GUIDANCE ON PRODUCT EMISSIONS BY LABORATORY TESTING THE EPHECT EXPERIENCE

GUIDANCE ON PRODUCT EMISSIONS BY LABORATORY TESTING THE EPHECT EXPERIENCE John Bartzs, Evangelos Tols, George Efthmou (UOWM) Peder Wolkoff (NRCWE) Maranne Stranger, Frederck Maes, Eddy Goelen (VITO) Gabrela Ventura, Eduardo de Olvera Fernandes (IDMEC) September 2013

DISTRIBUTION LIST Vlaamse Instellng voor Technologsch Onderzoek, Mol, Belgum Unversty of Western Macedona Research Commttee, Kozan, Greece Agence Natonale de Sécurté Santare, Almentaton, Envronnement, Traval, Pars, France Technsche Unverstät München, Germany Natonal Research Centre for the Workng Envronment, Copenhagen, Denmark Insttuto de Engenhara Mecanca Envronment, Porto, Portugal Unversta Degl Stud d Mlano, Italy Ipsos Belgum, Waterloo, Belgum UOWM, VITO, NRCWE, IDMEC All rghts on the materals descrbed n ths document rest wth UOWM, VITO, NRCWE, and IDMEC. Ths document s produced n the frame of the EPHECT project. The EPHECT-project s co-funded by the European Unon n the framework of the health Programmes 2006-2013. The nformaton and vews set out n ths document are those of the author(s) and do not necessarly reflect the offcal opnon of the European Unon. Nether the European Unon nsttutons and bodes nor any person actng on ther behalf, nor the authors may be held responsble for the use whch may be made of the nformaton contaned heren. Reproducton s authorzed provded the source s acknowledged. II

TABLE OF CONTENTS Dstrbuton Lst II Table of contents III Lst of fgures IV Lst of tables V Nomenclature VI Chapter 1: Introducton 8 Chapter 2: Consumer product testng 9 2.1 Background 9 2.2 Pollutant Mass transfer mechansms 10 2.3 Parameters that nfluence the mass transfer 12 2.4 Selecton of test chamber 13 2.4.1. Addtonal consderatons 14 2.5 The preparaton phase for testng 15 2.5.1 Start-up condtons 15 2.5.2 Intal test condtons 16 2.5.3 Product specfc test chamber condtons 16 Lqud consumer and personal care products 17 Sold consumer and personal care products 20 2.6 Testng and Samplng phase 21 2.7 Test Duraton 22 Chapter 3: EPHECT analytcal methods 26 Chapter 4: Emsson estmatons 28 4.1. Basc Theory 28 4.2. Emsson Estmatons 33 Chapter 5: Concludng remarks and future consderatons 36 Reference lst 38 III

LIST OF FIGURES Fgure 2.1 Dagram of the knetc processes nvolved n the mass transfer model of VOCs from materal surfaces. Fgure 2.2 The test chamber concentraton measurements pattern. Fgure 2.3 The deal concentraton tme profle for a constant emttng source. Fgure 2.4 Test chamber measured lmonene concentraton dstrbuton from a ktchen cleanng agent. Fgure 4.1 The measured concentraton smplfed pattern. Fgure 4.2 The proposed new measurement concentraton pattern n a chamber test. Fgure 5.1 The measured concentraton smplfed pattern. IV

LIST OF TABLES Table 1.1 Selecton of EPHECT consumer products 1 Table 2.1 Start-up condtons of consumer product emsson testng 9 Table 2.2 Intal condtons for EPHECT consumer product emsson testng 9 Table 2.3 The deal room dmensons and loadng factors accordng to CEN TC 351 WG2 17 Table 2.4 Expermental condtons to test lquds, packed n a flask 18 Table 2.5 Expermental condtons to test lquds, packed n a spray bottle 19 Table 2.6 Expermental condtons to test lquds, packed to be volatlzed Error! Bookmark not defned. Table 2.7 Expermental condtons to test sold products; candle emssons 20 Table 3.1 Overvew of the analytcal methods 20 Table 4.1 Overvew of the EPHECT analytcal methods 26 V

NOMENCLATURE Symbol Descrpton Unts A [mass unts h -1 ] Rate of adsorpton on surfaces n the chamber C Concentraton n the chamber [mass unts m -3 ] [mass unts m -3 ] C ext Concentraton of the nlet ar CM Measured concentraton wthn the samplng [mass unts m -3 ] tme C max Peak concentraton [mass unts m -3 ] CT Average concentraton over Δt [mass unts m -3 ] C 0 Intal pollutant concentraton [mass unts m -3 ] D [mass unts h -1 ] DT Rate of desorpton from surfaces n the chamber [hrs] Tme nterval whch ncludes both the preparaton and the samplng tme DTIN Preparaton tme [hrs] DTS Samplng tme [hrs] ER Emsson rate [mass unts h -1 ] ER 0 Peak emsson rate [mass unts h -1 ] ET Total emsson [mass unts] F [mass unts h -1 ] Removal rate by an ar cleanng devce n the chamber k Decay rate constant [h -1 ] N Number of measurements - [m 3 h -1 ] Q n Q out Ar flow rate gong n the chamber [m 3 h -1 ] Ar flow rate gong out of the chamber SER Specfc emsson rate [mass unts h -1 gr -1 ] t Tme [h] TIMTEST Total testng tme duraton [h] VI

t max [h] V Tme of maxmum observed concentraton [m -3 ] X Volume of the test chamber [mass unts h m -3 ] Rate of generaton/destructon through chemcal reactons n the chamber Δλ N Emsson strength factor [h -1 ] Δt [h] λ Tme nterval between two successve measured concentratons of the smplfed pattern [h -1 ] Ar exchange rate of the test chamber λ d Decay constant [h -1 ] VII

CHAPTER 1: INTRODUCTION Ths document addresses the strategy to measure and model product emssons, related to the household use of consumer products. Ths s based on the EPHECT project experence and the avalable expertse. The strategy more specfcally apples to the followng 15 product classes, selected for testng n the EPHECT project. Table 1.1: Selecton of EPHECT consumer products 1 all purpose cleaner 2 ktchen cleanng agent 3 floor cleanng agent 4 glass and wndow cleaner 5 bathroom cleanng agent 6 furnture polsh 7 floor polsh 8 combustble ar fresheners 9 ar fresheners (spray) 10 ar freshener, passve unts 11 ar freshener, plug-n unts 12 coatng products 13 har stylng products 14 deodorants (sprays) 15 Perfumes One of the purposes of the EPHECT Project s to explore and develop methods to measure the emsson of ar pollutants from the above mentoned products by placng them nto a clmate test chamber. The purpose of the present gudance s to present the EPHECT experence (Stranger et al. EPHECT WP6 report part I and II) together wth fndngs from the open lterature and to analyze advantages, dsadvantages, and caveats by applyng test chamber technology for chemcal emsson testng and assocated modelng strateges to estmate emsson rates of specfc compounds n a predefned model room. 8

