© ISO 2016 Plastics — Method of controlled acceleration of laboratory weathering by increased irradiance Plastiques — Méthode d’accélération contrôlée du vieillissement en laboratoire par irradiance a[.]
TECHNICAL SPECIFICATION ISO/TS 19022 First edition 2016-02-01 Plastics — Method of controlled acceleration of laboratory weathering by increased irradiance Plastiques — Méthode d’accélération contrôlée du vieillissement en laboratoire par irradiance accrue Reference number ISO/TS 19022:2016(E) © ISO 2016 ISO/TS 19022:2016(E) COPYRIGHT PROTECTED DOCUMENT © ISO 2016, Published in Switzerland All rights reserved Unless otherwise specified, no part o f this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission Permission can be requested from either ISO at the address below or ISO’s member body in the country o f the requester ISO copyright o ffice Ch de Blandonnet • CP 401 CH-1214 Vernier, Geneva, Switzerland Tel +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org ii © ISO 2016 – All rights reserved ISO/TS 19022:2016(E) Contents Page Foreword iv Introduction v Scope Normative references Terms and definitions Symbols and abbreviated terms Principle Apparatus 6.1 6.2 General 6.6 Test chamber 6.3.1 6.3.2 Spectral irradiance f Radiometer Black-standard/black-panel thermometer 6.3 Lab o rato ry radiatio n s o urce 6.7 Wetting and humidity- co ntro l equip ment 6.7.1 General 6.7.2 Relative- humidity co ntro l equip ment 6.7.3 S p ray sys tem General 6.3 6.4 6.5 I rradiance uni o rmity Tes t chamb er temp erature and relative humidity 4 6.8 Specimen holders 6.9 Apparatus to assess changes in properties Test specimens Test method Exposure conditions 9.1 Radiation 9.2 Temperature 9.2.1 Black-standard and black-panel temperature 9.2.2 Chamber air temperature 9.2.3 Specimen surface temperature f f 10 Procedure 10.1 10.2 Mounting the test specimens 10.3 Exposure Measurement of radiant exposure 10.5 Determination of changes in properties after exposure 11 Test report Annex A (informative) Principle of reciprocity Bibliography 10 9.3 H umidity o Relative humidity o 9.3 S p ray cycle General chamb er air 9.3 chamb er air 7 7 0.4 © ISO 2016 – All rights reserved iii ISO/TS 19022:2016(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies) The work o f 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-governmental, in liaison with ISO, also take part in the work ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters o f electrotechnical standardization The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part In particular the different approval criteria needed for the di fferent types o f ISO documents should be noted This document was dra fted in accordance with the editorial rules of the ISO/IEC Directives, Part (see www.iso.org/directives) Attention is drawn to the possibility that some o f the elements o f this document may be the subject o f patent rights ISO shall not be held responsible for identi fying any or all such patent rights Details o f any patent rights identified during the development o f the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents) Any trade name used in this document is in formation given for the convenience o f users and does not constitute an endorsement For an explanation on the meaning o f ISO specific terms and expressions related to formity assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary in formation The committee responsible for this document is ISO/TC 61, Plastics, Subcommittee SC 6, Ageing, chemical and environmental resistance iv © ISO 2016 – All rights reserved ISO/TS 1902 :2 016(E) Introduction A realization o f the acceleration o f laboratory weathering under controlled conditions is an essential requirement for delivering reliable and fast prediction o f material durability In this connection, the correlation to real use aging behaviour is being checked constantly The fundamental parameters of a weathering test are simulated solar radiation, heat and moisture The induced change in the material properties, among other things, is determined by the irradiance level and relative spectral irradiance of simulated solar radiation incident on the material surface during the test, the surface temperature, and the level of moisture An increase in some well-known weather parameters, continuously monitored outdoors, o ffers opportunities to speed up the weathering process outdoors and in the laboratory Since 1967, acceleration o f outdoor weathering with instruments for intensified weathering using concentrated solar radiation (according to ISO 