Determination of burning behaviour of dust layers

This European Standard describes a test method for the determination of the burning behaviour of dust layers under defined initial conditions of air flow, temperature and ignition.
A test result of "burning class 1" with the described method does not mean that a dust cannot be ignited when dispersed in a cloud.
This method is not suitable for use with recognized explosives, like gunpowder and dynamite, explosives which do not require oxygen for combustion, pyrophoric substances, or substances or mixtures of substances which may under some circumstances behave in a similar manner. Expert advice should be called in, when any doubt exists about the existence of hazard due to explosive properties.

Brandverhalten von Staubschichten durch Klassifizierung in Brennklassen

Diese Europäische Norm beschreibt ein Prüfverfahren zur Bestimmung des Brennverhaltens von Staubschichten unter definierten Ausgangsbedingungen bezüglich des Luftstroms, der Temperatur und der Entzündung.
Wenn anhand des beschriebenen Verfahrens die Brennzahl 1 festgestellt wird, bedeutet dies nicht, dass der in Luft aufgewirbelte Staub nicht trotzdem entzündet werden kann.
Dieses Verfahren ist nicht für ausgewiesene Explosivstoffe wie Schwarzpulver und Dynamit, für Explosivstoffe, die keinen Sauerstoff zur Verbrennung benötigen, für pyrophore Substanzen oder für Substanzen bzw. Substanzgemische geeignet, die sich unter bestimmten Umständen ähnlich verhalten können. Bei jeglichen Zweifeln bezüglich der Gefährdung durch explosive Eigenschaften sollte fachmännischer Rat eingeholt werden.

Détermination du comportement lors de la combustion des couches de poussières

La présente norme décrit une méthode d’essai pour la détermination du comportement lors de la combustion des couches de poussières dans des conditions initiales définies de débit d’air, de température et d’inflammation.
Un résultat d’essai correspondant à la « classe de combustion 1 » obtenu avec la méthode décrite ne signifie pas qu’un type de poussières ne peut pas s’enflammer lorsqu’il est dispersé en nuage.
Cette méthode ne convient pas aux explosifs reconnus (comme la poudre à canon et la dynamite), aux explosifs dont la combustion peut s’effectuer sans oxygène, aux substances pyrophoriques, ni aux substances ou mélanges de substances qui peuvent se comporter de façon similaire dans certaines conditions. Il convient de demander l’avis d’un expert en cas de doute sur l’existence d’un danger lié aux propriétés explosives.

Ugotavljanje obnašanja pri gorenju prahu v plasteh

Ta evropski standard opisuje preskusno metodo za ugotavljanje obnašanja plasti prahu pri gorenju pod določenimi začetnimi pogoji glede pretoka zraka, temperature in vžiga.
Testni rezultat »razred gorljivosti 1« pri opisani metodi ne pomeni, da ne prah ne more vžgati, če je razpršen v oblak.
Ta metoda ni primerna za uporabo z znanimi eksplozivi, kot sta smodnik in dinamit, z eksplozivnimi materiali, ki za zgorevanje ne potrebujejo kisika, s pirofornimi snovmi oziroma s snovmi ali mešanicami snovmi, ki lahko v nekaterih okoliščinah delujejo na podoben način. V primeru kakršnega koli dvoma o obstoji nevarnosti zaradi eksplozivnih lastnosti se je treba posvetovati s strokovnjakom.

General Information

Status
Published
Publication Date
10-Jun-2018
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
25-May-2018
Due Date
30-Jul-2018
Completion Date
11-Jun-2018

Buy Standard

Standard
EN 17077:2018
English language
19 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Ugotavljanje obnašanja pri gorenju prahu v plastehBrandverhalten von Staubschichten durch Klassifizierung in BrennklassenDétermination du comportement lors de la combustion des couches de poussièresDetermination of burning behaviour of dust layers13.220.40Sposobnost vžiga in obnašanje materialov in proizvodov pri gorenjuIgnitability and burning behaviour of materials and productsICS:Ta slovenski standard je istoveten z:EN 17077:2018SIST EN 17077:2018en,fr,de01-julij-2018SIST EN 17077:2018SLOVENSKI
STANDARD



SIST EN 17077:2018



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 17077
May
t r s z ICS
s uä t t rä v r English Version
Determination of burning behaviour of dust layers Détermination du comportement lors de la combustion des couches de poussières
Bestimmung des Brandverhaltens von StaubschichtenThis European Standard was approved by CEN on
{ March
t r s zä
egulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterationä Upætoædate lists and bibliographical references concerning such national standards may be obtained on application to the CENæCENELEC Management Centre or to any CEN memberä
translation under the responsibility of a CEN member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN members are the national standards bodies of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Serbiaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Rue de la Science 23,
B-1040 Brussels
9
t r s z CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Membersä Refä Noä EN
s y r y yã t r s z ESIST EN 17077:2018



