapour sampler. 4.3 Pumps Measurement procedures shall specify the use of pumps complying with EN ISO 13137. 4.4 Measurement procedure requirements for mixtures of airborne particles and vapour 4.4.1 Storage test When tested in accordance with the procedure prescribed in 5.3, the mean analytical recovery after storage shall be at least 90 %. 4.4.2 Expanded uncertainty The expanded uncertainty of the measurement procedure as a whole, including the measurement of airborne particles and vapour, shall comply with the requirements of EN 482. 4.4.3 Method description The method description shall contain at least the following information: SIST EN 13936:2014
EN 13936:2014 (E) 8 a) a general description of the principles of the method, the approach followed to sample mixtures of airborne particles and vapour and any relevant assumptions; b) a detailed description and identification of the system components, including all collection substrates and, for commercial devices, the name of the manufacturer(s) and the product identification(s); c) if applicable, the recommended shelf life of the collection substrate(s); d) the design flow rate and the pressure drop across the mixed-phase sampler at the design flow rate; e) the recommended sampling time and, if applicable, the sampler capacity for a specific analyte; f) methods for handling, transport and storage of samples, including storage times; g) information on analytical methods to be applied and instructions as to whether and how wall deposits are to be included in the analysis of the collected sample; h) the recovery efficiency for specific analytes, including the effects of concentration, loading, temperature and humidity, where applicable; i) any known interference. 5 Test methods 5.1 Sample distribution between the collection substrate for airborne particles and the collection substrate for vapour 5.1.1 Calculate the mass of analyte to be loaded onto the collection substrates in the sample distribution tests for each combination of concentration and time prescribed in Table 1. Table 1 — Concentration and time used for calculation of mass of analyte Reference period Concentration Time long-term 0,1 times limit value 8 h
or recommended sampling time 2 times limit value short-term 1 time limit value e.g. 15 min 5.1.2 Perform sample distribution tests under each of the following two combinations of test conditions: — relative humidity: (50 ± 5) %; — temperature: (10 ± 2) °C and (40 ± 2) °C; — flow rate: recommended flow rate. NOTE One way to obtain air with the required conditions of temperature and relative humidity is to use a climatic test chamber as defined in EN 60068–3–11. 5.1.3 Set up at least six mixed-phase samplers per test and add a known mass of analyte to each collection substrate or, where the mixed-phase sampler includes more than one collection substrate, to each of the first collection substrates. Add the analyte using a micropipette or syringe, if necessary, with the analyte diluted in a non-interfering solvent. 5.1.4 Immediately after adding the analyte, draw air through the mixed-phase samplers under the prescribed test conditions. SIST EN 13936:2014
EN 13936:2014 (E) 9 5.1.5 Repeat 5.1.3 and 5.1.4 for each of the sample loadings calculated in 5.1.1 and under each of the two combinations of test conditions prescribed in 5.1.2. 5.1.6 Analyse each collection substrate immediately after sampling and, for each sampler, calculate the distribution coefficients for vapour and airborne particles according to Formulae (1) and (2): 100pvppd,⋅+=mmmγ (1) pd,vd,100γγ−= (2) where d,p is the distribution coefficient for airborne particles, in percent; d,v is the distribution coefficient for vapour, in percent; mp is the mass determined on the collection substrate for airborne particles, in milligrams; mv is the mass determined on the collection substrate for vapour, in milligrams; Calculate the mean and the coefficient of variation of the replicate samples. Consider the distribution coefficients between the collections substrates used: — if, in all cases, d,p < 10 % the collection substrate for airborne particles does not need to be analysed; — if, in any case 10 % ≤ d,p ≤ 90 % the collection substrates for airborne particles and vapour shall be analysed. — if, in all cases d,p > 90 % only the collection substrate for airborne particles needs to be analysed; 5.2 Compliance with EN 1076 Perform the tests given in EN 1076 using the procedure described in 5.1.3 and 5.1.4 except for the storage test (see 5.3). If it is not possible to generate a test atmosphere for a mixture of airborne particles and vapour, the best approach is to use the spiking method but with the spike applied to the collection substrate of the inhalable sampler rather than the vapour sampler. The spike should be distributed as even as possible on the collection substrate. 5.3 Storage Perform storage tests on samples that have been stabilised as prescribed in the sampling method and verify that the analytical recovery determined from the combined results from the collection substrate for airborne particles and the collection substrate for vapour meets the requirements of 4.4.1. NOTE For a chemical agent present as a mixture of airborne particles and vapour, sampled airborne particles cannot normally be stored without sample loss unless stabilised. See A.4 and B.3.2. SIST EN 13936:2014
EN 13936:2014 (E) 10 5.4 Uncertainty of the measurement 5.4.1 Calculation of the combined standard uncertainty Calculate the combined standard uncertainty uc taking into account the relevant uncertainty components associated with airborne particles and vapour, according to Annex C. 5.4.2 Calculation of the expanded uncertainty Calculate the expanded uncertainty of the measuring procedure, U, using a coverage factor k = 2, according to Formula (3): c2uU×= (3) 6 Test report The test report shall contain at least the following information: a) detailed description and identification of the sampling system components tested, including all collection substrates and for commercial devices name of manufacturer(s) and product identification(s); b) complete identification of test atmospheres used plus details of independent measuring methods, where used; c) details of the pump(s) used for testing; d) details of analytical methods used for testing; e) determined values for recovery efficiency, blank value, sampler capacity and storage losses; f) statistical analyses of the test results and calculations of expanded uncertainty; g) statement of whether the acceptance criteria are met; h) any unusual features noted during the determinations; i) any operations not included in this European Standard that can have influence on the results; j) the technical justification for omitting any of the tests, if done. SIST EN 13936:2014
EN 13936:2014 (E) 11 Annex A (informative)
Possible approaches to sample mixtures of airborne particles and vapour A.1 General General considerations for the sampling of mixtures of airborne particles and vapour have been reviewed by PEREZ and SODERHOLM (see [1]). Sampling mixtures of airborne particles and vapour require an efficient combination of an airborne particle collector placed in series with a vapour collector. According to EN 481, the aspiration characteristics of system inlets are required to follow the inhalable sampling convention. This limits the design flow rate of the devices and their inlet geometry. In general, it will not be possible to quantify the distribution of (airborne) particle and vapour components separately at the moment of sampling, unless specific conditions are met, e.g. the particle component is non-volatile. For the sampling of mixtures of airborne particles and vapour, filter plus pumped sorbent tube (see A.2) and reagent-impregnated systems (see A.3) are most commonly used. Other systems, e.g. denuder and filter or impinger and filter, can be used alternatively for specific chemical agents. A.2 Filter plus pumped sorbent tube A.2.1 General A filter is a particle collection substrate which is used in combination with a device that samples the inhalable fraction according to EN 481. A sorbent tube mounted in series is used to sample vapour. This sampling train will require a specified design flow rate that cannot be altered unless it has been demonstrated to meet the performance requirements for