877-3) became a common practice By concentrating the natural solar radiation with Fresnel mirrors, irradiances o f five to six times higher than the maximum natural level has been reached Already in 1996, a screening procedure with very high irradiances for dyed textiles were developed which enabled the reduction o f the test duration for lightfastness grades from five days to seven days to two and a hal f days [5] However, the applicability o f an increased irradiance for deterministic acceleration o f weathering without a specific knowledge o f material properties requires that the degradation o f material (at constant temperature and moisture conditions) has to be dependent on the applied radiant exposure only, irrespective o f the irradiance level and resulting exposure duration used during the test For some materials fulfilling this criterion, the acceleration o f weathering has been demonstrated success fully [6][7 ][8][9] This criterion is not always fulfilled since an increase in the irradiance might not always produce the expected increase in the weathering acceleration due to possible and a priory unknown to the operator nonlinear dependence of the photochemical processes on the irradiance level Moreover, the overall material degradation might be strongly a ffected by the other weather parameters which can be modified due to the increased irradiance There are limitations in using increased irradiances There fore, the applicability and the limits o f this weathering acceleration approach are determined by the properties o f the specific material and have to be investigated systematically in each particular case In this respect, it is o f essential importance to validate an appropriate test procedure under controlled conditions in laboratory with an artificial radiation source which can provide high irradiances above the natural level with the relative spectral irradiance closely mimicking the natural solar radiation Simultaneously, the temperature o f the sample specimen surface and of the chamber air is kept constant in a wide range of irradiance level In addition, the usual wetting and rain option have to be available © ISO 2016 – All rights reserved v TECHNICAL SPECIFICATION ISO/TS 19022:2016(E) Plastics — Method of controlled acceleration of laboratory weathering by increased irradiance Scope T h i s Te ch n ic a l Sp e c i fic ation s p e c i fie s a te s t me tho d wh ich a l lows pre d ic ti ng the agi ng rate o f materi a l specimens, e.g plastics, under interest independent of the aging mechanisms as a function of radiant f extended above the normal maximum level on earth surface while keeping all relevant temperature exp o s u re T he U V i rrad i ance o a s i mu late d s olar rad iation (with a lab orator y rad i ation s ou rce) wi l l b e p a rame ters fi xe d NOTE For translucent plastics, the surface temperatures are below the white standard temperature In addition, the maximum temperature is not on the irradiated surface, it is somewhere inside the plastic material Normative references T he fol lowi ng i nd i s p en s able c u ments , i n whole or i n p ar t, a re normatively re ference d i n th i s c u ment and are for its appl ic ation For date d re ference s , on ly the e d ition cite d appl ie s For u ndate d re ference s , the late s t e d ition o f the re ference d c u ment (i nclud i ng any amend ments) appl ie s ISO 45 , Plastics — Determination of changes in colour and variations in properties after exposure to daylight under glass, natural weathering or artificial light ISO ISO -1 , Plastics — Methods of exposure to laboratory light sources — Part 1: General guidance 70 , Plastics — Instrumental determination of radiant exposure in weathering tests — General guidance and basic test method ISO , Plastics — Methodology for assessing polymer photo ageing by FT-IR and UV-visible spectrometry ISO/TR Plastics — Standard table for reference global solar spectral irradiance at sea level — 10 178 01 , Horizontal, relative air mass CIE Publication No 85:1989, Solar spectral irradiance Terms and definitions For the pu r p o s e s o f th i s c u ment, the fol lowi ng term s and defi n ition s apply 3.1 radiant exposure H rad i ant energ y p er un it N o te to entr y: Rad i a nt e xp o s u re i s given b y the fol lowi n g for mu l a: H = ∫ E × dt where E t is the irradiance, in watts per square metre (W × m ); is the exposure time, in seconds (s) N o te to entr y: −2 H i s there fo re e xp re s s e d i n j ou le s p er s qu a re me tre ( J × m-2 ) © ISO 2016 – All rights reserved ISO/TS 