DIN EN 16242-2013 Conservation of cultural heritage - Procedures and instruments for measuring humidity in the air and moisture exchanges between air and cultural property German v.pdf

1、March 2013 Translation by DIN-Sprachendienst.English price group 14No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS

2、97.195!$L“1959441www.din.deDDIN EN 16242Conservation of cultural heritage Procedures and instruments for measuring humidity in the air andmoisture exchanges between air and cultural property;English version EN 16242:2012,English translation of DIN EN 16242:2013-03Erhaltung des kulturellen Erbes Verf

3、ahren und Gerte zur Messung der Luftfeuchte und des Austausches vonFeuchtigkeit zwischen Luft und Kulturgut;Englische Fassung EN 16242:2012,Englische bersetzung von DIN EN 16242:2013-03Conservation des biens culturels Modes opratoires et instruments de mesure de lhumidit de lair et des changesdhumid

4、it entre lair et les biens culturels;Version anglaise EN 16242:2012,Traduction anglaise de DIN EN 16242:2013-03www.beuth.deIn case of doubt, the German-language original shall be considered authoritative.Document comprises 31 pages 02.13 DIN EN 16242:2013-03 2 A comma is used as the decimal marker.

5、National foreword This document (EN 16242:2012) has been prepared by Technical Committee CEN/TC 346 “Conservation of cultural property” (Secretariat: UNI, Italy). The responsible German body involved in its preparation was the Normenausschuss Bauwesen (Building and Civil Engineering Standards Commit

6、tee), Working Committee NA 005-01-36 AA Erhaltung des kulturellen Erbes. EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16242 November 2012 ICS 97.195 English Version Conservation of cultural heritage - Procedures and instruments for measuring humidity in the air and moisture exchanges between

7、 air and cultural property Conservation des biens culturels - Modes opratoires et instruments de mesure de lhumidit de lair et des changes dhumidit entre lair et les biens culturels Erhaltung des kulturellen Erbes - Verfahren und Gerte zur Messung der Luftfeuchte und des Austausches von Feuchtigkeit

8、 zwischen Luft und Kulturgut This European Standard was approved by CEN on 8 September 2012. 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 standard without any alteration. Up-to-date

9、 lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation u

10、nder the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Forme

11、r Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT E

12、UROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16242:2012: EEN 16242:2012 (E) 2 Contents Page Foreword . 3 Introducti

13、on 4 1 Scope 5 2 Normative references . 5 3 Terms and definitions 5 4 Quantities characterising humidity in air 8 4.1 General . 8 4.2 Relative humidity . 9 4.3 The humidity mixing ratio 9 4.4 Absolute humidity 9 4.5 Dew-point temperature 9 5 Considerations and recommendations related to measuring me

14、thods 9 5.1 Considerations . 9 5.2 Recommendations . 10 6 Main features of the hygrometers . 11 6.1 Chilled-mirror dew-point hygrometer 11 6.2 Electronic psychrometer 12 6.3 Electronic hygrometer with a capacitive sensor 13 6.4 Electronic hygrometer with a resistive sensor . 13 6.5 Hair hygrometer/h

15、ygrograph . 14 7 Instrument calibration 14 Annex A (informative) Formulae for calculating relative humidity and related variables 16 A.1 Instruments: Psychrometer, barometer Parameters: air temperature t (C), wet bulb air temperature tw(C), p (hPa) . 16 A.2 Instruments: RH hygrometer, thermometer, b

16、arometer - Parameters: t, RH, p . 17 A.3 Instruments: Dew-point hygrometer, thermometer, barometer - Parameters: t,: td, p 18 Annex B (informative) Examples for indoor climate measurements . 19 B.1 Recognising the penetration and spread of external air across a room . 19 B.2 Recognising if wall damp

17、ness is associated to condensation or evaporation . 20 B.3 External dampness entering a room shown with a mixing ratio plot 20 Annex C (informative) Instrumental errors . 22 C.1 Psychrometer: errors in the various hygrometric variables generated by an error of 0,1 C in a temperature reading . 22 C.2