inhalable samplers at other flow rates. In general, a sorbent tube requires a lower flow rate in order to meet the performance requirements for pumped sorbent tubes (such as breakthrough volume). To combine the sorbent tube and the inhalable sampler, for example, the flow downstream of the filter can be split in order to achieve the desired value. The flow split can only be maintained without active flow control if the pressure drop across the sorbent tube remains constant during the sampling period. Volatile and semi-volatile compounds (particles) collected on the filter can evaporate when air is drawn through the sampler. Some chemical agents in vapour form can also be adsorbed by the filter or particles collected on the filter. Thus the original separation of the chemical agents between the particle and vapour phases cannot always be preserved, only the sum of particles and vapour can be quantified. A.2.2 Sampling flow rate Inhalable samplers meeting the requirements of EN 481 often operate at flow rates of 2 l „ min−1 or more. This flow rate is higher than for typical pumped sorbent tubes; channelling and therefore loss of sample can occur if these are used outside their recommended flow rate range. Thermal desorption tubes also become very inefficient and lose capacity at over 500 ml „ min−1 (depending on the size of the sorbent tube), which is also the maximum achievable flow rate due to back pressure. To use filter plus pumped sorbent tube at flow rates of 2 l „ min−1 or more, either a longer pumped sorbent tube should be used to counteract the loss of sampling efficiency, or a wider pumped sorbent tube should be used at a more optimal flow velocity, or the flow should be split. SIST EN 13936:2014
EN 13936:2014 (E) 12 NOTE A longer pumped sorbent tube increases the back-pressure, whereas a wider pumped sorbent tubes requires more sorbent. A.3 Reagent-impregnated sampling system Reagent-impregnated sampling systems usually collect airborne particles and vapour on the same sampling medium. This methodology includes coated filters, coated foams, coated sorbent beds and other similar approaches and is only suitable for reactive substances. The type and amount of reagent used in a reagent-impregnated sampling system should be suitable for the intended purpose. The coated substrate is used in an inhalable sampler which has a specified design flow rate that cannot be altered. In order to collect vapour efficiently, in some instances it might be necessary to combine m
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SLOVENSKI STANDARD
oSIST prEN 13936:2012
01-november-2012
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Workplace exposure - Procedures for measuring a chemical agent present as a mixture
of airborne particles and vapour - Requirements and test methods
Exposition am Arbeitsplatz - Messung eines als Mischung aus luftgetragenen Partikeln
und Dampf vorliegenden chemischen Arbeitsstoffes - Anforderungen und Prüfverfahren
Exposition sur les lieux de travail - Mesurage de l'agent chimique sous forme de
mélange de particules aériennes et de vapeur - Exigences et méthodes d'essai
Ta slovenski standard je istoveten z: prEN 13936
ICS:
13.040.30 Kakovost zraka na delovnem Workplace atmospheres
mestu
oSIST prEN 13936:2012 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN 13936:2012
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oSIST prEN 13936:2012
EUROPEAN STANDARD
DRAFT
prEN 13936
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2012
ICS 13.040.30
English Version
Workplace exposure - Procedures for measuring a chemical
agent present as a mixture of airborne particles and vapour -
Requirements and test methods
Exposition sur les lieux de travail - Mesurage de l'agent Exposition am Arbeitsplatz - Messung eines als Mischung
chimique sous forme de mélange de particules aériennes
aus luftgetragenen Partikeln und Dampf vorliegenden
et de vapeurs - Exigences et méthodes d'essai chemischen Arbeitsstoffes - Anforderungen und
Prüfverfahren
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 137.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 13936:2012: E
worldwide for CEN national Members.