CHAPTER 2: CONSUMER PRODUCT TESTING 2.1 Background In the recent decades, research actvtes on product emssons were manly focused on buldng materal emssons. The resultng emsson test procedures, evaluaton protocols (e.g. AgBB, Afsset 2009, GEV testng method, etc ) and standards on emsson test chamber procedures and samplng technques (ISO 16000-3, ISO 16000-6, ISO 16000-9) are well-establshed. ASTM D6670-01 (2007) descrbes a more generc strategy for volatle organc compounds (VOC) emsson testng from materals, products and equpment (buldng materals, furnture, consumer products, prnters, ar cleaners etc.) typcally used n offce and resdental buldngs, n full-scale chambers for VOC emsson testng. However, specfcally for the consumer and personal care products studed n EPHECT, dedcated standards for emsson tests are currently not avalable. Test protocols as well as the results, reported n the open lterature, vary between laboratores and are dffcult to compare, manly due to varable test condtons (ASTM D5116-10, Salthammer, 2009). Therefore, EPHECT ams at a maxmal overlap between the proposed consumer and personal care product test protocols and exstng ISO standards and other relevant emsson test/evaluaton protocols and standards for buldng materals. In buldng materal emsson testng, the products are typcally nstalled as a statc object n the test chamber, wth respect to relevant ISO standard (ISO 16000-9), test chamber dmensons, and reported loadng factors; the product emssons are assessed respectng vald emsson test protocols. The selected consumer and personal care products (Table 1.1) consst of products characterzed by exposures related to the household user patterns and user scenaros. Certan aspects of the emsson test protocols proposed n EPHECT may therefore dffer from the well-establshed buldng materal test protocols, because the emssons wll only occur when a certan nteracton between the product and the user takes place: a certan use scenaro should thus be smulated n the test chamber. An mportant aspect of an emsson test protocol s ts repeatablty for nternal use and external applcablty (reproducblty) n emsson test chambers of varous dmensons. For buldng materal emsson testng, the reproducblty wll manly be functon of the product dmensons wth respect to the loadng factor and the test condtons (respectng chamber start-up condtons and testng condtons), n addton to the overall samplng and analytcal performance of the ndvdual laboratory. For consumer product testng, the use scenaro tself can addtonally have a consderable mpact on the emsson test results. The lst of EPHECT consumer and personal care products mples a varety of use scenaros. These use scenaros are typcally a functon of the product package (sprays, flasks, etc.) and of the purpose of the product (floor cleanng agent to be dluted, floor polsh to be used undluted, etc.). The product package on the other hand s closely related to the aggregaton state of the product (sold, lqud or gaseous). Each package and product purpose thus mples a specfc user scenaro that should be smulated n the test chamber protocol, n a reproducble way, n order to assess the emsson characterstcs and factors of the consumer product. When assessng buldng product emssons n emsson test chambers, the emsson test result s typcally obtaned as specfc emsson rate per hour and per m² surface (or per kg or per m³ product 9

or per unt). It s then used to model ts concentraton n a reference room. For consumer and personal care product testng, the unts of the emsson factors are typcally related to the amount of used products. Another mportant aspect s the emsson pattern. Two products can be consdered as contnuous emttng sources of VOCs: passve and plug-n (electrc) ar fresheners, the remanng are to be consdered sources wth temporary (short-term) emsson patterns. Some of the products form a surface (coatng) flm durng the curng process that alters the mechansm of evaporaton of solvents, as dscussed below. Other products form ntally an aerosol of solvents and addtves. 2.2 Pollutant Mass transfer mechansms The mportant questons about emsson testng of buldng and consumer products are; a) what specfc pollutants are emtted that may nfluence the ndoor ar qualty and adversely affect occupants; b) how the emsson profles change over tme; and c) are the emsson test results meanngful.e. are the results ndependent of test condtons; d) can the results be translated to personal exposure for a rsk assessment. In general, the emsson can be characterzed by two fundamental physcal processes (see Fgure 2.1), partly taken from Wolkoff et al. (2005). a) Gas-phase mass transfer (.e. external dffuson) b) Source-phase mass transfer (.e. nternal dffuson) ar C boundary layer source m m s k g k s C s gas-phase mass transfer (external dffuson) surface source-phase mass transfer (nternal dffuson) Fgure 2.1 Dagram of the knetc processes nvolved n the mass transfer model of VOCs from materal surfaces. The gas-phase mass transfer model (a) s based on molecular dffuson across a lamnar boundary layer as descrbed n equaton (1), external dffuson. D SER (CS C ) kg (CS C ) (1) 10

SER s the specfc emsson rate, D s the dffuson coeffcent, s the thckness of the boundary layer, C S s the concentraton of the target VOC at the source surface and C s the concentraton of the target VOC n the ar and k g s the gas-phase mass transfer coeffcent. Process (b) s lmted by nternal dffuson from the nteror of the source to the surface and can be descrbed by equaton (2). SER k (m m ) (2) s S Here, m s s the mass of the target VOC n the source, m s the mass of the target VOC at the surface and k s s the source-phase mass transfer coeffcent. Comparng emsson test results from dfferent chambers, three dfferent scenaros have to be consdered. For k g >> k s : the emsson s controlled by the external dffuson process and the thckness of the boundary layer s drectly related to the ar velocty above the surface and turbulence, f t s a pont source or actvty related emsson (e.g. spray). Ths apples to most wet-appled or lqud buldng products and certan consumer products durng the dryng/curng phase. Thus, the external dffuson s sgnfcantly affected by both surface ar velocty/turbulence and the sample loadng factor (m 2 /m 3 ) (and assocated vapour concentraton wthn the chamber). The exact tmng of the emssons testng s also crtcal for wet samples, n partcular for temporary pont sources. Durng ths phase t s therefore paramount to control both ar velocty (and/or turbulence), n order to prevent them from nfluencng/changng the test result. However, for temporary (actvty related) pont sources lke spray products, the ar velocty/turbulence becomes dffcult to defne and measure (whch drecton), and no harmonzed practce exsts. Thus, any comparson of such temporary sources wll by nature be dffcult to compare between laboratores wth qute dfferent chamber dmensons wthout applyng rgorous control of all parameters pror to and durng testng. However, the extreme senstvty of the results to such a multtude of varables, does call nto the queston the relablty of testng wet samples and pont sources durng the curng/dryng stage or use. Further, a vapour pressure effect for such wet-lke products cannot be ruled out; thus, some agreed upon test condton s helpful, but not a guarantee for obtanng comparable emsson data. Furthermore, t s relevant to envsage that the ar velocty becomes less mportant the larger the chamber dmenson; for nstance, n a full scale chamber (20 m 3 ) and an ar change 0.5/h, the calculated ar velocty s 0.05 cm/s. For k g << k s : the emsson s controlled by the nternal dffuson process and the nfluence of the ar flow condton n the chamber should be neglgble. Ths apples to most sold buldng materals and to wet and lqud products after a surface flm have been formed. There wll be a transton phase where k g and k s compete together; thus, a more dffcult stuaton arses for k g k s or f the rato k s /k g changes over tme. For an ageng product, k s /k g wll normally reach nfnty over tme. Thus, VOC emssons controlled by nternal dffuson (dry products/materals) are largely ndependent of surface ar velocty and loadng, provded the exchange rate s fast enough to prevent a vapour pressure effect. Thus, for consumer product testng, that s characterzed by short-term or temporary actvty, related emsson profles are generally domnated by external dffuson, but for e.g. creamy products formng a coatng an addtonal nternal dffuson may occur. Thus, comparson of emsson data obtaned 11