18、 Psychrometer: error in determining the relative humidity due to pressure change . 23 C.3 Error due to a thermal inertia of a case, a probe or a shield 23 C.4 Typical non-linearity and hysteresis of the hair hygrometer . 24 C.4.1 Hair non-linearity and hysteresis 24 C.4.2 Linear and non-linear scale

19、s . 25 Bibliography 28 DIN EN 16242:2013-03 EN 16242:2012 (E) 3 Foreword This document (EN 16242:2012) has been prepared by Technical Committee CEN/TC 346 “Conservation of cultural heritage”, the secretariat of which is held by UNI. This European Standard shall be given the status of a national stan

20、dard, either by publication of an identical text or by endorsement, at the latest by May 2013, and conflicting national standards shall be withdrawn at the latest by May 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN an

21、d/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Cze

22、ch Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdo

23、m. DIN EN 16242:2013-03 EN 16242:2012 (E) 4 Introduction Humidity plays a key role in the conservation of cultural heritage because most materials and/or deterioration mechanisms are directly or indirectly affected by humidity levels or changes. This European Standard is a guide intended to assist i

24、n providing an acceptable environment for cultural heritage objects. Humidity in air, expressed in a number of ways, is an important aspect of that environment. Therefore, the control of levels and variability of humidity reduces the risk of deterioration and is an important preventive measure, mini

25、mising the need for future conservation interventions. This European Standard is a guide to specifying adequate procedures for measuring humidity in air and the minimum characteristics of instruments for such measurements so that they are carried out to an appropriate level of accuracy. Although sta

26、ndards exist for measuring humidity in air in other fields like meteorology or ergonomics of thermal environments, this standard focuses on the specific requirements of cultural objects. This document is one of the series of European Standards intended for use in the study of environments for cultur

27、al property. DIN EN 16242:2013-03 EN 16242:2012 (E) 5 1 Scope This European Standard gives guidance and specifies procedures and instruments for the measurement of relative humidity (RH) in air, in outdoor or indoor environments. It indicates how RH can be directly measured or how it can be calculat

28、ed from air temperature, wet-bulb temperature and dew-point temperature. This standard contains recommendations for accurate measurements of ambient conditions and moisture exchanges between air and cultural heritage objects. It is addressed to anyone in charge of environmental diagnosis, conservati

29、on or maintenance of buildings, collections or single objects. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the

30、 latest edition of the referenced document (including any amendments) applies. EN 15757:2010, Conservation of Cultural Property - Specifications for temperature and relative humidity to limit climate-induced mechanical damage in organic hygroscopic materials EN 15758:2010, Conservation of Cultural P

31、roperty - Procedures and instruments for measuring temperatures of the air and of the surfaces of objects EN 60751, Industrial platinum resistance thermometers and platinum temperature sensors (IEC 60751) EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratori

32、es (ISO/IEC 17025) ISO/IEC Guide 98-3 Uncertainty of measurement - Part 3: Guide to the expression of uncertainty in measurement (GUM) 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 15758:2010 and the following apply. 3.1 absolute humidity (AH) volum

33、e density of water vapour, i.e. the mass of vapour contained in the unit volume of moist air AH =mvV, expressed in g/m3Note 1 to entry: This volume density is also noted v (v for volume) 3.2 atmospheric (or barometric) pressure (p) pressure is the force per unit area exerted by the air column above

34、the measuring point, expressed in hPa (hectopascal) Note 1 to entry: 1 hPa = 1 mbar (millibar) 3.3 barometer instrument for measuring atmospheric pressure DIN EN 16242:2013-03 EN 16242:2012 (E) 6 3.4 dew-point hygrometer instrument for measuring the temperature at which a cooled parcel of air become