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oSIST prEN 13936:2012
prEN 13936:2012 (E)
Contents Page
Foreword .4
Introduction .5
1 Scope .6
2 Normative references .6
3 Terms and definitions .6
4 Requirements .7
4.1 General .7
4.2 Sampler requirements .7
4.2.1 Inhalable sampler.7
4.2.2 Vapour sampler .7
4.2.3 Mixed-phase sampler .7
4.3 Pumps .7
4.4 Measurement procedure requirements for mixtures of airborne particles and vapour .8
4.4.1 Storage test .8
4.4.2 Expanded uncertainty .8
4.4.3 Method description .8
5 Test methods .8
5.1 Sample distribution between the collection substrate for airborne particles and the
collection substrate for vapour .8
5.2 Test for compliance with EN 1076 .9
5.3 Storage test .9
5.4 Uncertainty of the measurement . 10
5.4.1 Calculation of the combined standard uncertainty . 10
5.4.2 Calculation of the expanded uncertainty . 10
6 Test report . 10
Annex A (normative) Possible approaches to sample mixtures of airborne particles and vapour . 11
A.1 General . 11
A.2 Filter plus pumped sorbent tube . 11
A.2.1 General . 11
A.2.2 Sampling flow rate . 11
A.3 Reagent-impregnated systems . 12
A.4 Transportation and storage . 12
Annex B (informative) Physical behaviour of a mixture of airborne particles and vapour . 13
B.1 Generation of a mixture of airborne particles and vapour . 13
B.2 Sampling of chemical agents having a vapour pressure of more than 100 Pa at room
temperature (process temperature) . 13
B.3 Sampling of chemical agents having a vapour pressure of more than 0,001 Pa and less
than or equal to 100 Pa at room temperature . 13
B.4 Sampling of chemical agents having a vapour pressure of less than 0,001 Pa at room
temperature . 14
Annex C (informative) Estimation of uncertainty of measurement . 16
C.1 Uncertainty components . 16
C.2 Two collection substrates for airborne particles and vapour . 16
C.2.1 Sampled air volume and sampling efficiency . 16
C.2.2 Sample storage . 16
C.2.3 Effects of temperature and humidity . 16
C.2.4 Analysis . 17
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C.2.5 Bias of sample distribution between the collection substrate for airborne particles and
the collection substrate for vapour (distribution bias) . 17
C.2.6 Calculation of the relative combined uncertainty . 17
C.3 One collection substrate for airborne particles and vapour . 19
C.3.1 General . 19
C.3.2 Sampling. 19
C.3.3 Analysis . 19
C.3.4 Calculation of the relative combined standard uncertainty . 20
Bibliography . 21
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Foreword
This document (prEN 13936:2012) has been prepared by Technical Committee CEN/TC 137 “Assessment of
workplace exposure to chemical and biological agents”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
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Introduction
EN 482 specifies general requirements for the performance of procedures that methods for the measurement
of the concentration of chemical agents in workplace atmospheres should meet. These performance criteria
include maximum values of expanded uncertainty achievable under prescribed laboratory conditions for the
methods to be used. Chemical agents in workplace air are often present in both gaseous and non-gaseous
phases at the same time and therefore validated methods are required that can measure the combined
concentration of the chemical agent in both phases. Examples include: processes that generate aerosols of
volatile or semi-volatile liquids or solids such a paint spraying, metalworking with coolants and lubricants, acid
pickling etc.; and hot processes as that generates vapours of chemical agents that are normally in the liquid or
solid phase under ambient conditions, e. g. road surfacing with bitumen.
For health-related sampling of mixed-phase aerosols, it is necessary to measure the mass concentration of
the inhalable fraction of hazardous chemical agents, regardless of whether they are present as airborne
particles or vapour. This generally means drawing air through two or more collection media in series. If a
chemical agent is collected in the form of airborne particles and it has a significant vapour pressure under
ambient conditions, it will wholly or partly volatilise during sampling and the resulting vapour needs to be
subsequently collected, in order that the total mass of the chemical agent is measured; similarly, the chemical
agent can also be lost from the collected airborne particles after sampling if it is not stabilised.
In some cases it can also be necessary to measure the distribution of chemical agents between the particulate
and vapour phases as well as the mass concentration of the inhalable fraction. For example, there can be
compounds whose toxicology is known to differ significantly depending on whether they exist as airborne
particles or vapour. In addition, control measures in the workplace can depend on which phase dominates.
Exposure limits can be phase-specific. However the separate quantification of airborne particles and vapour is
technically complex and subject to error using existing sampling technologies. For this reason this European
Standard is not applicable to methods that differentiate between the sampled airborne particles and vapour.
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1 Scope
This European Standard specifies performance requirements and test methods for the evaluation of
procedures for measuring a chemical agent present as a mixture of airborne particles and vapour in workplace
air.
This European Standard establishes general principles to enable developers and users of mixed-phase
samplers and methods to adopt a consistent approach to method validation and provides a framework for the
assessment of method performance in accordance with EN 482.
