1、IS0 4225 94 m 4851903 O562252 332 I NTE R NAT I O NA L STANDARD NORME I NTE R NAT I O N AL E IS0 4225 Second edition Deuxime dition 199404-0 1 Air quality - General aspects - Vocabulary Qualit de lair - Aspects gnraux - Vocabulaire Reference number Numro de rfrence IS0 4225:1994(E/F) IS0 4225:1994(E
2、/F) Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which
3、 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. IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all m
4、atters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Inter- national Standard requires approval by at least 75 YO of the member bodies casting a vote. International Standard IS0
5、 4225 was prepared by Technical Committee ISOTTC 146, Air quality, Subcommittee SC 4, General aspects. This second edition cancels and replaces the first edition (IS0 4225:1980), of which it constitutes a technical revision. (P IS0 1994 All rights reserved. Unless otherwise specified, no part of thi
6、s publication may be reproduced or utilized in any form or by any means, electronic or mechanical. including photocopying and microfilm, without permission in writing from the publisher. / Droits de reproduction rserves. Sauf prescription diffrente, aucune partie de cette publication ne peut tre rep
7、roduite ni utilise sous quelque forme que ce soit et par aucun procd, lectronique ou mcanique, y compris la photocopie et les microfilms, sans laccord crit de lditeur. International Organization for Standardization Case postale 56 * CH-121 1 Genve 20 - Switzerland Printed in Switzerland / Imprime en
8、 Suisse IS0 4225:1994(E/F) Avant-propos LISO (Organisation internationale de normalisation) est une fdration mondiale dorganismes nationaux de normalisation (comits membres de IISO). Llaboration des Normes internationales est en general con- fie aux comits techniques de IISO. Chaque comit membre int
9、ress par une tude a le droit de faire partie du comit technique cr mainly in the size range less than 200 pm. 3.24 dry adiabatic lapse rate: See 3.53, lapse rate. 3.25 dust: Small solid particles, conventionally taken as those particles below 75pm in diameter, which settle out under their own weight
10、 but which may remain suspended for some time. (See 3.41, NOTE 1 In some languages, other than English, a single term is used for the English terms “dust“ and “grit“, for example, in French, “poussire“. 3.26 effective chimney height: Height used for the purposes of calculating the dispersion of emit
11、ted gases from a chimney, and which differs from the real chimney height by an amount which depends on such factors as the exit velocity, buoyancy effects and wind speed; it may be affected by topography. grit.) 3.27 electrostatic precipitator: Device for removing particles from a gas stream. The ga
12、s is passed between sets of electrodes across which a very high voltage is maintained. The particles are charged, attracted to the highly charged electrodes and de- posited on the electrodes. 3.28 elutriation: Method of separating particles using the difference in settling velocity which may exist b
13、etween the particles when they are suspended in a flowing fluid. 3.29 emission: Discharge of substances into the atmosphere. The point or area from which the discharge takes place is called the “source“. The term is used to describe the discharge and the rate of discharge. The term can also be appli
14、ed to noise, heat, etc. 3.30 emission concentration: Concentration of air pollutant in an emission at its point of discharge. 3.31 emission factor: Expression for the ratio of the rate at which an air pollutant is emitted as a result of some activity, to the rate of that activity. For example: kilog
15、rams of sulfur dioxide emitted per tonne of steel produced. 3.32 emission flux: Emission rate per unit area of the appropriate surface of an emitting source. Q IS0 3.23 gouttelette; vsicule: Petite particule de liquide, de dimension et de densit telles quelle tomberait dans une atmosphre immobile, m
16、ais peut rester en suspension en rgime turbulent; prin- cipalement dans la gamme de dimensions infrieu- res 200 pm. 3.24 gradient sec adiabatique: Voir 3.53, gradient. 3.25 . (voir 3.42, poussiere): Petites particules so I ides, convention ne1 le ment dfi n es com me des particules de diamtre infrie
17、ur 75 pm qui se d- posent sous leffet de leur propre poids, mais qui peuvent rester en suspension quelque temps. (Voir aussi 3.41, grit.) 3.26 hauteur de chemine efficace: Hauteur utilise pour les besoins du calcul de la dispersion des gaz mis, par une chemine, et qui diffre de sa hauteur vraie, dun
18、e quantit dpendant de facteurs tels que la vitesse de sortie, la temprature des gaz, les effets de pousse dArchimde et la vitesse du vent; elle peut tre affecte par la topographie. 3.27 dpoussireur lectrostatique: Dispositif sparant les particules dun coulement de gaz. Le gaz circule entre des group
19、es dlectrodes entre lesquels est maintenue une tension trs leve. Les particules sont charges, prcipites sous leffet de la charge trs leve des lectrodes et dposes sur les lectrodes. 3.28 lutriation: Mthode de sparation des parti- cules utilisant la diffrence de vitesse de sdimenta- tion qui peut exis
20、ter entre les particules en suspen- sion dans un fluide en coulement. 3.29 mission: Rejet de substances dans Iatmo- sphre. Le point ou la surface do le rejet seffectue sappelle la (source). Le terme est utilis pour d- crire le rejet et le dbit de rejet. Ce terme peut ga- lement tre employ pour le br
21、uit, la chaleur, etc. 3.30 concentration de lmission: Concentration de lmission en polluants de lair au point de rejet. 3.31 facteur dmission: Expression du rapport du taux auquel est mis un polluant de lair rsultant dune activit, sur le taux de cette activit. Par exemple: les kilogrammes de dioxyde de soufre mis par tonne dacier produit. 3.32 flux dmission: Dbit dmission par unit daire de la surface approprie de la source met- trice. 4