19022:2016(E) 3.2 solar radiation global solar radiation solar radiant flux, both direct and di ffuse, received on a horizontal plane unit area from a solid angle o f 2π steradians [SOURCE: ISO/TR 17801, 3.1, modified — irradiance has been replaced by radiation] Note to entry: In this Technical Specification, “solar radiation” always means “global solar radiation” Symbols and abbreviated terms CHT BST BPT WST WPT chamber air temperature (ambient air temperature) black-standard thermometer (insulated surface temperature sensor) black-panel thermometer (uninsulated surface temperature sensor) white standard thermometer (insulated surface temperature sensor) white panel thermometer (uninsulated surface temperature sensor) Principle A xenon or fluorescent UV radiation source (other radiation sources are possible), fitted with filters (i f necessary), is used to simulate pre ferably the relative spectral irradiance o f solar radiation according to CIE Publication No 85:1989, Table or solar radiation filtered by window glass A standard test method (e.g ISO 4892-2, ISO 4892-3) or a di ffering/non-standardized weathering test method shall be conducted as a basis for further investigations The base level test shall use weathering parameters (irradiance, temperatures, relative humidity) which are not above a maximum natural level (e.g irradiance in the wavelength range 300 nm to 400 nm smaller than 66 W/m ) As a second step, the irradiance is increased step by step above the natural level While the irradiance is increased above the maximum level (at least three levels) or decreased, all other test parameters (relative spectral irradiance, chamber air temperature, relative humidity) shall be kept constant (unchanged) I f used, the influence o f a spray/dry cycle shall be care fully considered The test results (e.g colour change, carbonyl formation) shall be plotted as a function o f the radiant exposure Apparatus 6.1 General The equipment comprises a climate chamber with a chamber air temperature and relative humidity measurement device In the climate chamber, included is a radiation source The radiation source may generate UV, visible radiation, and in frared radiation similar to solar radiation with appropriate filter systems A cooling system for the laboratory simulated solar radiation source and a fixture for the specimens are included in the chamber as well 6.2 Test chamber The design o f the test chamber may vary, but it shall be constructed from inert material In case o f radiation sources including VIS and IR, it shall be equipped with a blower which generates a defined airflow to be directed across the specimens In addition to the controlled lamp wattage, the test chamber shall provide for control of chamber air temperature radiation shielded For exposures that © ISO 2016 – All rights reserved ISO/TS 902 : 01 6(E) require control o f humidity, the test chamber shall include humidity-control facilities that meet the requirements of ISO 4892-1 NOTE I f the lamp system (one or more lamps) is centrally positioned in the chamber, the e ffect o f any eccentricity o f the lamp(s) on the uni formity o f exposure may be reduced by using a rotating frame carrying the specimens or by repositioning or rotating the lamps Should any ozone be generated from operation o f the lamp(s), the lamp(s) shall be isolated from the test specimens and operating personnel I f the ozone is in an air stream, it shall be vented directly to the outside of the building 6.3 Laboratory radiation source 6.3 General The laboratory solar radiation sources (e.g xenon arc lamp, fluorescent UV lamp) may emit radiation from below 270 nm in the ultraviolet through the visible spectrum and into the infrared In order to simulate solar radiation with lamps which emit the full spectrum o f solar radiation (UV, VIS, and IR radiation), filters shall be used to remove short wavelength UV radiation In addition, filters to remove in frared radiation may be used to prevent unrealistic heating o f the test specimens NOTE Solar spectral irradiance for a number of different atmospheric conditions is described in CIE Publication No 85 The benchmark solar radiation used in this Technical Specification is that defined in CIE No 85:1989, Table A recalculated Table is available in ISO/TR 17801 (better wavelength resolution) NOTE I f laboratory radiation sources are used which emit serious amounts in the IR and VIS range, sur face temperatures are a ffected by sur face heating Then, actions to adjust specimen sur face temperatures have to be taken 6.3 Spectral irradiance