This European Standard also gives guidance on approaches to sample a mixture of airborne particles and
vapour and their advantages and limitations.
This European Standard is not applicable to methods that differentiate between the sampled airborne particles
and vapour.
This European Standard is not applicable to a chemical agent present in different chemical and physical forms
(for example, mercury in the form of Hg (0) and Hg (II)).
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
EN 481, Workplace atmospheres — Size fraction definitions for measurement of airborne particles.
EN 482, Workplace exposure — General requirements for the performance of procedures for the
measurement of chemical agents.
EN 838, Workplace exposure — Procedures for measuring gases and vapours using diffusive samplers —
Requirements and test methods.
EN 1076:2009, Workplace exposure — Procedures for measuring gases and vapours using pumped samplers
— Requirements and test methods.
1)
EN 1232 , Workplace atmospheres — Pumps for personal sampling of chemical agents — Requirements
and test methods.
EN 1540, Workplace exposure — Terminology.
1)
EN 12919 , Workplace atmospheres — Pumps for the sampling of chemical agents with a volume flow rate of
over 5 l/min — Requirements and test methods.
EN 13205, Workplace atmospheres — Assessment of performance of instruments for measurement of
airborne particle concentrations.
EN 13890, Workplace exposure — Procedures for measuring metals and metalloids in airborne particles –
Requirements and test methods.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 1540 and the following apply.
1)
An International Standard, ISO 13137, is being elaborated which it is foreseen will replace this document.
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3.1
single component aerosol
aerosol in which the airborne particles and vapour are composed of the same chemical agent
3.2
multiple component aerosol
aerosol containing more than one chemical agent, each of which can be present in the form of airborne
particles and/or vapour
3.3
vapour sampler
pumped sampler or diffusive sampler that is used to collect the vapour
4 Requirements
4.1 General
Regardless of the combination of samplers used, the measurement procedure used shall comply with the
requirements of EN 482 and with the requirements of EN 838, EN 1076, EN 1232, EN 12919, EN 13205 and
EN 13890, as appropriate.
It is the responsibility of the manufacturer or of those who assemble mixed-phase samplers to ensure that the
method complies with the requirements for expanded uncertainty under the specified laboratory conditions
given in this document, including the environmental influences that can be expected to affect performance.
4.2 Sampler requirements
4.2.1 Inhalable sampler
Measurement procedures shall specify the use of a sampler designed to collect the inhalable fraction of
airborne particles, as defined in EN 481, and complying with EN 13205. The inhalable sampler shall operate
at a flow rate that is compatible with that of the vapour sampler.
4.2.2 Vapour sampler
Measurement procedures shall specify the use of a pumped sampler or diffusive sampler that complies with
the requirements specified in EN 1076 or EN 838, respectively. The vapour sampler shall be capable of
operating at a flow rate that is compatible with that of the inhalable sampler.
4.2.3 Mixed-phase sampler
The back pressure of the mixed-phase sampler shall not exceed the pump requirements specified in EN 1232
or EN 12919, as appropriate.
When a mixed-phase sampler comprises of an inhalable sampler in combination with one or more vapour
samplers, the dead volume of the sampling train shall be kept to a minimum and any connection shall be
made of an inert material that does not retain the chemical agent of interest.
NOTE When a mixed-phase sampler comprises of a vapour sampler in combination with an inhalable sampler and
there are flow rate compatibility issues, it is possible to split the air flow from the inhalable sampler through more than one
vapour sampler.
4.3 Pumps
Measurement procedures shall specify the use of pumps complying with EN 1232 or EN 12919, as
appropriate.
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4.4 Measurement procedure requirements for mixtures of airborne particles and vapour
4.4.1 Storage test
When tested in accordance with the procedure prescribed in 5.1, the mean analytical recovery after storage
shall be at least 90 %.
