1、BRITISH STANDARD BS EN ISO 8996:2004 Ergonomics of the thermal environment Determination of metabolic rate The European Standard EN ISO 8996:2004 has the status of a British Standard ICS 13.180 BS EN ISO 8996:2004 This British Standard was published under the authority of the Standards Policy and St
2、rategy Committee on 31 January 2005 BSI 31 January 2005 ISBN 0 580 45322 7 National foreword This British Standard is the official English language version of EN ISO 8996:2004. It is identical with ISO 8996:2004. It supersedes BS EN 28996:1994 which is withdrawn. The UK participation in its preparat
3、ion was entrusted by Technical Committee PH/9, Applied ergonomics, to Subcommittee PH/9/1, Thermal environments, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which impleme
4、nt international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does
5、not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European
6、committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page, the
7、 EN ISO foreword page, the ISO title page, pages ii to iv, pages 1 to 24, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments EUROPEAN STANDARD NORME EUROPEN
8、NE EUROPISCHE NORM EN ISO 8996 October 2004 ICS 13.180 Supersedes EN 28996:1993 English version Ergonomics of the thermal environment - Determination of metabolic rate (ISO 8996:2004) Ergonomie de lenvironnement thermique - Dtermination du mtabolisme nergtique (ISO 8996:2004) Ergonomie der thermisch
9、en Umgebung - Bestimmung des krpereigenen Energieumsatzes (ISO 8996:2004) This European Standard was approved by CEN on 26 August 2004. 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
10、standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any oth
11、er language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, F
12、rance, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMU
13、NG Management Centre: rue de Stassart, 36 B-1050 Brussels 2004 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 8996:2004: E Foreword This document (EN ISO 8996:2004) has been prepared by Technical Committee ISO/TC 159 “Ergonomi
14、cs“ 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 text or by endorsement, at the latest by April 2005, and conflicting national
15、 standards shall be withdrawn at the latest by April 2005. This document supersedes EN 28996:1993. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republi
16、c, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 8996:2004 has been approved by C
17、EN as EN ISO 8996:2004 without any modifications. ENISO8996:2004 Reference number ISO 8996:2004(E)INTERNATIONAL STANDARD ISO 8996 Second edition 2004-10-01 Ergonomics of the thermal environment Determination of metabolic rate Ergonomie de lenvironnement thermique Dtermination du mtabolisme nergtique
18、 ENISO8996:2004ii ENISO8996:2004 iiiContents Page Foreword iv 1 Scope 1 2 Normative references . 1 3 Principle and accuracy. 1 4 Level 1, screening . 3 4.1 Table for the estimation of metabolic rate by occupation 3 4.2 Classification of metabolic rate by categories 3 5 Level 2, observation 3 5.1 Est
19、imation of metabolic rate by task requirements 3 5.2 Metabolic rate for typical activities . 4 5.3 Metabolic rate for a work cycle 4 5.4 Influence of the length of rest periods and work periods. 5 5.5 Obtaining values by interpolation . 6 5.6 Requirements for the application of metabolic-rate tables
20、 6 6 Level 3, analysis 6 6.1 Estimation of metabolic rate using heart rate 6 6.2 Relationship between heart rate and metabolic rate. 7 7 Level 4, expertise 8 7.1 Determination of metabolic rate by measurement of oxygen consumption rate. 8 7.2 The doubly labelled water method for long-term measuremen
21、ts 14 7.3 Direct calorimetry Principle. 14 Annex A (informative) Evaluation of the metabolic rate at level 1, screening . 15 Annex B (informative) Evaluation of the metabolic rate at level 2, observation 17 Annex C (informative) Evaluation of the metabolic rate at level 3, analysis 20 Annex D (infor
22、mative) Evaluation of the metabolic rate at level 4, expertise Examples of the calculation of metabolic rate based on measured data 21 ENISO8996:2004iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The wo
23、rk 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, governmental and non-governm
24、ental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical 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
25、main task of technical committees is to prepare International Standards. Draft International Standards adopted by 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.
