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1、BRITISH STANDARD BS 7789:1995 Guide to Design of measurement laboratories UDC 621.317.2:72.011.1 Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 10:57:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7789:1995 This British Standard, having been prepared under th
2、e direction of the Management Systems Sector Board, was published under the authority of the Standards Board and comes into effect on 15 March 1995 BSI 03-1999 The following BSI references relate to the work on this standard: Committee reference QMS/24 Draft for comment 93/409152 DC ISBN 0 580 23693
3、 5 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Management Systems Sector Board to Technical Committee QMS/24, upon which the following bodies were represented: Association of Consulting Scientists British Gas plc British Steel Indust
4、ry Consumers Association County Surveyors Society Department of Trade and Industry (National Engineering Laboratory) Department of Trade and Industry (National Measurement Accreditation Service) Department of Trade and Industry (National Physical Laboratory) Department of Trade and Industry (Nationa
5、l Weights and Measures Laboratory) Federation of Small Businesses FEI (Federation of the Electronics Industry) GAMBICA (BEAMA Ltd.) Guildford County College of Technology Institute of Measurement and Control Institute of Physics Institute of Quality Assurance Institution of Electrical Engineers Inst
6、itution of Mechanical Engineers Ministry of Defence Society of British Aerospace Companies Limited Amendments issued since publication Amd. No.DateComments Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 10:57:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 778
7、9:1995 BSI 03-1999i Contents Page Committees responsibleInside front cover Forewordii 1Scope1 2References1 3Definitions1 4General considerations and operating conditions1 5Selection of site and design criteria2 6Furniture8 7Receipt and dispatch areas8 8Safety8 9Acceptance tests9 Annex A (normative)
8、Additional considerations for electrical measurement laboratories10 Annex B (normative) Additional considerations for mechanical measurement laboratories11 Annex C (normative) Additional considerations for mass measurement laboratories12 Annex D (informative) Bibliography14 Table 1 Laboratory condit
9、ioned atmospheres6 List of referencesInside back cover Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 10:57:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7789:1995 ii BSI 03-1999 Foreword This British Standard has been prepared under the direction of the Man
10、agement Systems Sector Board. It is intended to provide guidance to those who may be involved in the design, construction, supply, purchase and use of laboratories, or modification of an existing laboratory, in which measurements will be carried out. Measurements can be complex, and can involve a wi
11、de range of technologies and requirements. Measurements are undertaken across an extremely wide field of applications, under differing environmental conditions, and it is likely that other criteria need to be considered for some laboratories, in addition to those given in this standard. It is, howev
12、er, not possible within this guide to cover the design requirements for every type of laboratory. More specialized features for some specific types of laboratory are covered in Annex A, Annex B and Annex C. Other publications giving guidance on laboratory design are listed in the bibliography in Ann
13、ex D. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comp
14、rises a front cover, an inside front cover, pages i and ii, pages 1 to 14, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: Lond
15、on South Bank University, London South Bank University, Fri Dec 08 10:57:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7789:1995 BSI 03-19991 1 Scope This British Standard gives guidance on design criteria and considerations for the siting, construction, environment, supply of services and equipp
16、ing of measurement laboratories, to ensure that measurements undertaken therein are valid and not adversely affected by environmental conditions. Guidance on acceptance tests is also given. This British Standard does not cover the selection, installation or use of measuring instruments. 2 References
17、 2.1 Normative references This British Standard incorporates, by dated and undated reference, provisions from other publications. These normative references are made at the appropriate places in the text and the cited publications are listed on page 16. For dated references, only the edition cited a
18、pplies; any subsequent amendments to or revisions of the cited publication apply to this British Standard only when incorporated in the reference by amendment or revision. For undated references, the latest edition of the cited publication applies, together with any amendments. 2.2 Informative refer
19、ences This British Standard refers to other publications that provide information or guidance. Editions of these publications, current at the time of issue of this standard are listed on page 16, but reference should be made to the latest editions. 3 Definitions For the purposes of this British Stan
20、dard, the definitions given in BS 5233:1986 apply together with the following. 3.1 measurement the set of operations having the object of determining the value of a quantity NOTEThis definition is identical with 2.01 of BS 5233:1986. 3.2 measurand particular quantity subject to measurement Example:
21、vapour pressure of a given sample of water at 20 C NOTE 1The specification of a measurand may require statements about quantities such as time, temperature and pressure. NOTE 2This definition is identical with 2.6 of PD 6461-1:1995 (which is identical with the International vocabulary of basic and g
22、eneral terms in metrology, ISO 1993). 3.3 influence quantity a quantity which is not the subject of the measurement but which influences the value of the measurand or the indication of the measuring instrument Examples: ambient temperature; frequency of an alternating measured voltage NOTEThis defin
23、ition is identical with 2.10 of BS 5233:1986. 3.4 measurement laboratory place where measurements are carried out under controlled conditions 3.5 laboratory conditioned atmosphere specified operating ranges of temperature and relative humidity within which the atmosphere of a measurement laboratory
24、is controlled 3.6 reference conditions conditions of use prescribed for testing the performance of a measuring instrument or for intercomparison of results of measurements NOTEThis definition is similar to 5.07 of BS 5233:1986. 3.7 stability ability of a measuring instrument to maintain constant its
25、 metrological characteristics with time NOTEThis definition is similar to 5.16 of BS 5233:1986. 4 General considerations and operating conditions 4.1 The laboratory environment can influence the results of certain types of measurement. It may therefore be necessary to control influence quantities to
26、 ensure that the desired accuracy of measurements is achieved, and that the results of measurements are within the stated uncertainty. It is also necessary to ensure that the laboratory equipment and processes are not adversely affected by their environment and that the laboratory provides comfortab