Filters are used to filter xenon-arc or other laboratory radiation sources in order to simulate solar radiation (CIE Publication No 85:1989, Table 4) The minimum and maximum levels of the relative spectral irradiance are given in the used standard applications (e.g ISO 4892-2, ISO 4892-3) During the test, the relative spectral irradiance shall not be changed considerably An evaluation method shall be used to compare the relative spectral irradiance at different irradiance levels NOTE The deviation of the relative spectral irradiance at the lowest level from the highest level can be calculated according to ISO/TR 18486 NOTE The following wavelength ranges are recommended for the comparison of the relative spectral irradiance: 290 nm to 320 nm, 320 nm to 340 nm, 340 nm to 360 nm, and 360 nm to 400 nm NOTE Xenon arc and fluorescent UV lamps can run at variable wattages (which the lamp is specified for) without a significant change o f the relative spectral irradiance NOTE For natural and artificial sun radiation, the irradiance o f 60 W/m in the wavelength range of 300 nm to 400 nm or 0,51 W/(m × nm−1) at 340 nm indicates the one sun level This does not mean that higher irradiances can appear (66 W/m at 300 nm to 400 nm or 0,8 W/m at 340 nm acc new calculation of CIE 85, Table 4) 6.3 Irradiance uniformity The irradiance at any position in the area used for specimen exposure shall be at least 90 % o f the maximum irradiance For some materials o f high reflectivity, high sensitivity to irradiance and temperature, periodic repositioning o f specimens is recommended to ensure uni formity o f exposures, even when the irradiance uni formity in the exposure area is within the limits © ISO 2016 – All rights reserved ISO/TS 902 : 01 6(E) 6.4 Radiometer A radiometer shall be used to measure and control irradiance during the test procedure The radiometer sha l l comply with the re qui rements outl i ne d i n I S O -1 a nd I S O 70 6.5 Test chamber temperature and relative humidity The chamber temperature sensor shall located, radiation-shielded, and combined with a sensor which me a s ure the relative hu m id ity i n the e xhau s t a i r duc t For e xac t c a l ibration o f the field cha mb er temp eratu re a nd relative field s en s or, it i s ne ce s s a r y to move a calibrated working reference standard and the instrument sensor to about the same position so for that a b a lance d temp eratu re and hum id ity c an b e s e t the me a s u ri ng s en s ors and the chamb er r C a l ibration ta ke s place as s o on a s the whole s ys tem i s i n therma l b a la nce 6.6 Black-standard/black-panel thermometer T he b lack- s ta nda rd or black-p anel thermome ter u s e d s l l comply with the re qui rements devices given in ISO The preferred maximum surface temperature device is the black-standard thermometer for the s e -1 6.7 6.7.1 Wetting and humidity-control equipment General Sp e ci men s may b e e xp o s e d to moi s ture i n the form o f water s pray or conden s ation, or by i m mers ion I f condensation, immersion or other methods are used to expose the specimens to moisture, details of the procedures and exposure conditions used shall be included in the exposure report NO TE We tti n g c ycle s can h ave s ign i fic a nt i n fluence on the te s t re s u lts Re s u lts can d i ffer fo r ke ep i n g constant either the wetting duration (recommended for bulk related properties and/or thick samples) or the nu mb er o f we tti ng c ycle s (re co m mende d 6.7.2 for s u r face rel ate d p rop er tie s a nd/or th i n s a mp le s) Relative-humidity control equipment For e xp o s u re s where relative -hu m id ity control i s re qu i re d, the lo cation o f the s en s ors u s e d to me as u re the hu m id ity sh a l l b e a s s p e c i fie d i n I S O -1 6.7.3 Spray system T he te s t ch amb er may b e e qu ipp e d with a me a n s o f d i re c ti ng a n i nterm ittent water s pray onto the fronts or b acks o f the te s t s p e ci men s u nder s p e ci fie d cond ition s T he s pray sha l l b e u n i form ly d i s tribute d over the s p e ci men s T he s pray s ys tem s l l b e made from corro s ion-re s i s tant materi a l s th at no t contam i nate the water employe d T he water s praye d onto the s p e c i men s u r face s sh a l l comply with the re qu i rements i n I S O -1 6.8 Specimen holders Sp e ci men holders may b e i n the form o f an op en frame, le avi ng the b acks o f the s p e ci men s exp o s e d, or they may provide the s p e c i men s with a s ol id b acki ng T hey s l l b e made no t a ffe c t the re