from dfferent chambers (and even only slghtly dfferent test condtons) s by nature encumbered, even f harmonzed test condtons are attempted. Two often quoted questons about the outcome of emsson testng of buldng materals n a gven chamber are: does the chamber provde correct SERs and how comparable are the round-robn testng results wth other chambers. These questons lead to the mplct assumpton that SER data obtaned from that partcular chamber may be less relable. These questons are deceptve, especally n vew of round-robn testng, because a successful test requres that the results are ndependent of test condtons,.e. the emsson data are comparable. Ths s only the case for emssons where the mass transfer rate wthn the materal s slower than n the boundary layer (.e. nternal versus external dffuson control). However, many other factors nfluence the SER, of whch the most mportant ones are materal homogenety and laboratory performance (Oppl, 2008; Wolkoff et al., 2005). For consumer products wth temporary short-term emsson profles the ssue becomes even more dffcult, because of the dffculty of defnng and controllng exactly dentcal test and actvty condtons. An addtonal problem s loss of VOCs, f the applcaton cannot be carred out wthn the chamber tself. In theory, under well controlled envronmental condtons and satsfactory recovery (mnmal snk (wall) effect) and adequate samplng (accordng to the objectve) and analytcal performance, comparable SERs should be obtanable for nternal dffuson controlled emssons from homogeneous materals, ndependent of type of chamber. Thus, a thrd frequently asked queston s whether there exsts an deal chamber provdng SER data that would be dentcal n real scenaros,.e. a golden chamber standard. One may ask how meanngful s t to predct (model) externally controlled SERs of VOCs and SVOCs from buldng materals and consumer products n real lfe ndoor scenaros, n vew of the nherent dffcultes assocated wth the use of test chambers. These nclude all the factors that nfluence the SERs and external factors. Thus, measured SER n a test chamber, even wth adequate recovery and low wall snk effects, may not be representatve of the actual SER from the exact same buldng materal/product n a real ndoor settng. Well-knowng that chambers versus chambers may dffer, n some cases for reasons outsde of the performance of chamber tself, one should consder the objectve of the emsson test tself. Thus, the samplng strategy should reflect the objectve of the testng. Ths n EPHECT means that the emsson data should accommodate requrements set by the rsk assessment objectve,.e. the assocated health endponts of nterest. The mportant ssue here s that the rsk assessment focuses on acute effects, sem-acute effects (objectve sensory rrtaton) or longer-term (respratory) effects. Thus, the samplng strategy should be adopted accordngly, where applcable. Wth ths n mnd, one may contemplate the feasblty and meanngfulness of transformng emsson data, at least of short-term temporary (pont source) emssons to a gven model room and assume ths reflects the personal exposure. Other emsson decay models are avalable smply by use of the known amount of emttng compounds n the product. 2.3 Parameters that nfluence the mass transfer Vapor pressure, gas-phase mass transfer coeffcent and dffuson/desorpton rate of the organc compounds are affected by the temperature of the ar nsde the chamber. Thus, temperature nsde the chamber test must be controlled and recorded durng the entre experment due to the fact that ncrease n temperature cause ncrease n the emssons of VOCs. However, t should be envsaged that fast evaporaton from surfaces results n coolng the surface, thus lowerng the rate of emsson. Ar change rate s another parameter that plays an mportant role to the chamber concentraton. Ar change rate s expressed n how many change per hour of the ar s exchanged at the unt of tme 12

(n/h). If lower concentratons n the chamber test occur due to an ncrease of ar change rate, the evaporatve mass transfer (external dffuson) may ncrease affectng the emsson rate (ASTM D5116-10). Ar velocty can be mportant for the evaporatve controlled emssons. In general the hgher velocty leads to ncreased gas-phase mass transfer coeffcent. Because ths gudance s dealng wth products used ndoors, the test should be done under typcal ndoor veloctes, where applcable and relevant. 2.4 Selecton of test chamber The key element n the selecton of the approprate test chamber s the objectve of the emsson testng. If qualtatve nformaton of emttng volatle compounds s requred varous extracton technques may be appled accordng to product type wthout the use of a test chamber. The extracton can be dynamc headspace samplng, purge-and-trap, solvent or thermal extracton technques. If the extracton technque s valdated t may also provde sem-quanttatve nformaton of the content of volatles; ths may be useful for a conservatve exposure assessment under standardzed condtons n a gven scenaro. Furthermore, mass spectrometrc technques may provde addtonal nformaton about the content of non-volatles compounds. Hstorcally, test chambers from a few cm 3 up to several m 3 have been used for quanttatve emsson testng and determnaton of the emsson rate of buldng materals accordng to ISO and ASTM standards. A number of comparsons and round robn tests have been carred out durng the last two decades. Generally, the test perod has been wthn three and 28 days, or beyond accordng to the objectve. For consumer products the tme frame of nterest has a dfferent focus. Peak emsson rates (concentratons), whch usually occur wthn 0 to 60 mn after the applcaton of a temporary source (e.g. wndow cleaner), are used for the assessment of acute exposure and assocated acute effects. Averaged emsson rates, that are determned by extended samplng duraton, e.g. 6 hours, may be used for the assessment of longer-term exposures and assocated health effects. For constant sources (e.g. passve ar freshener) a constant emsson rate s acheved that may be used for both acute and longer-term exposure assessments. There are several parameters that may nfluence the outcome of the emsson testng apart from those dscussed above. Among those are two major ssues, chamber sze and applcaton or condtonng of the product before startng the test: Chamber sze determnes how the product can be appled. The smaller the chamber the more dffcult to prepare the test specmen, n partcular spray products wthn the chamber. Thus, for small chambers and fast decay emssons that there s a need for outsde sample preparaton specal care should be taken to mnmze emsson losses outsde For small chambers temperature control may be dffcult durng candle testng, thus unntentonal ncrease of the emsson rate may occur. For chambers of 1 m 3 and larger an electronc devce can control the dosage for spray products. 13

The applcaton and condtonng can be carred wthn a full scale (walk-n) chamber. The larger a chamber, the more becomes effectve mxng an ssue for achevng exact emsson data versus realstc scenaro condtons. Further advantages (+) and dsadvantages (-) of chamber sze are lsted below. Small chambers (< 0.1 m 3 ) + Provde basc nformaton of emtted compounds + Relatvely easy to operate + Heatng may be possble + Hgh throughput - Inadequate condtonng (emsson loss durng applcaton and transport to chamber) for wet, lqud and pasty products - Inadequate loadng versus ar exchange rate - Vapor pressure effects that may suppress the emsson (saturaton),.e. lmted transfer capablty - Dffcult to transfer/model emsson rate data for exposure assessment - Dffcult to test sprays under certan use scenaro ( e.g. sprayng nto the ar) Large chambers (0.1 2 m 3 ) + Spray products may be appled nsde chambers 1 m 3 + Relatvely easy to operate (larger chamber are expensve) + Medum throughput - Inadequate condtonng (emsson loss f applcaton outsde and transport to chamber) for wet, lqud and pasty products - Compounds may be lost by excessve dluton (too low concentratons) - Compounds may be underestmated due to wall snk effects - Modellng requred for exposure assessment. Modellng of breathng zone concentratons mght be dffcult, durng and after applcaton - Larger chambers are expensve Full scale (walk-n) chambers (real test rooms) + Allow realstc user behavor, condtonng and loadng wthn chamber under controlled condtons + Provde realstc envronment and concentraton + Data be drectly translatonal to exposure assessment + Personal exposure montorng possble + Ar velocty more realstc than n smaller chambers - Compounds may be lost due to dluton (too low concentratons) - Compounds may be underestmated due to wall and other present surfaces snk effects - Effectve mxng can be a problem, however realstc, and possbly crtcal for representatve samplng - Expensve and may be dffcult to operate - Low throughput 2.4.1. Addtonal consderatons In the selecton of the test chamber one has to ensure that undesred effects that may nfluence the concentratons of the compounds are mnmal. Such effects can be: 14

