EN 1093-4:1996+A1:2008

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Sicherheit von Maschinen - Bewertung der Emission von luftgetragenen Gefahrstoffen - Teil 4: Erfassungsgrad eines Absaugsystems - TracerverfahrenSécurité des machines -Evaluation de l'émission de substances dangereuses véhiculées par l'air - Partie 4 : Efficacité de captage d'un système d'aspiration - Méthode par traçageSafety of machinery - Evaluation of the emission of airborne hazardous substances - Part 4: Capture efficiency of an exhaust system - Tracer method13.110Varnost strojevSafety of machinery13.040.40Stationary source emissionsICS:Ta slovenski standard je istoveten z:EN 1093-4:1996+A1:2008SIST EN 1093-4:1998+A1:2008en,fr,de01-oktober-2008SIST EN 1093-4:1998+A1:2008SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 1093-4:1996+A1
June 2008 ICS 13.040.40 Supersedes EN 1093-4:1996 English Version
Safety of machinery - Evaluation of the emission of airborne hazardous substances - Part 4: Capture efficiency of an exhaust system - Tracer method
Sécurité des machines -Evaluation de l'émission de substances dangereuses véhiculées par l'air - Partie 4 : Efficacité de captage d'un système d'aspiration - Méthode par traçage
Sicherheit von Maschinen - Bewertung der Emission von luftgetragenen Gefahrstoffen - Teil 4: Erfassungsgrad eines Absaugsystems - Tracerverfahren This European Standard was approved by CEN on 10 February 1996 and includes Amendment 1 approved by CEN on 14 May 2008.
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 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 Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
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B-1050 Brussels © 2008 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1093-4:1996+A1:2008: ESIST EN 1093-4:1998+A1:2008

EN 1093-4:1996 (E) 2 Contents Page Foreword.3 1 Scope.4 2 Normative references.4 3 Terms and definitions.4 4 Principle.5 5 Simplified expression of the capture efficiency.5 6 Test method.6 6.1 General procedure.6 6.2 Measurement of the concentration (C3).8 6.3 Application to a specific group of machines.9 7 Control parameters and influencing factors.9 7.1 Control parameters.9 7.2 Influencing factors on capture efficiency.11 8 Test report.11 Annex A (informative)
Simplified calculation of the random component of the uncertainty on C3 (95 %).13 Annex ZA (informative)
!Relationship between this European Standard and the Essential Requirements of EU Directive 98/37/EC"""".14 Annex ZB (informative)
!Relationship between this European Standard and the Essential Requirements of EU Directive 2006/42/EC"""".15
EN 1093-4:1996 (E) 3 Foreword This document (EN 1093-4:1996+A1:2008) has been prepared by Technical Committee CEN/TC 114 “Safety of Machinery”, 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 December 2008, and conflicting national standards shall be withdrawn at the latest by December 2008. This document includes Amendment 1, approved by CEN on 2008-05-14. This document supersedes EN 1093-4:1996. The start and finish of text introduced or altered by amendment is indicated in the text by tags ! ". This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). !For relationship with EU Directive(s), see informative Annexes ZA and ZB, which are integral parts of this document." 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, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. SIST EN 1093-4:1998+A1:2008

EN 1093-4:1996 (E) 4
1 Scope This standard describes a method for the measurement of the capture efficiency of an exhaust system installed on a machine. This method is based on a tracer technique and may be operated in all types of test environment (bench, room and field, see ENV 1093-1). This technique is applicable only if the tracer shows aerodynamic behaviour comparable with the real pollutant (see 7.1.1). The measurement of the capture efficiency of an exhaust system can serve for: a) The evaluation of the performance of an exhaust system of a machine; b) The evaluation of the improvement of an exhaust system c) The comparison of exhaust systems for machines of similar design; d) The ranking of exhaust systems according to their capture efficiency; e) The determination of the air flow rate of an exhaust system to achieve a given level of capture efficiency; f) The determination of the state of the art of exhaust systems for machines with respect to the capture efficiency, 2 Normative references This European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 292-1, Safety of machinery – Basic concepts - General principles for design – Part 1: Basic terminology, methodology. EN 292-2, Safety of machinery – Basic concepts - General principles for design – Part 2: Technical principles and specifications. ENV 1093-1, Safety of machinery – Evaluation of the emission of airborne hazardous substances – Part 1: Selection of test methods. ISO 4053-1, Measurement of gas flow in conduits – Tracer methods – Part 1: General. 3 Terms and definitions For the purpose of this European Standard the following definitions apply: 3.1 capture efficiency of an exhaust system c the ratio of the mass-flowrate of a specified pollutant directly collected by the exhaust system to the uncontrolled mass-flowrate of this pollutant emitted from the machine SIST EN 1093-4:1998+A1:2008