s u lts o f the exp o s u re, for from i ner t materi a l s that wi l l e xample, non- oxid i z i ng a l loys o f a lum i n iu m or s ta i n le s s s te el B s s , s te el or copp er sh a l l no t b e u s e d i n the vic i n ity o f the te s t s p e c i men s T he b acki ng u s e d m ight a ffe c t the re s u lts , as m ight any s p ace b e twe en the b acki ng and the te s t s p e ci men, p ar tic u la rly with transparent specimens and shall be agreed upon between the interested parties © ISO 2016 – All rights reserved ISO/TS 19022:2016(E) 6.9 Apparatus to assess changes in properties If an International Standard relating to the determination of the properties chosen for monitoring the International Standard concerned shall be used changes in properties exists (see, in particular, ISO 4582 or ISO 10640), the apparatus specified by the NOTE Di fferent material properties o f the same material may act di fferently The property choice is o f basic relevance for evaluating the weathering acceleration Test specimens Test specimens shall be according to ISO 4892-1 Test method Select a standard test method or create an own test method 8.1 8.2 a) b) c) d) The test parameters are the following: relative spectral irradiance (preferred simulated solar radiation acc ISO/TR 17801); irradiance; chamber air temperature (CHT); surface temperature of the specimen (BST or BPT); e) relative humidity; f ) rain cycle NOTE For some tests, rain cycles are not specified or not necessary Select the lowest irradiance level from the following: a) (60 ± 2) W × m−2 (300 nm to 400 nm); b) (0,51 ± 0,02) W × m−2 × nm−1 (340 nm) 8.3 NOTE The lowest irradiance level is normally defined by the selected standard test method but irradiance levels below the standard irradiance level are also allowed 8.4 Run the test at the lowest irradiance level Increase the irradiance above the natural level ≥60 W × m−2 (300 nm to 400 nm) and 0,51 W × m-2 (340 nm) The deviation from the set point (±x W × m-2 ) grows about proportional with the irradiance 8.5 8.6 Run the test at increased irradiance level while keeping all other test parameters constant [relative spectral irradiance, chamber air temperature (≤±3 °C), surface temperature or black-standard or blackpanel temperature (≤± 3°C), relative humidity (≤±10 %) and rain cycle] Several increased irradiance levels shall be used (at least four) NOTE Photo reactions may depend on the Arrhenius relation (a ∆T o f °C can cause a property change o f about %) 8.7 Plot the test results (property changes, e.g colour change or carbonyl formation, see also ISO 4582) as a function of the radiant exposure © ISO 2016 – All rights reserved ISO/TS 902 : 01 6(E) NO TE W hen the p rop er ty ch a nge i s p lo tte d a s a fu nc tio n o f rad ia nt e xp o s u re , the me a s u re d data wi l l va r y even i f the te s t d ata a re me a s u re d at the s a me rad i a nt e xp o s u re a nd the l aw o f re c ipro c ity m ayb e fu l fi l le d O n the o ther h a nd , it i s no t a lways p rac tic a l to s to p a te s t at the s a me rad i a nt e xp o s u re NOTE Other evaluations of the test are possible, e.g if the test data are available at the same radiant exposure two i r rad i a nce level s c a n b e comp a re d d i re c tl y 8.8 a fit o f the data (Pears o n co rrelatio n co e fficient can b e ap p ro p riate) For a go o d cor rel ation , the Pe a rs on co rrel ation co e ffic ient i s > ,9 NO TE fro m C alculate the deviatio ns Exposure conditions 9.1 Radiation Un le s s o ther wi s e s p e ci fie d, control the i rrad ia nce at the level s i nd ic ate d i n the s ele c te d s tandard O ther i rrad iance level s may b e u s e d when agre e d up on b y the i ntere s te d p ar tie s T he i rrad ia nce a nd the p a s s band in which it was measured shall be included in the exposure report 9.2 9.2 Temperature Black- standard and black-panel temperature I f a black- s ta nda rd or a black-p anel temp eratu re i s s p e c i fie d i n the s ele c te d s ta ndard , the s e s ur face temp erature s en s ors s l l b e u s e d to defi ne the temp eratu re level du ri ng the te s t pro ce du re O ther s u r face temp eratu re s may b e u s e d when agre e d up on b y the i ntere s te d p ar tie s , but s l l b e stated in the exposure report I f water s pray is u s e d, the temp eratu re re qu i rements apply to the end o f the dry p erio d I f the thermome ter e s no t re ach a s te ady- s tate du ri ng the d r y p erio d a fter the shor t water- s pray p a r t o f the c ycle, che ck whe ther the s p e c i fie d temp eratu re i s