adsorpton/deposton of the compounds on the chamber walls and other present surfaces and materals, re-emsson from the chamber wall of the deposted compound, chemcal reacton of reactve VOCs wth nlet oxdants (e.g. ozone) may form secondary VOCs. Nevertheless the selected test chamber has to conform to ISO 16000-9 wth respect to recovery and snk effects of the VOCs measured. In addton t s recommended that the test chambers are addtonally tested wth a prescrbed source profle of the VOCs under nvestgaton to check for possble nfluence of the above mentoned effects. The VOC source profle needs to reflect to a certan extent the emsson profle that s usually found n the product class under nvestgaton. For example for products that can be consdered as contnuous emttng sources the constant source could be the rght choce. For products that are consdered sources wth temporary (short-term) emsson patterns t mght be advsable to use nstantaneous pattern. 2.5 The preparaton phase for testng The testng preparaton phase conssts of the followng three (3) levels: - Start-up condtons - Intal test chamber condtons - Product specfc applcaton procedure 2.5.1 Start-up condtons The test chamber start-up condtons n the EPHECT consumer product testng procedures are the same as those reported n ISO 16000-9 (Indoor Ar Part 9: determnaton of the emsson of volatle organc compounds from buldng products and furnshng emsson test chamber method). Ths mples the nstallaton settngs summarzed n Table 2.1. The lsted parameters have been measured or set before the experment takes place and wll be kept constant durng the experment. Table 2.1 Start-up condtons for consumer product emsson testng accordng to ISO 16000-9. Aspect Condtons Ar supply The emsson test chamber has facltes capable of contnuously controllng the ar change rate at a fxed value wth an accuracy of ± 5% Ar flow The devaton of the exhaust flow wth the ntake flow s < 5% Ar Exchange rate Sample collecton lmt 0.5/h The sum of samplng ar flows can be up to 80% of the ntake flow 15

Recovery and snk Ar velocty Usng a permeaton of dffuson tube, nsert a known concentraton of toluene and n-dodecane n the chamber, measure the concentraton after 72h n the room. The recovery should be > 80% The ar velocty above the sample s 0.1-0.3 m/s (accuracy 0.1 m/s) (wth an averagng tme of 10 mnute)* *) In general, ar velocty s not a well-defned parameter and whch comes less relevant n full-scale chambers 2.5.2 Intal test condtons The ntal test condtons are also establshed n agreement wth ISO 16000-9. In consumer product testng these condtons are labeled as ntal condtons, snce the emsson tests of certan products may alter ntal condtons. Ths could for nstance occur when assessng the emssons of a dluted floor cleanng agent: applyng the product n the chamber wll ncrease the relatve humdty that was ntally set at 50%. They are, however, consderng beng less crtcal when realstc user scenaro s smulated. Table 2.2 summarzes the ntal test condtons for consumer product testng. Aspect Temperature Condtons 23 C ± 2 C (accuracy of 1.0 C) Relatve humdty 50% ± 5% (accuracy of 3%) Supply ar & background concentratons (TVOC and VOCS) The concentraton of TVOC s below 20 µg.m -3 ; Indvdual VOCs occur at concentratons below 2 µg.m -3 (Radello code 130 at least 48h, maxmal 5 days) Durng the experments, temperature, relatve humdty and ar flow rate are montored contnuously. 2.5.3 Product specfc test chamber condtons All emsson data measured n the test chamber are recalculated to the deal room dmensons (CEN/TS 16516 and CEN TC 351 WG2). Ths mples a room wth a total volume of 30 m 3, and an ar change rate of 0.5 h -1. Ths deal room conssts of a floor of 12 m 2, a celng of 12 m 2, one door of 1.6 m 2, walls of 31.4 m 2 (excludng door and wndow) and jonts (or small surfaces) of 0.2 m 2. Table 2.3 shows an overvew of these dmensons. For the wndows, reference s made to l Arrêté sur l étquettage NOR : DEVL1104875A and CEN TC 351 WG2, wth a surface of one wndow equal to 2 m 2. In case a product can be used on several types of surfaces, the most mportant surface wll be taken nto account (n agreement wth NOR: DEVL1104875A). Usng the dmensons of ths deal room n the generaton of emsson data, wll also enable us to refer to EU LCI values. However, a drect comparson should be carred out wth some cauton, because LCI values refer to the emsson after 28 days only. Further, LCI values do not necessarly refer to acute effects and respratory 16

dseases. Furthermore, t s probable that LCI values n the future wll consder multple-source contrbuton. Whenever applcable, the loadng factors, related to the deal room dmensons, are respected n the EPHECT test protocols. Ths mples that e.g. a floor cleanng agent wll be tested respectng a loadng factor of 0.4 m 2 /m 3 and a wndow cleanng agent wll be appled respectng a loadng factor of 0.07 m 2 /m 3. Products to be appled on surfaces (other than floor, celng, door, wndow or walls) wll be tested respectng the loadng factor ncluded n Table 2.3 as jonts or small surfaces, as far as ths s a representatve loadng factor for the use of that product n a room. Table 2.3 The deal room dmensons and loadng factors accordng to CEN TC 351 WG2 and CEN/TS 16516 Surface Loadng factor [m 2 ] [m 2 /m 3 ] Floor 12 0.4 Celng 12 0.4 1 door 1.6 0.05 1 wndow 2 0.07 Walls (excl. wndow & door) 31.4 1 Jonts (or small surfaces) 0.2 0.007 Because the major nfluence of the aggregaton state on the use and use scenaro of a product, the frst dvson s made nto lqud and sold consumer and personal care products. Lqud consumer and personal care products Lqud consumer and personal care products nclude fluds, creams and gels. Dependng of the product purpose, they can be found n dfferent packages. They can be stored (1) n a flask, (2) n a spray bottle (pstol spray, contnuous spray or automatc spray), or (3) n a format to be volatlzed. The test protocol scenaros, proposed n the EPHECT umbrella depend on ths product package. All 3 optons are dscussed below n detal: Products packed n a flask Lqud products, stored n a flask, may nvolve products to be used n a dluted as well as n an undluted concentraton. They are typcally appled on a surface. The type of surface on whch the product s tested should be a representatve materal, typcal for the purpose of the product. Throughout the EPHECT project, smlar products tested n more than one lab wll be tested on the same surface materal. However, for full scale chambers, a metal surface (steel) may be preferable to be able to obtan an even surface. After the applcaton, the surface may need to be rnsed. For practcal purposes an addtonal rnsng process after surface dryng wll nterfere n a full scale experment. Thus, data obtaned from full scale testng mght be consdered a worst case scenaro, 17

