EN ISO 11079-2007 en Ergonomics of the thermal environment - Determination and interpretation of cold stress when using required clothing insulation (IREQ) and local cooling effect.pdf

1、BRITISH STANDARDBS EN ISO 11079:2007Ergonomics of the thermal environment Determination and interpretation of cold stress when using required clothing insulation (IREQ) and local cooling effectsICS 13.180g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g

2、3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 11079:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 January 2008 BSI 2008ISBN 978 0 580 54566 5National forewordThis Br

3、itish Standard is the UK implementation of EN ISO 11079:2007. It supersedes DD ENV ISO 11079:1999 which is withdrawn.The UK participation in its preparation was entrusted by Technical Committee PH/9, Applied ergonomics, to Subcommittee PH/9/1, Thermal environments.A list of organizations represented

4、 on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrig

5、enda issued since publicationDate CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 11079December 2007ICS 13.180 Supersedes ENV ISO 11079:1998 English VersionErgonomics of the thermal environment - Determination andinterpretation of cold stress when using required clothinginsulation (IRE

6、Q) and local cooling effects (ISO 11079:2007)Ergonomie des ambiances thermiques - Dtermination etinterprtation de la contrainte lie au froid en utilisantlisolement thermique requis du vtement (IREQ) et leseffets du refroidissement local (ISO 11079:2007)Ergonomie der thermischen Umgebung - Bestimmung

7、 undInterpretation der Kltebelastung bei Verwendung dererforderlichen Isolation der Bekleidung (IREQ) und lokalenKhlwirkungen (ISO 11079:2007)This European Standard was approved by CEN on 14 December 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the c

8、onditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in thr

9、ee official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Aus

10、tria, 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.EUROPEAN COMMIT

11、TEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 11079:2007: EForeword This document (E

12、N ISO 11079:2007) has been prepared by Technical Committee ISO/TC 159 “Ergonomics“ in collaboration with Technical Committee CEN/TC 122 “Ergonomics” 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

13、 text or by endorsement, at the latest by June 2008, and conflicting national standards shall be withdrawn at the latest by June 2008. 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 responsibl

14、e for identifying any or all such patent rights. This document supersedes ENV ISO 11079:1998. 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 Re

15、public, 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 the United Kingdom. Endorsement notice The text of ISO 11079:2007 has

16、 been approved by CEN as a EN ISO 11079:2007 without any modification. BS EN ISO 11079:2007Reference numberISO 11079:2007(E)INTERNATIONAL STANDARD ISO11079First edition2007-12-15Ergonomics of the thermal environment Determination and interpretation of cold stress when using required clothing insulat

17、ion (IREQ) and local cooling effects Ergonomie des ambiances thermiques Dtermination et interprtation de la contrainte lie au froid en utilisant lisolement thermique requis du vtement (IREQ) et les effets du refroidissement local BS EN ISO 11079:2007ii iiiContents Page Foreword iv Introduction v 1 S

18、cope . 1 2 Normative references . 1 3 Terms, definitions and symbols 2 4 Principles of methods for evaluation 4 5 General cooling. 4 6 Local cooling. 10 7 Practical assessment of cold environments and interpretation 11 Annex A (normative) Computation of thermal balance 13 Annex B (informative) Physi

19、ological criteria in cold exposure . 16 Annex C (informative) Metabolic rate and thermal properties of clothing . 18 Annex D (informative) Determination of wind cooling . 21 Annex E (informative) Examples of evaluation of IREQ . 23 Annex F (informative) Computer program for calculating IREQ . 33 Bib

20、liography . 34 BS EN ISO 11079:2007iv 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

21、 interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotec

22、hnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by

23、the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent righ

24、ts. ISO shall not be held responsible for identifying any or all such patent rights. ISO 11079 was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 5, Ergonomics of the physical environment. This first edition of ISO 11079 cancels and replaces the ISO/TR 11079:1993, of which i

25、t constitutes a technical revision. BS EN ISO 11079:2007vIntroduction Wind chill is commonly encountered in cold climates, but it is low temperatures that first of all endanger body heat balance. By proper adjustment of clothing, human beings can often control and regulate body heat loss, to balance

26、 a change in the ambient climate. The method presented here is based therefore on the evaluation of the clothing insulation required to maintain the thermal balance of the body in equilibrium. The heat balance equation used takes into account the most recent scientific findings concerning heat excha

27、nges at the surface of the skin as well as the clothing. BS EN ISO 11079:2007blank1Ergonomics of the thermal environment Determination and interpretation of cold stress when using required clothing insulation (IREQ) and local cooling effects 1 Scope This International Standard specifies methods and

28、strategies for assessing the thermal stress associated with exposure to cold environments. These methods apply to continuous, intermittent as well as occasional exposure and type of work, indoors and outdoors. They are not applicable to specific effects associated with certain meteorological phenome

29、na (e.g. precipitation), which are assessed by other methods. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document

30、(including any amendments) applies. ISO 7726, Ergonomics of the thermal environment Instruments for measuring physical quantities ISO 8996, Ergonomics of the thermal environment Determination of metabolic rate ISO 9237, Textiles Determination of permeability of fabrics to air ISO 9920, Ergonomics of

31、 the thermal environment Estimation of thermal insulation and water vapour resistance of a clothing ensemble ISO 13731, Ergonomics of the thermal environment Vocabulary and symbols ISO 13732-3, Ergonomics of the thermal environment Methods for the assessment of human responses to contact with surfac

32、es Part 3: Cold surfaces ISO 15831, Clothing Physiological effects Measurement of thermal insulation by means of a thermal manikin EN 511, Protective gloves against cold BS EN ISO 11079:20072 3 Terms, definitions and symbols For the purposes of this document, the terms and definitions given in ISO 1

33、3731 and the following terms, definitions and symbols apply. 3.1 Terms and definitions 3.1.1 cold stress climatic conditions under which the body heat exchange is just equal to or too large for heat balance at the expense of significant and sometimes uncompensable physiological strain (heat debt) 3.