EN 1093-4:1996 (E) 5 3.2 tracer technique the use of substances with an aerodynamic behaviour comparable to the hazardous substance under consideration and which can be reliably measured 4 Principle The principle of the measurement method consists of: a) Emitting a tracer simulating the aerodynamic behaviour of the real pollutant, with the tracer flow rate (qE); b) Measuring the flow rate (qc) of the tracer collected by the exhaust system. 5 Simplified expression of the capture efficiency The capture efficiency expressed as a percentage is: cη= 100×Ecqq (1) The tracer flow rate (qE) is determined by emitting the tracer at constant flow rate directly into the exhaust duct and by measuring the average tracer concentration in a cross section of the duct then: Eq = )(12CCQ− (2) where: Q is the average air flow rate in the duct during the measurement period of (qE); C1 is the average ambient concentration of the tracer before the measurements (background level); C2 is the average concentration of the tracer in the duct (emission of tracer in the duct). The tracer flow rate (qc) is determined by emitting the tracer at constant flow rate (qE) at a characteristic point or zone of the emission of the real pollutant (e.g. at the furthest locations in the emission zone from the exhaust system) and by measuring the average concentration of tracer in the same points of the duct: )'('13CCQqc−= (3) where: Q' is the average air flow rate in the duct during the measurement period of (qc); C'1 is the average ambient concentration of the tracer after the background level is stabilised; C3 is the average concentration of the tracer in the duct (emission at a selected location). The capture efficiency is expressed as a percentage as follows: 100)()'('1001213×−−=×=CCQCCQqqEccη (4) SIST EN 1093-4:1998+A1:2008

EN 1093-4:1996 (E) 6 If the exhaust flow rate can be considered as being constant, then Q = Q', and the expression can be simplified:
100'1213×−−=CCCCcη (5) The capture efficiency is then determined by measuring only concentrations in the exhaust duct. 6 Test method 6.1 General procedure The measurement procedure is illustrated by figures 1 and figure 2 shows a typical test record. To measure the concentration by sampling the air in the duct, it is assumed that the tracer is well mixed with the air. In the case of straight ducts the procedures described in ISO 4053-1 shall be used. NOTE Devices can be added to the duct to reduce the mixing length At least three tests shall be performed. SIST EN 1093-4:1998+A1:2008

EN 1093-4:1996 (E) 7
Phases 1 and 4: Measurement without tracer emission
Phase 2: Measurement with tracer emission in the duct
Phase 3: Measurement with tracer emission simulating the real pollutant 1 sampling 2 pump 3 analyser 4 injection 5 tracer gas flow meter 6 tracer gas cylinder (pure or
diluted tracer gas) 7 ambient concentration C1 or C'1 8
concentration C2 9
concentration C3 Figure 1 — Measurement procedure for a simple exhaust system using a tracer gas
EN 1093-4:1996 (E) 8
a) tracer concentration b) time in seconds Figure 2 — Typical test recording
6.2 Measurement of the concentration (C3) Considering an emitter whose flow rate changes suddenly from 0 to (qE), the concentration (C3) rises progressively as a function of time. The curve of variation of (C3) roughly shows two time constants:  the first, relatively small, corresponds to the accumulation of tracer in the volume directly under the influence of the exhaust system;  the second, which is larger, corresponds to the accumulation of tracer in the rest of the room. A part of the tracer, escaping from the zone of direct influence of the exhaust system, is secondarily and indirectly collected over a longer period of time. Since the efficiency of a system is based on the direct collection of the pollutant, the efficiency is defined on the basis of the determination of the value of (C3) corresponding to the first time constant. In practice, and except for very small rooms, the time constant of the room is much larger than the time constant of the of the collection system, so that the measurement may be facilitated by averaging the value of the efficiency over a time interval of a few minutes after obtaining the first quasi equilibrium state. In small rooms an increase in the ambient concentration can impair the quality of the measurement. For this reason, the measurement should only be accepted if the ratio 1211'CCCC−− is lower than 0,05. The concentration C'1 should be measured 1 minute after dosing of the tracer is stopped. Because of the fluctuations in the response, as can be observed in figure 2, the concentration C3 should be established as an average over a reasonable period of time. For a given measurement, the effective averaging period can be calculated as the time constant for the measuring system multiplied by the number of SIST EN 1093-4:1998+A1:2008

EN 1093-4:1996 (E) 9 samples taken. To allow statistical analyses of the signal, leading to results such as minimum capture efficiency or relative standard deviation, the time constant of the measuring system should be adjusted to a defined value. This adjustment can be achieved by use of a buffer volume on the sampling line or by use of a digital filter. The time constant should be adjusted to 10 s. The interval between successive samples should be equal to or larger than the time constant for the measuring system in use. Statistical analysis of the signal C3 can dete
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