re ache d du ri ng a longer d r y p erio d a nd s ider us i ng th i s longer d r y p erio d NO TE D u ri n g the water- s pray p a r t o f the c ycle , the b l ack- s ta nd a rd o r b l ack-p a nel temp eratu re wi l l b e clo s e to that of the water used 9.2 Chamber air temperature E xp o s u re s c an b e r u n either with the ch amb er r temp eratu re (C H T ) control le d at a s p e c i fie d level or a l lowi ng the C H T to fi nd its own level Exposures with controlled CHT are preferred I f the C H T i s no t control le d , the s p e ci fic s u r face temp eratu re o f the s p e ci men s s l l b e me a s ure d NOTE f f f lower limit and the BST temperature as the upper limit temperature (massive plastic samples can have higher lies somewhere between the two cited limits For xenon a rc l a mp s (or s i m i l a r u l l s p e c tr u m s ol a r s i mu l ato rs: U V, VI S , I R rad i ation) , the p o s s ib le s p e c i men s u r ace temp eratu re i s l i m ite d b y the temp eratu re o the a i r s u r ro u nd i ng the s a mp le (C H T ) a s the temp eratu re s th a n the temp eratu re i nd ic ate d b y a B S T ) I t i s then a s s u me d th at the ac tu a l s p e c i men temp eratu re 9.2 Specimen surface temperature The specimen surface temperature is the decisive measure It is recommended to measure the surface temperature In addition, a WST or WPT sensor can help to evaluate the specimen temperature © ISO 2016 – All rights reserved ISO/TS 19022:2016(E) Nevertheless, the test should be controlled by BST or BPT and CHT NOTE If the test method described under Clause is used (increasing irradiance up to threefold solar smaller than the tolerance described in 8.6 irradiance with unchanged BST or BPT and CHT), the temperature change o f the specific specimen sur face is 9.3 Humidity of chamber air 9.3.1 Relative humidity of chamber air Exposures can be conducted either with the relative humidity controlled at a specified level or allowing the relative humidity to find its own level Exposures with controlled relative humidity are pre ferred NOTE 9.3.2 For some materials, the relative humidity might not be important Spray cycle The spray cycle used shall be as agreed between the interested parties, but is normally defined by the used test method NOTE Spray cycles can have significant e ffect on the exposure result and has to be care fully considered By increasing irradiance, either the wetting duration or the number o f spray cycles during a test is reduced 10 Procedure 10.1 General It is recommended that at least three test specimens of each material evaluated be exposed in each run to allow statistical evaluation of the results 10.2 Mounting the test specimens Attach the specimens to the specimen holders in the equipment in such a manner that the specimens are not subject to any applied stress Identi fy each test specimen by suitable indelible marking, avoiding areas to be used for subsequent testing As a check, a plan o f the test-specimen positions may be made If desired, in the case of specimens used to determine change in colour and appearance, a portion of each test specimen may be shielded by an opaque cover throughout the exposure This gives an unexposed area adjacent to the exposed area for comparison This is useful for checking the progress o f the exposure, but the data reported shall always be based on a comparison with file specimens stored in the dark 10.3 Exposure Before placing the specimens in the test chamber, be sure that the apparatus is operating under the desired conditions Program the apparatus with the selected conditions to operate continuously for the required number o f cycles at the selected exposure conditions Maintain these conditions throughout the exposure, keeping any interruptions to service the apparatus and to inspect the specimens to a minimum Expose the test specimens, the radiometer and the sur face temperature sensor for the specified period I f it is necessary to remove a test specimen for periodic inspection, take care not to touch the exposed sur face or alter it in any way A fter inspection, return the specimen to its holder or to its place in the test chamber with its exposed surface oriented in the same direction as before © ISO 2016 – All rights reserved ISO/TS 19022:2016(E) 10.4 Measurement of radiant exposure Mount and calibrate the radiometer so that the irradiance at the exposed surface of the test specimen is reported -2 ), in the f -2 f × nm-1) nm) E xpre s s the exp o s u re s tage s i n term s o waveleng th b a nd rad ia nt e xp o s ure s , i n j ou le