6184/1 International Standard OS1) INTERNATIONAL ORGANIZATION FOR STANDARDIZATIONMEKAYHAPOAHAR OPIAHM3AUMA NO CTAHAAPTM3AUWM-ORGANISATION INTERNATIONALE DE NORMALISATION Explosion protection systems Part 1 : Determination of explosion indices of combustible dusts in air Systemes de protection contre les explosions - Partie 1: Determination des indices d'explosion des poussieres combustibles dans I'air First edition - 1985-11-15 ISO 6184/1-1985 (E) UDC 614.835 Ref. No. ISO 6184/1-1985 (E) Descriptors : explosion proofing, dust, tests, explosion index. Pricebasedon5pages Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards bodies (iso member bodies). The work of preparing International Standards is normally carried out through Iso technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. They are approved in accordance with ISO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 6184/1 was prepared by Technical Committee ISO/TC 21, Equipment for fire protection and fire fighting. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. ? InternationalOrganizationforStandardization,1985 Printed in Switzerland INTERNATIONAL STANDARD ISO 6184/1-1985 (E) Explosion protection systems Part 1 : Determination of explosion indices of combustible dusts in air 0 Introduction type of hazard is the responsibility of specialists in the fields of explosions and explosion protection. The assessment of measures required to provide protec- tion against explosion hazards involving combustible dust/air Two extremes of turbulence commonly encountered in in- dustrial plants are: mixtures requirespriordeterminationof thepotentialexplosion severity of such mixtures,bythe measurement of explosion (e low turbulence conditions prevailing in a gravity-fed indices. Conversely, the measurement of the effectiveness and silo; performance of explosion protection systems requires that they b) high turbulence conditions prevailing in a grinder or should be tested against explosions of known severity. micronizer. The severity of a dust explosion is a function of the following : It should be realized that turbulence can arise in two ways : a) the physical and chemical properties of the dust; a) turbulence intrinsic to the plant, under normal b) the concentration of dust in the dust/air mixture; operating conditions, as a consequence of perturbations to c) the homogeneity and turbulence of the dust/air mix- the air-flow; ture; b) turbulence induced by obstructions within an installa- tion on a gas which expands as the result of an explosion. (P the type, energy, and location of the ignition source; e) the geometry of the container; 1 Scope f) the temperature, pressure and humidity of the explosive dust/airmixture. This part of iSO 6184 specifies a method for the determination of the explosion indices of combustible dusts suspended in air 0.2 This part of is 6184 is one of a series dealing with ex- in anenclosed space.It givesthe criteriaby which results ob- plosion protection systems. The other parts are as follows: tained using othertest procedures can be correlated to yieldex- Part 2: Determination of explosion indices of combustible part of iso 6184. gases in air. Part 3: Determination of explosion indices of fuel/air mix- 2 Field of application tures other than dust/air and gas/air mixtures. Part 4: Det