4.4.2 Expanded uncertainty
The expanded uncertainty of the measurement procedure as a whole, including the measurement of airborne
particles and vapour, shall comply with the requirements of EN 482.
4.4.3 Method description
The method description shall contain at least the following information:
a) a general description of the principles of the method, the approach followed to sample mixtures of
airborne particles and vapour and any relevant assumptions;
b) a detailed description and identification of the system components, including all collection substrates and,
for commercial devices, the name of the manufacturer(s) and the product identification(s);
c) if applicable, the recommended shelf life of the collection substrate(s);
d) the design flow rate, pressure drop across the mixed-phase sampler at the design flow rate;
e) the recommended sampling time and, if applicable, the sampler capacity for a specific analyte;
f) methods for handling, transportation and storage of samples, including storage times;
g) information on analytical methods to be applied and instructions as to whether and how wall deposits are
to be included in the analysis of the collected sample;
h) the recovery efficiency for specific analytes, including the effects of concentration, loading, temperature
and humidity, where applicable;
i) any known interference.
5 Test methods
5.1 Sample distribution between the collection substrate for airborne particles and the
collection substrate for vapour
Set up at least six mixed-phase samplers and add a known mass of analyte to the collection substrates or,
where the mixed-phase sampler includes more than one collection substrate, to the first collection substrate.
The mass of analyte is calculated from the limit value and the recommended sampling volume. Add the
analyte using a micropipette or syringe, if necessary, with the analyte diluted in a non-interfering solvent.
Repeat for each sample loading.
Immediately after adding the calculated mass of analyte according to Table 1, draw conditioned air through
the mixed-phase samplers under the following test conditions:
relative humidity: (50 ± 5) %;
temperature: (10 ± 2) °C and (40 ± 2) °C;
flow rate: recommended flow rate.
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NOTE One way to obtain air with the required conditions of temperature and relative humidity is to use a climatic test
chamber as defined in EN 60068-3-11.
Table 1 — Concentration and time used for calculation of mass of analyte
Reference period Concentration Time
long-term 0,1 times limit value 8 h
or recommended
2 times limit value
sampling time
short-term 1 time limit value e.g. 15 min
Analyze each collection substrate and, for each substrate, calculate the distribution coefficients for vapour and
airborne particles according to Formulae (1) and (2):
m
p
γ = ⋅100 (1)
d,p
m + m
v p
γ = 100 − γ (2)
d,v d,p
where
γ is the distribution coefficient for airborne particles, in percent;
d,p
γ is the distribution coefficient for vapour, in percent;
d,v
m is the mass determined on the collection substrate for airborne particles, in milligrams;
p
m is the mass determined on the collection substrate for vapour, in milligrams;
v
Calculate the mean and the coefficient of variation of the replicate samples.
Consider the distribution coefficients between the collections substrates used:
if, in all cases, γ < 10 % the collection substrate for airborne particles does not need to be analysed;
d,p
if, in some cases 10 % ≤ γ ≤ 90 % the collection substrates for airborne particles and vapour shall be
d,p
analysed;
if, in all cases γ > 90 % only the collection substrate for airborne particles needs to be analysed.
d,p
Depending on the storage test (see 5.3) a stabilisation procedure can be required afterwards.
5.2 Test for compliance with EN 1076
Perform the tests given in EN 1076:2009, Clause 8 with the mixed-phase sampler as described in 5.1.
5.3 Storage test
Verify that the analytical recovery determined from the combined results from the collection substrate for
airborne particles and the collection substrate for vapour meets the requirements of 4.4.1.
For a chemical agent present as a mixture of airborne particles and vapour, sampled airborne particles cannot
normally be stored for a long period of time without sample loss. They need to be stabilised, e.g. by sample
dissolution immediately after sampling. See A.7.