EN 17077:2018 (E) 2 Contents Page European foreword . 3 Introduction . 4 1 Scope . 5 2 Normative references . 5 3 Terms and definitions . 5 4 Principle of the test method . 6 5 Test equipment . 6 5.1 General . 6 5.2 Test apparatus. 6 5.2.1 Board method . 6 5.2.2 Lütolf apparatus . 7 5.3 Ignition source . 8 6 Characterization of dust sample . 8 7 Test procedure . 9 7.1 General . 9 7.2 Sample preparation . 9 7.2.1 Board method . 9 7.2.2 Lütolf apparatus method . 9 7.3 Ignition procedure . 9 7.4 Evaluation . 9 7.5 Additional tests for melting substances . 11 8 Safety precautions / instructions . 11 9 Test report . 12 Annex A (informative)
Tests at elevated initial temperatures . 14 A.1 Additional equipment. 14 A.2 Additional information in the test-report . 14 Annex B (informative)
Alternative test apparatus . 15 B.1 Principles . 15 B.2 Evaluation of results . 16 Annex C (informative)
Example materials demonstrating behaviour typical of each of the burning classes . 17 Annex ZA (informative)
Relationship between this European Standard and the essential requirements of Directive 2014/34/EU aimed to be covered . 18 Bibliography . 19
SIST EN 17077:2018



EN 17077:2018 (E) 3 European foreword This document (EN 17077:2018) has been prepared by Technical Committee CEN/TC 305 “Potentially explosive atmospheres – Explosion prevention and protection”, 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 November 2018, and conflicting national standards shall be withdrawn at the latest by November 2018. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN not be held responsible for identifying any or all such patent rights. This document 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 2014/34/EU. For relationship with EU Directive, see informative Annex ZA, which is an integral part 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, 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 17077:2018



EN 17077:2018 (E) 4 Introduction This document specifies a method for experimental determination of the burning behaviour of dust layers. The determination of burning behaviour of a dust layer is a screening test required to assess the type and magnitude of the fire risk associated with the dust. The determination of the burning behaviour enables assessment of whether a material layer, when in contact with an external ignition source shows a reaction (e.g. ignition, smouldering). It also measures the ability of the locally induced reaction to propagate through the material in bulk or layer form. The behaviour in the test is characterized as a class number (burning class). The burning class allows qualitative estimations on the burning behaviour of a dust layer as well as on the probability of transfer of glowing particles and glowing nests from upstream connected parts of a plant. It is therefore in certain cases a basis for explosion prevention and protection measures. In addition to that the burning class is used as basis to decide whether fire prevention and protection measures are necessary. Therefore this document gives added values to the following clauses of the EU directives: Directive 2014/34/EU of the European Parliament and the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to equipment and protective systems intended for use in potentially explosive atmospheres. The burning behaviour can be markedly affected by physical characteristics (e.g. particle size, packing density) and external factors (e.g. temperature, air movement across the surface of the dust). To obtain comparable and reliable results, it is necessary to standardize the conditions under which the burning behaviour is measured. Further testing may be required for those substances which melt or for which rapid propagation of the combustion reaction is observed in the initial test. If additional information is requested for labelling of the substances according to Regulation (EC) No 1272/2008 (i.e. whether labelling as H228: flammable solid is appropriate) and if testing according to this standard leads to a determination of burning class 4 or 5, then further testing according to the UN (United Nations) Manual of Tests and criteria test N.1 [3] is required. SIST EN 17077:2018



EN 17077:2018 (E) 5 1 Scope This European Standard describes a test method for the determination of the burning behaviour of dust layers under defined initial conditions of air flow, temperature and ignition. A test result of “burning class 1” with the described method does not mean that a dust cannot be ignited when dispersed in a cloud. This method is not suitable for use with recognized explosives, like gunpowder and dynamite, explosives which do not require atmospheric oxygen for combustion, pyrophoric substances, or substances or mixtures of substances which may under some circumstances behave in a similar manner. Expert advice should be called in, when any doubt exists about the existence of hazard due to explosive properties. 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1127-1:2011, Explosive atmospheres — Explosion prevention and protection — Part 1: Basic concepts and methodology EN 13237:2012, Potentially explosive atmospheres — Terms and definitions for equipment and protective systems intended for use in potentially explosive atmospheres 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 13237, EN 1127-1 and the following apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses:
IEC Electropedia: available at http://www.electropedia.org/
ISO Online browsing platform: available at http://www.iso.org/obp 3.1 air flow velocity volume of air [m3] which flows through a defined surface [m2] per unit time [s] 3.2 combustion exothermic reaction with either flames, glowing or smouldering when ignited Note to entry: For the purpose of this standard “combustion” includes decomposition 3.3 ignition initiation of combustion 3.4 initial temperature temperature of the dust train at the moment of ignition SIST EN 17077:2018



EN 17077:2018 (E) 6 3.5 propagation movement of the combustion front along the train 3.6 glowing combustion with light emission without visible flame 3.7 smouldering combustion without light emission 4 Principle of the test method A representative sample of the test substance is placed at ambient temperature on a heat insulating surface and ignition is attempted. The air flow moving along the length of the dust train is kept constant during the test. Since the test result may depend on the temperature of the dust sample tests at elevated temperatures could be necessary (see Annex A). For melting substances the sample preparation or test equipment shall be modified (see 7.5). 5 Test equipment 5.1 General The test apparatus is placed in a laboratory fume cupboard which creates an air flow of approximately 0,2 m/s to 0,4 m/s in the propagation direction of the reaction next to the surface of the dust. The slight overflow with air is necessary, since the sample may produce inert gas after contact with the ignition source. The inert gas can influence the burning behaviour of the dust. NOTE The higher air velocities and/or temperatures present in filter systems or dryers can change the burning behaviour when c
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.