s p er s quare me tre ( J × m rom 0 n m to 0 n m, or i n j ou le s p er s quare me tre p er na nome tre ( J × m at the waveleng th s ele c te d (e g 10.5 Determination of changes in properties after exposure T he s e s l l b e de term i ne d a s s p e c i fie d i n I S O 45 82 or i n I S O 10 as fa r a s p o s s ible O ther prop er tie s may b e u s e d i f agre e d up on by a l l i ntere s te d p ar tie s D i fferent materia l prop er tie s o f the s a me materi a l may ac t d i fferently T he prop er ty choice i s o f b as ic relevance for evaluating the weathering acceleration 11 Test report Test report shall be according to ISO 8 -1 © ISO 2016 – All rights reserved ISO/TS 19022:2016(E) Annex A (informative) Principle of reciprocity T he genera l i z ation o f the i n fluence o f the i rrad i ance level on the acceleration o f materia l de gradation i s provide d b y the s o - c a l le d pri nciple o f re c ipro c ity prop er ty ch ange s are cla s s i fie d i nto the fol lowi ng [10] In the framework of this principle, all material two cla s s e s: a) materials whose induced degradation during the weathering test is independent on the irradiance level at fi xe d appl ie d rad i ant e xp o s u re when a l l o ther we atheri ng p ara me ters are kep t s ta nt; b) all other materials M ateria l prop er ty change s b elongi ng to the fi rs t cla s s are s a id to fu l fi l l the pri nc iple o f re cipro city H ere, the de gradation o f materi a l i s governe d by the level o f the rad i ant e xp o s u re on ly and i n th i s c a s e, the acceleration o f we atheri ng i s l i m ite d b y the ma xi ma l i rrad ia nce level wh ich c an b e re ache d wh i le ke epi ng a l l o ther relevant p arame ters fi xe d T here fore, the exp o s u re du ration ca n b e s i mply shor tene d b y the en hancement fac tor o f the i rrad ia nce level T he s ituation i s d i fferent for the s e cond cla s s o f materi a l s I n th i s c as e, the rate o f i nduce d degradation o f s ome materia l prop er ty u nder i ntere s t be obtained through the Formula (A.1): [10] ΔP = Ep ΔP can (A.1) where ΔP i s the ch ange o f s ome materia l prop er ty; E is the irradiance level; p i s the s o c a l le d S chwarz s ch i ld co e fficient NOTE p m ay va r y b e twe en , a nd , Knowledge of p provides a precise estimation of the aging behaviour at elevated level of irradiance Therefore, the procedure to validate this parameter is an essential condition for realization of deterministic weathering acceleration © ISO 2016 – All rights reserved ISO/TS 902 : 01 6(E) Bibliography [1] [2] [3] [4] [5] [6] ISO 877-3, Plastics — Methods ofexposure to solar radiation — Part 3: Intensified weathering using concentrated solar radiation ISO 4892-2, Plastics — Methods of exposure to laboratory light sources — Part 2: Xenon-arc lamps ISO 4892-3, Plastics — Methods of exposure to laboratory light sources — Part 3: Fluorescent UV lamps ISO/TR 18486, Plastics —Calculation of the goodness of fit of the spectral distribution of a solar simulator to a reference solar spectral distribution Ri e ker J , & Wob s er K Untersuchung über die Anwendbarkeit der Kurzzeitbelichtung für die betriebliche Kontrolle der Lichtechtheitseigenschaften farbiger Textilien “, Melliand Textilberichte 9, 1996 C hin J., Ngu yen T., B yrd E., M artin J The Law of Reciprocity Applied to High Radiant Flux Weathering Studies ”, 2nd European Weathering Symposium, 2005, Natural and Artificial Ageing o f polymers, CEEES Publication No 6, 2005, ISBN 3-9808382-9-3, p 105 - 114 [7] [8] [9] H ardc astle H.K A Characterization of the Relationship Between Light Intensity and Degradation Rate for Weathering Durability”, 2nd European Weathering Symposium, 2005, Natural and Artificial Ageing o f polymers, CEEES Publication No 6, 2005, ISBN 3-9808382-9-3, p 115 - 130 S tuck J.-W Erfahrungen und neue Möglichkeiten bei der Schnellbelichtung“, DEK Fachtagung „Echtheitsprüfungen in der Textilindustrie “, Gelnhausen, Oktober 1996 9/9 B oxh ammer J Kürzere Prü fzeiten bei thermischer und strahlungsbedingter Alterung von polymeren Werksto ffen durch verschär fte Prüfbedingungen“, Tagungsband der 29 Jahrestagung der GUS, 2000, pp 8.1–8.15 [10] T rubiroh a P., Geburtig A., Wach tendor f V The Principle of Reciprocity and its Limits“, 3rd European Weathering Symposium, 2007, Natural and Artificial Ageing o f polymers, CEEES Publication No 8, 2007, ISBN 978-3-9810472-3-3, p 243 – 258 10 © ISO 2016 – All rights reserved ISO/TS 902 : 01 6(E) ICS 83.080.01 Price based on 10 pages © ISO 2016 – All rights reserved