because there s no nformaton about the rnsng effect. For small chamber testng both applcaton and eventually rnsng may have to be carred out outsde the chamber. The nterpretaton from outsde condtonng should be carred out wth cauton due to lost volatles. EPHECT consumer and personal care products on whch ths secton apples are all purpose cleaners, ktchen cleanng agent, floor cleanng agent, (no spray) wndow cleaner, (no spray) bathroom cleanng agent, (no spray) furnture polsh and floor polsh. It s evdent that condtonng outsde the chamber results n some loss of volatle compounds. Thus, the applcaton should be well prepared and the tme before nserton nto the chamber should be mnmzed as much as possble. Ideally, such testng should be carred out n full scale chambers. In the long run, dedcated applcaton procedures (and test condtons) should be elaborated beyond those n the umbrella for each product type. Table 2.4 gves an overvew of the condtons for emsson testng of lquds, stored n a flask. Table 2.4 Expermental condtons for lquds, packed n a flask Aspect Condtons Loadng factor In agreement wth Table 2.3 Quantty If dluted use: dluton accordng to the results from the market study on EU uses and use patterns [Johnson et al 2012] and accordng to expected (T)VOC levels *. If undluted use: quantty accordng to the results from the market study on EU uses and use patterns [Johnson et al 2012] and accordng to expected (T)VOC levels *. Scenaro Rnse f use scenaro prescrbes to do so Wet mop n or out room * Ths s chamber sze dependent and mples that the used quantty may be multpled f a frst test leads to values below the detecton lmts of the samplng technques. After the experments the loadng factor should be taken nto account. Products packed n a spray bottle Lqud products packed n a spray bottle wll, dependng on the product purpose, be sprayed n the ar or on a surface. The type of sprayng bottle, and thus the use scenaro, wll be related to the product purpose. Products to be sprayed on a surface are packed n a pstol spray bottle; products to be sprayed n the ar wll be packed n a bottle to allow contnuous or automatc (wth electrcty supply) sprayng. In order to avod sprayng on the test chamber walls, the allowed the test chamber dmensons to study these products are restrcted to 0.5 m 3 or larger. EPHECT consumer and personal care products, on whch ths secton apples are ar freshener sprays (manual spray or automatc spray), har stylng products (sprays), deodorant sprays, coatng product sprays, and perfumes. 18

Table 2.5 gves an overvew of the condtons for emsson testng of lquds, packed n a spray bottle. Table 2.5 Expermental condtons for lquds, packed n a spray bottle Aspect Condtons Loadng factor If sprayng pstol (to be sprayed on a surface) n agreement wth Table 2.3 Quantty If sprayng n the ar: spray quantty s lmted to 0.5 g of product ( 0.5 s of sprayng (per m 3 test chamber), or one automatc spray at maxmum capacty) and accordng to expected (T)VOC levels *. If sprayng on a surface: quantty accordng to the results from the market study on EU uses and use patterns (WP5) and accordng to expected (T)VOC levels *. The product s weghed before and after the testng (accuracy. Montorng PM montorng Scenaro Representatve selecton of the surface materal to be sprayed on. * Ths s chamber sze dependent and mples that the used quantty may be multpled f a frst test leads to values below the detecton lmts of the technques. After the experments the loadng factor should be taken nto account. Products packed to be volatlzed Products to be volatlzed can be passve unts that volatlze wthout any user nteracton, or actve unts that requre a source of heatng. Both types of products, packed to be volatlzed, need tme to equlbrate wth the surroundng ar, before any assessment of the product emssons can take place. In EPHECT, ths perod to equlbrate s set on 3 hours (equal to 1.5 ar changes). The only restrcton on test chamber dmensons s the sze of the product to be tested that should ft nto the chamber. EPHECT consumer and personal care products, on whch ths secton apples, are passve and electrc unts. These unts may be ar freshener unts as well as nsect repellent devces. Error! Reference source not found. gves an overvew of the test condtons for lqud products, packed to be volatlzed. Aspect Loadng factor Quantty Condtons Not applcable If passve unt: not applcable If actve unt: poston max The product s weght before and after the experment (accuracy. 19

Montorng Scenaro Partcle montorng durng testng when actve unts Actve unts may need electrc supply n the exposure chamber Sold consumer and personal care products Sold consumer products, consdered n EPHECT, are candles. Ths strategy s based on avalable open lterature (Derud et al. 2012), and on the AISE candle emsson test protocol (Petry et al., 2013). The candle should be nserted n the test chamber, large enough to avod unntentonal temperature ncrease, wth the ar flow on and should be lghted n absence from nstructons from the manufacturer wth a gas lghter or preferably an electrc one (no pollutants). Then the test chamber must be closed. The candle emssons expected to equlbrate durng 3 hours. Samplng however starts n the perod of 0h to 3h after lghtng the candle. The samplng s performed n the followng three hours. When the last samplng hour starts, the candle should be extngushed, and the emssons are montored durng one more hour. For small test chambers the ar flow should be 0.5 m³/h per candle. It should be noted however that n the EPHECT testng hgher flows led to smlar outcome. In case of large test chambers an ar exchange rate of 0.5 h -1 should be used. The ar velocty (speed) n the test chamber n the vcnty of the candle should be measured wthout the candle beng lghted and should be lower than 0.30 m/s. The ar velocty (speed) wth a lghted candle s hgher, due to the convecton movements caused by the thermal gradents. The only restrcton on test chamber dmensons s the sze of the product to be tested. For candle emssons specal attenton should be gven to relatve humdty and oxygen supply. Relatve humdty should be kept below 75%, n order to avod wall condensaton n the chamber (AISE protocol for candle emsson). The outlet oxygen concentraton should not decrease more than 2.5% compared to the nlet oxygen concentraton (AISE protocol for candle emsson). Table 2.7 shows an overvew of the expermental condtons to test candle emssons. Table 2.7 Expermental condtons to test sold products; candle emssons Aspect Loadng factor Condtons not applcable Quantty 1 candle; more than one takng nto account expected (T)VOC levels *. The product s weght before and after the experment. Montorng Scenaro PM montorng EC/OC assessment O 2 montorng at nlet and outlet Rel. humdty The candle s placed on a precondtoned surface n the test chamber. It s lghted n absence of nstructons by the manufacturer by a gas lghter or preferably an electrc one and then set to equlbrate. 20

* Ths mples that the quantty may be multpled f a frst test leads to values below the detecton lmts of the used technques. After the experments the loadng factor should be taken nto account. 2.6 Testng and Samplng phase The gudance deals specfcally wth ar measurements of volatle compounds that are measured by analytcal methods. However, emsson profles have been studed n pre-screenng experments, pror to proposng the measurement patterns. The ar samplng takes place durng predefned tme ntervals wth specfc samplng tme (DTS). The samplng measurement pattern s llustrated n Fgure 2.2. Fgure 2.2 The test chamber concentraton measurements pattern Each samplng s completed n tme DT (hrs): DT =DTIN +DTS where DTIN s the preparaton tme for the samplng to follow, DTS s the samplng tme (hrs), CM s the measured concentraton wthn the tme step DTS. The preparaton tme DTIN needs to be as short as possble, preferably controlled wthout openng the chamber door and dsturb the equlbrum n the test chamber. It s also recommended to apply a predefned and constant samplng tme to mnmze the overall uncertanty. 21