34、1.2 heat stress climatic conditions under which the body heat exchange is just equal to or too small for heat balance at the expense of significant and sometimes uncompensable physiological strain (heat storage) 3.1.3 IREQ required clothing insulation for the preservation of body heat balance at def

35、ined levels of physiological strain 3.1.4 thermoneutral zone temperature interval within which the body maintains heat balance exclusively by vasomotor reactions 3.1.5 wind chill temperature temperature related to the cooling effect on a local skin segment 3.2 Symbols ADuDubois body surface area, m2

36、ap air permeability, l m-2 s1C convective heat flow (exchange), W m2cewater latent heat of vaporization, J kg1cpspecific heat of dry air at constant pressure, J kg1 K1Cresrespiratory convective heat flow (loss), W m2Dlimduration limited exposure, h Drecrecovery time, h E evaporative heat flow (excha

37、nge) at the skin, W m2Eresrespiratory evaporative heat flow (loss), W m2fclclothing area factor, dimensionless hcconvective heat transfer coefficient, W m2 K1hrradiative heat transfer coefficient, W m2 K1Iaboundary layer thermal insulation, m2 K W1Ia,rresultant boundary layer thermal insulation, m2

38、K W1BS EN ISO 11079:20073Iclbasic clothing insulation, m2 K W1Icl,rresultant clothing insulation, m2 K W1ITbasic total insulation, m2 K W1IT,rresultant total insulation, m2 K W1immoisture permeability index, dimensionless IREQ required clothing insulation, m2 K W1IREQminminimal required clothing ins

39、ulation, m2 K W1IREQneutralneutral required clothing insulation, m2 K W1K conductive heat flow (exchange), W m2M metabolic rate, W m2pawater vapour partial pressure, kPa pexsaturated water vapour pressure at expired air temperature, kPa pskwater vapour pressure at skin temperature, kPa psk,s saturat

40、ed water vapour pressure at the skin surface, kPa Q body heat gain or loss, kJ m2Qlimlimit value for Q, kJ m2R radiative heat flow (exchange), W m2Re,Ttotal evaporative resistance of clothing and boundary air layer, m2 kPa W1S body heat storage rate, W m2taair temperature, C tclclothing surface temp

41、erature, C texexpired air temperature, C tooperative temperature, C trradiant temperature tsklocal skin temperature, C skt mean skin temperature, C tWCwind chill temperature, C V respiratory ventilation rate, kg air s1v10wind speed measured 10 m above ground level, m s1vaair velocity, m s1vwwalking

42、speed, m s1W effective mechanical power, W m2w skin wettedness, dimensionless BS EN ISO 11079:20074 Wahumidity ratio of inhaled air, kg water/kg dry air Wexhumidity ratio of exhaled air, kg water/kg dry air Stefan-Boltzmann constant clemissivity of clothing surface, dimensionless 4 Principles of met

43、hods for evaluation Cold stress is evaluated in terms of both general cooling of the body and local cooling of particular parts of the body (e.g. extremities and face). The following types of cold stress are identified. a) General cooling For general cooling, an analytical method is presented in Cla

44、use 5 for the evaluation and interpretation of the thermal stress. It is based on a calculation of the body heat exchange, the required clothing insulation (IREQ) for the maintenance of thermal equilibrium and the insulation provided by clothing ensemble in use or anticipated to be used. b) Local co

45、oling 1) convective cooling (wind chill) 2) conductive cooling 3) extremity cooling 4) airway cooling For local cooling, methods are proposed in Clause 6. Criteria and limit values are also given in Clause 6 and Annex B. In the following sections, the main steps of evaluation are described. 5 Genera

46、l cooling 5.1 Overview A general equation for body heat balance is defined. In this equation clothing thermal properties, body heat production and physical characteristics of the environment are the determinant factors. The equation is solved for the required clothing insulation (IREQ) for maintaine

47、d heat balance under specified criteria of physiological strain. IREQ is subsequently compared with the protection (insulation) offered by the workers clothing. If worn insulation is less than required, a duration limited exposure (Dlim) is calculated on the basis of acceptable levels of body coolin

48、g. Detailed formulas, coefficients and criteria are proposed in Annexes A and B. The method involves the following steps, outlined schematically in Figure 1: measurements of the thermal parameters of the environment; determination of activity level (metabolic rate); calculation of IREQ; comparison o

49、f IREQ with resultant insulation provided by clothing in use; evaluation of the conditions for thermal balance and calculation of the recommended maximal exposure time (Dlim). BS EN ISO 11079:20075Figure 1 Procedure for evaluation of cold environments BS EN ISO 11079:20076 5.2 Definition of required clothing insulation, IREQ IREQ is the resultant clothing insulation required in the actual environmental conditions t