27、le working conditions for personnel. The detailed construction of a laboratory needs to vary according to its intended purpose and this should be agreed between the purchaser or user of the laboratory and the supplier. Licensed Copy: London South Bank University, London South Bank University, Fri De
28、c 08 10:57:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7789:1995 2 BSI 03-1999 For most measurement laboratories it is essential that the laboratory environment is controlled to maintain stable conditions, particularly over specified periods of time. A single specified standard atmosphere used
29、by all laboratories would be the ideal but, because of the diversity of climates and measurement requirements, this is not possible (see 5.10.3). A laboratory, either in a new building or in an existing one, usually requires a specification. The requirements and the tests for acceptance of the compl
30、eted laboratory should be clearly and fully specified. Where plant to control the laboratory environment is required, its design should take account of the specified laboratory conditions, the construction of the building, the likely external ambient conditions and working conditions within the labo
31、ratory. It is essential that the plant designer is provided with all the details of the relevant factors that could affect the laboratory environment. In practice it is not possible to test the performance of a laboratory under a wide range of external ambient conditions within a short period, as it
32、 is necessary to depend upon seasonal variations of the external environment. It is essential that a schedule of tests, to be carried out for accepting the completed laboratory, should be prepared and agreed between the supplier and the purchaser or user, as part of the laboratory specification. Rel
33、evant tests should be carried out over a specified and extended period to cover seasonal variations. More detailed recommendations on testing are given in clause 9. 4.2 The basic criteria for siting, construction or modification, environmental conditions, supply of services and furniture apply to th
34、e majority of measurement laboratories. The following major factors should be considered: a) the external and the required internal atmospheric conditions; b) the rate of air change required; c) the nature, accuracy and uncertainty of the measurements to be undertaken; d) the ambient noise and vibra
35、tion; e) any electromagnetic or radiation effects; f) health and safety. It is these factors that mainly dictate the constructional features of the laboratory and the required capacity of any air conditioning plant. 4.3 Other environmental features that need to be considered are illumination (both g
36、eneral and at working positions), operator comfort, air pressure and air pollution. 4.4 Measurement techniques are continually advancing, along with demands for higher accuracies, so when considering a new laboratory the design should allow for future modification to provide flexibility of operation
37、s and possibly later expansion and improvements. 4.5 It is recommended that the management of the design of a measurement laboratory should follow the guidance given in BS 7000-1:1989 and that particular regard should be given to section 3 of that standard. 5 Selection of site and design criteria 5.
38、1 General The site for a laboratory should be chosen with considerable care, paying particular attention to the nature and accuracy of the measurements to be undertaken and any local conditions that could affect the constructional and operational aspects. The factors given in 5.2 to 5.12 should be c
39、onsidered during the planning and design stages since they could affect the operational performance of the laboratory. These criteria are not universally applicable however, and for specialized laboratories more exacting environmental controls, and additional features and services may need to be inc
40、orporated. Additional considerations for some specific types of laboratories are covered in Annex A, Annex B and Annex C as follows: a) Annex A: electrical measurement laboratories; b) Annex B: mechanical measurement laboratories; c) Annex C: mass measurement laboratories. 5.2 Noise and vibration Me
41、asurements and the laboratory personnel can be adversely affected by ambient noise and vibration from the laboratory building and from adjacent buildings, machinery, nearby roads carrying heavy vehicles, railways and other local industrial activities. Ideally, the site for the laboratory should be f
42、ree from such influences, particularly in the case of laboratories making acoustic, optical and mass measurements. If noise and vibration are likely to affect the measurement results, a survey of the site should be carried out to establish both the levels and frequencies of the ambient noise and vib
43、ration. If excessive noise and/or vibration are found, consideration should be given to a more suitable location for the laboratory. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 10:57:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7789:1995 BSI 03-19993 Whe
44、re the vibration level is tolerable, but would be likely to affect the measurement results adversely, the incorporation of damping features and devices within the laboratory structure should be considered. If the vibration level is likely to affect only a few equipments, it may be acceptable to prov
45、ide such equipments with individual anti-vibration mounts. Sources of noise and vibration such as air conditioning plant and power transformers should be installed, as far as practicable, so that the levels of noise and vibration that they generate are minimized. 5.3 Acoustics The ambient noise with
46、in the laboratory should not exceed 50 dBA, with equipment operating but without personnel present. 5.4 Building location and access The on-site roads should be of adequate size and strength to provide easy access for the equipment being delivered to the laboratory. When necessary the building shoul
47、d be located so that it has good connections to a major roadway and rail system. Where large or heavy equipment needs to be handled, an outside area and lifting facilities may be required for loading and unloading vehicles. Adjacent parking for a mobile measurement laboratory may also be needed. 5.5
48、 Building aspect The building aspect of the laboratory, e.g. north facing, should be considered to reduce influences such as sunlight. A considerable amount of heat transmission occurs through external windows. If a laboratory without windows is unacceptable, to reduce heat gains from solar radiatio
49、n in the summer, windows should be fitted only in north facing walls, where practicable. 5.6 Glazing External glazed areas should be kept to a minimum and the fitting of skylights for natural lighting is not recommended for the reasons given in 5.5. Where windows have to be installed they should be multiply-glazed units and fitted with blinds or shades to reduce direct sunlight. Solar control film applied to windows can be beneficial. Internal partitions and doors should be single or multiply-glazed depending on the operation and measurement tasks of the laboratory, and should