The samplng tme DTS should be as short as possble to allow for hgh samplng frequency, at least at the ntal stage of the testng, but also long enough tme to allow for relable analyss, otherwse the analytcal uncertanty ncreases. Ths may be relevant n full-scale chambers. The measured concentraton CM s the tme averaged concentraton wthn the samplng tme DTS. However for emsson estmatons t s mportant to approxmate CM wth the concentraton at a partcular tme wthn DTS,.e. to the tme DTS/2. Ths approxmaton can be vald when DTS 1. where λ s the ar exchange rate of the test chamber (1/hr). The tme nterval DT should be as short as practcally possble wthn the analytcal capablty. It s better to keep t constant n prncple, although t s recommended to be shorter n the ntal phase to show the progresson of the emsson tme profle. For example, settng 1 hour tme nterval, one could go to ½ hour nterval for the 1st and 2nd tme step. The deal could be also DT 1 A practcal proposal from the EPHECT Project experence s: DTS 1/ 6hrs (.e. 10 mn-keep t the same all the way). DT(1) = DT(2)= 0.5 hrs. Other tme steps: 1 hr (and constant). 2.7 Test Duraton The test duraton s an mportant parameter to estmate more accurately emssons. The vsual nspecton of the measured concentraton tme profle mght ndcate the testng tme adequacy as ths s dscussed below. For ths purpose, we dstngush between two knds of product types: products that are consdered as nearly constant emttng sources (e.g. passve and plug-n ar fresheners), products that are consdered as sources wth temporary (short-term) emsson patterns. Nearly constant emttng sources The deal product here s the one that emts wth a constant rate. In a test chamber wth no deposton the deal concentraton tme profle s shown n Fgure 2.3. There s an ntal transton phase of the order of (2/λ) hours wth ncreasng concentraton. For longer tmes the concentraton remans nearly constant. It s notced that any concentraton varablty n tmes well beyond the transton tme can be attrbuted to varable emsson rate and the possblty of pollutant decay due to chemcal actvty, wall deposton, or pollutant gan due to wall re-emsson. 22

Fgure 2.3 The deal concentraton tme profle for a constant emttng source Thus the duraton of the test needs to exceed the ntal transton tme to ensure to capture the constant level of the emsson,.e. quas-equlbrum has been obtaned n the chamber. The EPHECT project expermental experence has shown that deally constant emsson rate hardly exsts due to the way the product s emttng. Thus, one needs to check carefully on case by case the valdty of constant emsson assumpton. Sources wth temporary (short-term) emsson patterns. Here, t s mportant the duraton of the emsson test to be long enough to be able to reach the zero emsson tme doman. Ths would provde: more accurate estmaton of the (total) emsson better dentfcaton and possbly quantfcaton of addtonal compound decay due to deposton or other snk effects avod addtonal assumptons to extrapolate for the emsson beyond the duraton of the emsson test A sem-logarthmc plot of the concentraton tme dstrbuton together wth the zero emsson slope lne, reveals f the duraton of the emsson test was long enough to reach the zero emsson regme. 23

Ktchen cleanng agent test Ktchen cleanng agent test Measurements Zero emsson slope (a) (b) Fgure 2.4 (logarthmc) test chamber measured lmonene concentraton tme profle from a ktchen cleanng agent. The zero emsson slope lne s the lne gven by the equaton C( t) C0 exp( t) It descrbes the concentraton profle n a test chamber wth ventlaton rate λ n whch the ntal pollutant concentraton s C 0 (an arbtrary number n our case) and the emsson rate s zero. Ideally the tme concentraton profle tends to be parallel to the zero emsson slope lne as the emsson rate decays. In other words, one needs to check how parallel to the zero emsson slope lne s the last part of the concentraton curve. If t s parallel or nearly parallel then the emsson rate has reached practcally the zero value. If ts slope s less than the slope of the zero emsson lne the emsson perssts. If ts slope s greater than the slope of the zero emsson lne ths means that there s pollutant removal wthn the chamber (.e. deposton or reacton). Fgures 2.4 (a) and (b) show the tme concentraton curves of lmonene emtted from the same ktchen cleanng agent from two dfferent chambers. In both fgures the zero emsson slope lne s also plotted. Fgure 2.4 (a) shows that the slope of the pollutant concentraton near the end of the curve s less than the slope of the zero emsson lne whch means that duraton of the test was not long enough. In Fgure 2.4 (b) the slope of the pollutant concentraton curve near the end, s slghtly greater than the slope of the zero emsson lne whch means that the duraton of the test was adequate. In the latter case however there s a systematc trend n the data of ndcatng a slght pollutant removal wthn the chamber. 24

Another way of checkng the testng duraton adequacy s to take the values of the last two concentraton measurements CM(N) and CM(N-1) and calculate the so called emsson strength factor N for the last tme step as follows: N 1 T CM ( N) CM ( N 1) If 0 then the product contnues to emt beyond the testng tme. Longer testng tme s N requred. If 0 the product has ceased to emt below the capablty of the analytcal method. N If 0 the compound at least durng the last tme step s decayng wthn the chamber wth a N decay constant. d N 1 In the case of the test of Fgure 2.4 (b) t was estmated 0.04hr. If the duraton of the test s too short, repeated testng s requred wth a longer test duraton. If the product s appled to a surface t mght be also advsable nstead of ncreasng the test duraton to reduce the product mass wthout volatng the recommended loadng. It s ndcated from the ntercomparson studes of a ktchen cleanng agent that the reducton of the materal thckness ncreases the emsson rate consderably, thus provdng total emsson estmatons wth a shorter test duraton. (Stranger et al, 2013). d 25

CHAPTER 3: EPHECT ANALYTICAL METHODS For each compound to be dentfed, ncludng the EPHECT prorty compound, the detals on the analytcal method for compound dentfcaton and quantfcaton s establshed. An overvew of the methods s shown n Table 3.1. Table 3.1 Overvew of the analytcal methods Terpenods: Tenax TA tubes C6-C16 ISO 16000-6 Lmonene TD GC MS alpha-pnene sample max. 5 l; 20-200 ml/mn geranol column: apolar (95%-5%) a-terpneol calbraton: methanolc soluton of these compounds; spke +/- 5 µl on Tenax lnalool tube Aldehydes: samplng on DNPH tubes; ISO 16000-3 formaldehyde acrolen glutaraldehyde acetaldehyde check effectve samplng range (Waters booklet): 50 l for 10-1000 ppb calbraton wth hydrazon standards analyss: HPLC-UV or DAD Aromates: Benzene toluene xylenes Styrene PAHs: naphthalene & benz-a-pyrene Dsnfectants: chloroamnes hypochlorte (H 2 O 2 ) See terpenods ISO 16000-12: not possble for test chamber samples Alternatve: PDMS/Tenax 150 ml/mn 60 mn; TD-GC-MS wth cold trap for hgh bolers Hery et al. (1995) samplng on flter cassette (Teflon flter and 2 mpregnated flters wth As 2 O 2 and Na 2 CO 3 ); 1 l/mn; 2 hours; IC; result = sum of chloroamnes + ClO - Mcl. compounds (not assocated wth respratory dseases) PCBs PCDDs Phthalates Isothazolnones see PAHs CO NH 3 NO 2 NDIR montor method: EN 14626; or contnuous low cost logger Both methods need calbraton Samplng on Orbo 554 tubes (conform OSHA method ID-188 Analyss: on selectve electrode 26