35、s saturated with water vapour 3.5 dew-point temperature (DP) temperature to which air is cooled at constant pressure and constant water vapour content in order for saturation to occur Note 1 to entry: This is expressed in degrees Celsius (C). EN 15758: 2010 3.6 dry air atmospheric air without water

36、vapour 3.7 dry-bulb temperature (T, t) actual air temperature. In a psychrometer, the temperature reached by the thermometer having the dry bulb Note 1 to entry: Capital T is used when the measurement is expressed in Kelvin (K); lowercase t when expressed in degrees Celsius (C). 3.8 equilibrium mois

37、ture content (EMC) moisture content at which a material neither loses nor gains moisture from the surrounding atmosphere at given relative humidity and temperature levels. Expressed in g/kg as the ratio of the mass of water mwcontained in the material and the dry mass mdmof the same material, i.e.:

38、EMC = dmwmm3.9 frost-point temperature temperature to which moist air must be cooled, at constant pressure and humidity mixing ratio, in order that it shall be saturated with respect to ice, expressed in degrees Celsius (C) 3.10 hygrograph instrument for measuring relative humidity (see hygrometer)

39、and recording over time Note 1 to entry: Generally, a mechanically or electrically driven drum supporting a strip chart with RH graduation where an ink pen traces a time plot of the ambient humidity. 3.11 hygrometer instrument measuring relative humidity Note 1 to entry: It generally comprises a sen

40、sor, which is set in equilibrium with the air, and a system that transforms the signal from the sensor into humidity readings. 3.12 mixing ratio or humidity mixing ratio (MR) ratio of the mass of water vapour mvto the mass of dry air ma, i.e. avmmMR = , expressed in g/kg3.13 moist air mixture of dry

41、 air and water vapour DIN EN 16242:2013-03 EN 16242:2012 (E) 7 3.14 psychrometer instrument for measuring the dry- and wet-bulb temperatures to calculate relative humidity and other related variables Note 1 to entry: It consists of two identical thermometers, one of which is sheathed in wet wicking,

42、 and a fan to ensure their ventilation at a constant velocity in order to reach equilibrium with air. Thermometer readings are expressed in degrees Celsius (C). Some electronic instruments provide readings of relative humidity (%), dew point (C) and other related variables. 3.15 relative humidity (R

43、H) ratio of the actual vapour pressure of the air to the saturation vapour pressure SOURCE: EN 15757:2010 3.16 measuring range interval of values that are intended to be measured, or that are potentially measurable, or that have been measured, specified by their upper and lower limits 3.17 repeatabi

44、lity ability of the measuring instrument to reproduce the same output when successively measuring the same value of the air or the surface under investigation, taken under the same conditions Note 1 to entry: This is expressed as percent of the range. SOURCE: EN 15758:2010 3.18 resolution smallest d

45、ifference between indications of a displaying device that can be meaningfully distinguished 3.19 response time time interval between the instant when the parameter under investigation is subjected to a specified abrupt change and the instant when the response reaches and remains within specified lim

46、its around its final steady value Note 1 to entry: The response time is typically expressed as the time needed to reach 63,2 % of the final value and in this case is called time constant, or 90 % or 95 % of it. The 90 % response time is 2,3 times longer than the time constant and the 95 % response t

47、ime is three times longer. The response time is independent of the span of the output change. SOURCE: EN 15758:2010 3.20 saturation vapour pressure (esat(t) maximum pressure of the water vapour in equilibrium with plane surface of pure water, expressed in hPa (hectopascal) 3.21 sensor device that se

48、nses either an absolute value or a change in a physical quantity and converts them into a useful signal for an information-gathering system DIN EN 16242:2013-03 EN 16242:2012 (E) 8 3.22 thermometer instrument to measure temperature which comprises a sensor which is placed in thermal equilibrium with the air (if it measures the air temperature) or the surface, sometimes a probe that contains and protects the sensor, and a system that transforms the input from the sensor into an output expressed in degrees Celsius