26、Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 8996 was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 5, Ergonomics of
27、 the physical environment. This second edition cancels and replaces the first edition (ISO 8996:1990), which has been technically revised. ENISO8996:2004INTENRATIONAL TSANDADR IS:6998 O4002(E)Ergonomics of the thermal environment Determination of metabolic rate 1 Scope The metabolic rate, as a conve
28、rsion of chemical into mechanical and thermal energy, measures the energetic cost of muscular load and gives a numerical index of activity. Metabolic rate is an important determinant of the comfort or the strain resulting from exposure to a thermal environment. In particular, in hot climates, the hi
29、gh levels of metabolic heat production associated with muscular work aggravate heat stress, as large amounts of heat need to be dissipated, mostly by sweat evaporation. This International Standard specifies different methods for the determination of metabolic rate in the context of ergonomics of the
30、 climatic working environment. It can also be used for other applications for example, the assessment of working practices, the energetic cost of specific jobs or sport activities, the total cost of an activity, etc. The estimations, tables and other data included in this International Standard conc
31、ern an “average” individual: a man 30 years old weighing 70 kg and 1,75 m tall (body surface area 1,8 m 2 ); a woman 30 years old weighing 60 kg and 1,70 m tall (body surface area 1,6 m 2 ). Users should make appropriate corrections when they are dealing with special populations including children,
32、aged persons, people with physical disabilities, etc. 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 (includi
33、ng any amendments) applies. ISO 9886, Ergonomics Evaluation of thermal strain by physiological measurements ISO 15265, Ergonomics of the thermal environment Risk assessment strategy for the prevention of stress or discomfort in thermal working conditions 3 Principle and accuracy The mechanical effic
34、iency of muscular work called the “useful work”, W is low. In most types of industrial work, it is so small (a few percent) that it is assumed to be nil. This means that the total energy consumption while working is assumed equal to the heat production. For the purposes of this International Standar
35、d, the metabolic rate is assumed to be equal to the rate of heat production. Table 1 lists the different approaches presented in this International Standard for determining the metabolic rate. These approaches are structured following the philosophy exposed in ISO 15265 regarding the assessment of e
36、xposure. Four levels are considered here: ENISO8996:20041 Level 1, screening: Two methods simple and easy to use are presented to quickly characterize the mean workload for a given occupation or for a given activity: method 1A is a classification according to occupation; method 1B is a classificatio
37、n according to the kind of activity. Both methods provide only a rough estimate and there is considerable scope for error. This limits their accuracy considerably. At this level, an inspection of the work place is not necessary. Level 2, observation: Two methods are presented for people with full kn
38、owledge of the working conditions but without necessarily a training in ergonomics, to characterize, on average, a working situation at a specific time: in method 2A, the metabolic rate is determined by adding to the baseline metabolic rate the metabolic rate for body posture, the metabolic rate for
39、 the type of work and the metabolic rate for body motion related to work speed (using group assessment tables); in method 2B, the metabolic rate is determined by means of the tabulated values for various activities. A procedure is described to record the activities with time and compute the time-wei
40、ghted average metabolic rate, using the data from the two methods above. The possibility for errors is high. A time and motion study is necessary to determine the metabolic rate in work situations that involve a cycle of different activities. Level 3, analysis: One method is addressed to people trai
41、ned in occupational health and ergonomics of the thermal environment. The metabolic rate is determined from heart rate recordings over a representative period. This method for the indirect determination of metabolic rate is based on the relationship between oxygen uptake and heart rate under defined
42、 conditions. Level 4, expertise: Three methods are presented. They require very specific measurements made by experts: in Method 4A, the oxygen consumption is measured over short periods (10 min to 20 min) (a detailed time and motion study is necessary to show the representativity of the measurement
43、 period); method 4B is the so-called doubly labelled water method aiming at characterizing the average metabolic rate over much longer periods (1 to 2 weeks); method 4C is a direct calorimetry method. The main factors affecting the accuracy of the estimations are the following: individual variabilit
44、y; differences in the work equipment; differences in work speed; differences in work technique and skill; gender differences and anthropometric characteristics; cultural differences; when using the tables, differences between observers and their level of training; ENISO8996:20042ISO 8996:2004(E) I S
45、O 4002 All irthgs ersedevr 3 when using level 3, the accuracy of the relationship between heart rate and oxygen uptake, as other stress factors also influence the heart rate; at level 4, the measurement accuracy (determination of gas volume and oxygen fraction). The accuracy of the results, but also
46、 the costs of the study, increase from level 1 to level 4. Measurement at level 4 gives the most accurate values. As far as possible, the most accurate method should be used. Table 1 Levels for the determination of the metabolic rate Level Method Accuracy Inspection of the work place 1A: Classificat
47、ion according to occupation Not necessary, but information needed on technical equipment, work organization 1 Screening 1B: Classification according to activity Rough information Very great risk of error 2A: Group assessment tables Time and motion study necessary 2 Observation 2B: Tables for specifi
48、c activities High error risk Accuracy: 20 % 3 Analysis Heart rate measurement under defined conditions Medium error risk Accuracy: 10 % Study required to determine a representative period 4A: Measurement of oxygen consumption Time and motion study necessary 4B: Doubly labelled water method Inspectio
49、n of work place not necessary, but leisure activities must be evaluated. 4 Expertise 4C: Direct calorimetry Errors within the limits of the accuracy of the measurement or of the time and motion study Accuracy: 5 % Inspection of work place not necessary 4 Level 1, screening 4.1 Table for the estimation of metabolic rate by occupation Table A.1 in Annex A shows the metabolic rate for different occupations. The