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5.4 Uncertainty of the measurement
5.4.1 Calculation of the combined standard uncertainty
Calculate the combined standard uncertainty u expressed as a percentage, according to Formula (3)
c
2 2
u = u + u (3)
c
c c
p v
where
u is the combined standard uncertainty associated with sampling and analysis of the airborne
c
p
particles as estimated using the procedure prescribed in EN 13890, and
u is the combined standard uncertainty associated with sampling and analysis of the vapour as
c
v
estimated using the procedure prescribed in EN 1076 or EN 838.
5.4.2 Calculation of the expanded uncertainty
Calculate the expanded uncertainty of the measuring procedure, U, using a coverage factor k = 2, according
to Formula (4):
U = 2 × u (4)
c
6 Test report
The test report shall contain at least the following information:
a) a detailed description and identification of the system components tested, including all collection
substrates and for commercial devices name of manufacturer(s) and product identification(s);
b) complete identification of test atmospheres used plus details of independent measuring methods, where
used;
c) details of the pump(s) used for testing;
d) details of analytical methods used for testing;
e) the determined values for recovery efficiency, blank value, sampler capacity and storage losses;
f) statistical analyses of the test results and calculations of expanded uncertainty;
g) statement of whether the acceptance criteria are met;
h) any unusual features noted during the determinations;
i) any operations not included in this European Standard that can have influence on the results;
j) the technical justification for omitting any of the tests.
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Annex A
(normative)
Possible approaches to sample mixtures of airborne particles and
vapour
A.1 General
General considerations for the sampling of mixtures of airborne particles and vapour have been reviewed by
PEREZ & SODERHOLM (see reference [1]). Sampling mixtures of airborne particles and vapour require an
efficient combination of an airborne particle collector placed either in series or in parallel with a vapour
collector. According to EN 481 the aspiration characteristics of system inlets are required to follow the
inhalable sampling convention. This limits the design flow rate of the devices and their inlet geometry. In
general, it will not be possible to quantify the distribution of (airborne) particle and vapour components
separately at the moment of sampling, unless specific conditions are met, e.g. the particle component is
non-volatile.
NOTE Depending on the type of inhalable sampler used wall losses can become relevant. See reference [2].
For the sampling of mixtures of airborne particles and vapour, filter plus pumped sorbent tube (see A.2) and
reagent-impregnated systems (see A.3) are most commonly used. Other systems, e.g. denuder and filter or
impinger and filter, can be used alternatively for specific chemical agents.
A.2 Filter plus pumped sorbent tube
A.2.1 General
A filter is a particle collection substrate which is used in combination with a device that samples the inhalable
fraction according to EN 481. A sorbent tube mounted in series is used to sample vapour.
This sampling train will require a specified design flow rate that cannot be altered unless it has been
demonstrated to meet the performance requirements for inhalable samplers at other flow rates.
In general, a sorbent tube requires a lower flow rate in order to meet the performance requirements for
pumped sorbent tubes (such as breakthrough volume). To combine the sorbent tube and the inhalable
sampler, for example the flow downstream of the filter can be split in order to achieve the desired value. The
flow split can only be maintained without active flow control if the pressure drop across the sorbent tube
remains constant during the sampling period.
Volatile and semi-volatile compounds (particles) collected on the filter can evaporate when air is drawn
through the sampler. Some chemical agents in vapour form can also be adsorbed by the filter or particles
collected on the filter. Thus the original separation of the chemical agents between the particle and vapour
phases cannot always be preserved, only the sum of particles and vapour can be quantified.
A.2.2 Sampling flow rate
-1
Inhalable samplers meeting the requirements of EN 481 and EN 482 often operate at flow rates of 2 l ⋅ min
or more. This is higher than for typical pumped sorbent tubes, and channelling and loss of sample can occur if
these are used outside their recommended flow rate range.
-1
Thermal desorption tubes also become very inefficient and lose capacity at over 500 ml ⋅ min (depending on
the size of the sorbent tube), which is also the maximum achievable flow rate due to back pressure.
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-1
To use filter plus pumped sorbent tube at flow rates of 2 l ⋅ min o
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