Slanes/sloxanes/polymers +/- fluornated Quaternary ammonum chlordes (QUATs) ISO 16000-15: short term measurements; contnuous analytcal montor chemo lumnescence ISO7996; alternatve manual photometrc reference methods wth mpnger (Saltzman method) ISO 6768 1. Samplng on tenax tubes (see terpenods) and analyss by GC-MS/MS usng both EI and CI. 2. Samplng on quartz flters (e.g. Whatman Grade GF/C - 1.2 um retenton, Cat No. 1822-025). Extracton of flters by PLE and subsequent analyss of extracts by LC-MS Samplng on quartz flters e.g. (Whatman Grade GF/C - 1.2 um retenton, Cat No. 1822-025). Extracton of flters by PLE and subsequent analyss of extracts by LC-MS. Partcles (spray and combustble products only) Prmary aerosols: Optcal method (Grmm), aerodynamc and electrc moblty (TSI, Dekat). Sze dstrbuton, concentraton or partcle number Secondary aerosol flter samplng 27

CHAPTER 4: EMISSION ESTIMATIONS 4.1. Basc Theory The estmaton of the emssons from a test chamber experment s obtaned from the emtted compound mass balance under the basc assumpton that the concentraton of the emtted compound wthn the test chamber s unform. Otherwse one has to use more sophstcated modelng tools such as Computatonal Flud Dynamcs (CFD) tools to estmate the emssons. The most general form of the mass balance equaton n test chambers s gven n Equaton 4.1 (Kephalopoulos (1999), Salthammer (2009)) dc V ER( t) F Qout C Qn Cext A D V X (4.1) dt where: C: Concentraton n the Chamber (mass unts/m³) V r : Volume of the test chamber (m³) ER: Emsson Rate (mass unts/h) F: Removal Rate by an ar cleanng devce n the chamber (mass unts/h) Q out : Ar flow rate gong out of the chamber (m³/h) Q n : Ar flow rate gong n of the chamber (m³/h) C ext : Concentraton of the nlet ar (mass unt/m³) A ds : Rate of adsorpton on surfaces n the chamber (mass unts/h) D: Rate of desorpton from surfaces n the chamber (mass unts/h) X: Rate of generaton/destructon through chemcal reactons n the chamber (mass unts/m³/h) In the remander t s assumed that the test chamber experment s arranged n such a way that the emtted compound nlet concentraton, removal and desorpton as well as chemcal actvty are neglgble. In ths case Equaton 4.1 s smplfed as follows dc dt ER( t) C V It s notced that Equaton (4.2) s equvalent to the one utlsed n ASTM D5116-10 Standard. The measured concentraton feld s utlsed n Equaton 4.2 to obtan estmaton of emssons. For ths purpose we can dstngush the followng cases: (4.2) 28

Case I: Constant emsson rate In ths case Equaton (4.2) has an analytcal soluton ER C( t) (1 exp( t)) (4.3) V Any measured concentraton CM t ) at the tme nterval Fgure 2.2) can be used to estmate the constant ER: ( DTS DTS t t t (see 2 2 ER V CM ( t ) [1 e t e DTS 2 e DTS DTS 2 ] (4.4) For DTS 1 ths equaton s smplfed: t ER V CM ( t ) [1 e ] (4.5) Case II: Varable emsson rate The basc assumpton that s made for emsson modelng purposes s that the concentraton values obtaned n the tme nterval from t -DTS/2 to t +DTS/2 equals the concentraton value at the tme t (see Fgure 2.2). As t has been dscussed before, such an assumpton s qute vald when λ DTS << 1 (λ s the test chamber ventlaton rate). In ths case the concentraton pattern utlzed for the modelng s shown n Fgure 4.1. 29

Fgure 4.1 The measured concentraton smplfed pattern. In ths case Eq (4.2) becomes at tme t : dcm dt ER V CM (4.6) Emsson rate estmaton -Opton I Followng the ASTM standards (ASTM D5116 10) the numercal soluton of Equaton (4.3) yelds: CM ER( t) V ( CM ) (4.7a) t CM t [( CM CM 1 ) / t 1 (CM 1 CM ) / t ] / 2 (4.7b) Such a model n order to be suffcently relable needs a dense number of measurement ponts whch cannot be always the case n ths type of measurements (.e samplng and analyss). Emsson rate estmaton -Opton II A less demandng and more accurate approach s to ntegrate Equaton (4.6) over each CM 1 CM ER( t ) V ( CT ) (4.8) t t : 30

where 1 ER ( t ) ER( t) dt s the average emsson rate over t t t 1 CT ( t ) C( t) dt s the average concentraton over t whch can be approxmated t as follows: t CM CM 1 CT ( t ) (4.8a) 2 Emsson rate estmaton -Opton III If the tme steps the tme nterval t are short enough so that one can assume that the emsson rate wthn t does not vary consderably and t can be assumed constant the average emsson rate can be estmated analytcally drectly from Equaton (4.6): E( t ) CM CM 1 λv 1 IE IE (4.9) IE exp( Δt ) (4.9a) Total emsson estmaton If TIMTEST s the total testng tme duraton and N the last tme step and ET the total emsson durng TIMTEST the ntegraton of Equaton (4.6) over test duraton TIMTEST gves : ET V [ CM N TIMTEST CT ( TIMTEST )] (4.10) where 1 CT ( TIMTEST ) C( t) dt (4.10a) TIMTEST TIMTEST Equaton (4.10) can be smplfed f CM N TIMTEST CT (TIMTEST ) or CM 0 In ths case N ET V TIMTEST CT (TIMTEST)] (4.11) The concentraton CT(TIMTEST ) s obtaned from the numercal ntegraton of the Equaton (4.10a). 31

It s recommended the CT(TIMTEST) to be drectly measured by samplng the whole testng perod. If ths s the case the total emsson s then drectly measured by applyng Equatons (4.10) or (4.11). It s recommended for qualty assurance purposes CT (TIMTEST ) to be estmated by both methods. Case IIa: Varable emsson rate as exponental decay functon Equatons (4.7), (4.8), (4.9), (4.10) and (4.11) are vald for any varable emsson rate provded that the measurements tme ntervals are small enough and suffcent enough so that the nduced numercal errors are not prohbtvely hgh. If these condtons are not met but t can be proved that the emsson rate s decayng approxmately exponentally, one can follow the ASTM Standards [ ] and estmate the emsson rate as follows: Express emsson rate as an exponentally decayng functon: ER kt ( t) ER0 e (4.12) where ER 0 = the peak emsson rate (at tme t = 0) [μg h -1 ], k = the decay rate constant [h 1 ]. The concentraton dstrbuton as a functon of the emsson rate s gven by the equaton: CM kt e t e k ER0 (4.13) V The measured concentratons n Εq. (4.13) are utlzed to estmate the unknowns ΕR 0 and k by non-lnear regresson analyss. One has to be careful wth the selecton of the ntal values of the unknowns. Followng the ASTM-D5116 nstructons the ntal value for k s gven by the Equaton: k e t max k (4.14) where t max s the tme of maxmum observed concentraton. 32

Fnally, the total emsson s estmated by the followng equaton: ER0 ET [μg] (4.15) k 4.2. Emsson Estmatons Once the measurements and the sample analyss are completed the emssons can be estmated utlsng the above mentoned basc theory. The followng steps can be followed to obtan such emssons. 1 st step: Plot the measured concentraton tme profle n sem-logarthmc scale and normal scale. Based on expert judgement and what t has been dscussed above, check f the profle makes sense wth respect to product and compound tested. 2 nd step: Check vsually the above concentraton tme profle graphs and followng the dscusson n Chapter 2, try to assocate t wth one of the three followng categores: Profles ndcatve of constant or nearly constant emsson source Profles ndcatve of contnuous varable emsson source Profles ndcatve of decayng emsson source 3 rd step : Estmate emssons for the category selected as follows: Constant or nearly constant emsson source In ths case the concentraton profle for constant behavor. t 2/ shows constant or approxmately Theoretcally a sngle concentraton selected from the ones measured, s adequate to estmate the constant emsson rate ER by usng Equaton (4.5) or even (4.4). It s however recommended to take the maxmum measured concentraton apply Equaton (4.5).e. [ CM ] and max t ER V CM ] [1 e ] (4.16) [ max Concernng the dentfcaton of the characterstc emsson parameters: - If the product undergoes relatvely sgnfcant mass loss durng the applcaton t s plausble to characterse ts emsson by the specfc emsson rate n terms of the product mass loss (m).e. 33

g SER( ) hr gr ER m (4.17) - If the mass loss of the product durng the applcaton proves to be nsgnfcant t s more plausble to express SER n terms of the emttng product surface (A).e. g SER( ) 2 hr m ER A (4.18) Contnuous varable emsson source In ths case the concentraton profle for t 2/ shows a relatvely sgnfcant varaton wthout a clear declne trend. For the emsson rate estmaton, t s recommended to apply Equaton (4.8) as explaned n secton 4.1 Once the emsson rate s estmated as a functon of tme one can proceed wth the dervaton of the characterstc emsson parameters. It s notced that such an emsson behavour s most probably suggestng consderable mass loss of the product. Therefore t s plausble to characterse ts emsson by the specfc emsson rate n terms of the product mass loss (m).e. g SER( ) hr gr ER m For better representatveness t s plausble to express emsson n terms of average specfc emsson rate. By applyng Equaton (4.8) we obtan: 1 SER SER( t ) t TIMTEST TIMTEST (4.19) Equaton (4.13) can be exploted for exposure estmatons snce t s related drectly to the compound mass release wthn TIMTEST. It s advsable TIMTEST to be of the order of exposure tme or even longer. For short tme exposure (.e. one hour or less) t s advsable to consder the peak specfc emsson rate [ SER( t )] by utlzng Equaton (4.8) max Decayng emsson source In ths category the emtted compound s released nto the ar n relatvely short tme. 34

It ncludes ether sprays drectly released nto the ar or product materal (lqud/gel/spray) appled to a surface. In a test chamber experment the total emsson s derved from Equaton (4.10) or (4.11). In the specal case of exponentally decayng emsson t can be derved from Equaton (4.15) For exposure estmatons t s obvous that one has to work wth specfc total emsson wth respect to product mass whch s proportonal to the emtted compound content.e. g SET ( ) gr ET m For sprays drectly released to the ar ths quantty s enough. It s notced that the release tme here lasts a few seconds. For exposure tmes of half hour and more the release tme s too small compared wth exposure tme. Ths means that we can treat n our exposure calculatons the total emsson as an nstantaneous release. For a consumer product appled to a surface one mght thnk for the need of the emsson rates. Our lmted experence n EPHECT has shown that the emsson rates are senstve to the applcaton condtons. In other words, for the same product brand, the same emtted compound, but dfferent applcaton, n terms of mass, surface area, preparaton phase etc we mght have emsson tmes lastng from mnutes to several hours. Defntely more research wll be needed to come to more refned conclusons. At ths stage for exposure studes t s recommended where t s feasble, the estmated total emsson to be treated as nstantaneous release for the calculatons. In that case emsson rates are not needed. Otherwse the emsson rate can be estmated from the varous optons gven above.e. Equatons (4.7), (4.8), (4.9) and (4.13). For exposure estmatons the most preferable s Equaton (4.13) provded that the exponental decay assumpton s vald. Ths approach makes the possble exposure parametrc studes relatvely easy snce the emsson rate s defned by only two parameters: total emsson and emsson decay rate. Equaton (4.8) s the next choce snce t s expected to ntroduce lower numercal errors due to relatvely lmted number of concentraton measurements. 35

CHAPTER 5: CONCLUDING REMARKS AND FUTURE CONSIDERATIONS Wthn the EPHECT Project a systematc study on the consumer products emssons has started and the assocated dffcultes and uncertantes have been explored. The exstng knowledge on the subject has been collected and assessed, a relatvely large amount of expermental data have been produced and analysed and the relatve mportance to human exposure has been studed. A comprehensve gudance has been produced on emsson testng that ncludes: test chamber selecton and preparaton, product applcaton, pollutant samplng and analyss, test duraton, emsson estmaton methodology and parameterzaton. The concentraton pattern produced by the test chamber experment aganst the expected behavour as explaned n the present gudance, may reveal to a large extent possble test chamber or/and measurement caveats. Based on the measured concentraton pattern, recommendatons are gven on selectng the proper modellng opton for emsson estmaton as well as the proper emsson parameterzaton for exposure studes. Lmted Intercomparson studes have ndcated the uncertanty on certan emsson parameters on specfc products although further systematc work s strongly needed. The experence collected from the EPHECT Project has ndcated further work at least n the followng ssues. On emsson estmaton The present gudance addresses manly the problem of emssons from consumer products to be estmated from a dscontnuous concentraton pattern n a test chamber. Such temporalty s expected to generate numercal errors. The present proposed emsson estmaton methodology tres manly to reduce those numercal errors. Nevertheless, t s desrable the concentratons to be measured contnuously f ths s possble. Otherwse t s proposed to nvestgate a new dscontnuous pattern as ndcated n Fgure 5.1. 36

Fgure 5.1 The proposed new measurement concentraton pattern n a chamber test. It s proposed to sample n addton over the entre t,.e. to provde expermental values for CT t ) (see Equaton 4.8). Then ER t ) can be estmated drectly from the experment usng ( ( Equaton 4.8 wthout any numercal approxmaton. There s a need to nvestgate to what extent the dfferences of the expermental errors n the short and long tme samplng may affect the qualty of the results. On emsson representatveness In the above emsson estmatons from the test chamber concentraton measurements the crtcal queston remans n what degree the estmated emssons can be appled n the real world wth dfferent room volumes, ar exchange rates, background concentratons from other sources, and user scenaros, and ncludng the presence of oxdants. The ambton up to ths pont was to express emssons n terms of sutable emsson factors that may be drectly utlzed nto real applcatons and exposure estmatons n real envronments. However an extensve parametrc testng and comparson s requred coverng expected ranges at least n use scenaros, chamber volumes, ar exchange rates and room temperatures. Ths extensve testng s needed to be accompaned by detaled 3-D transent computatonal modellng that consders the mportant emsson release, transport and removal mechansms of the emtted compounds. Such an effort s expected to provde the methods and the tools to translate sngle test chamber measurements nto real world emssons wth the ntenton to assess personal exposure. Further to ths, models are needed to establsh the personal breathng zone exposure n realstc settngs. 37