EN 16845-1:2017

Photocatalysis - Anti-soiling chemical activity using adsorbed organics under solid/solid conditions - Part 1: Dyes on porous surfaces

This European Standard specifies a test method for the evaluation of the photocatalytic self-cleaning performance of materials showing photocatalytic activity, usually based on semiconducting metal oxides such as titanium dioxide, by the measurement under solid/solid conditions of the decolouring ability under irradiation with ultraviolet light (UV-A) of a test sample on which a dye solution is sprayed and dried.
This European Standard is intended for use with opaque and rough surfaces of different kinds, such as construction materials in flat sheet, board or plate shape, that are the basic forms of materials for various applications.
This European Standard also applies to fabric, plastic or composites containing photocatalytic materials that are not soluble in acetone. This European Standard does not apply to photocatalytic glass, granular materials (unless they are deposited in compact films or layers over flat solid surface) and flat non porous materials.
The method evaluates only the self-cleaning ability of the material under ultraviolet light irradiation. It cannot be applicable to evaluate other performance attributes of photocatalytic materials, i.e. decomposition of water contaminants in liquid or gas phases contacting the material, and antifogging and antibacterial actions.

Photokatalyse - Schmutzabweisende, chemische Aktivität unter Verwendung adsorbierender organischer Stoffe im Zustand fest/fest - Teil 1: Farbstoffe auf porösen Oberflächen

Diese Europäische Norm legt ein Prüfverfahren für die Bewertung der photokatalytischen Selbstreinigungs¬wirkung von Materialien mit photokatalytischer Aktivität fest, üblicherweise auf Basis von halbleitenden Metalloxiden, z. B. Titandioxid, durch Messung der Entfärbungsfähigkeit bei Bestrahlung mit UV-Licht (UV-A) einer mit einer Farbstofflösung besprühten und getrockneten Probe unter fest/fest-Bedingungen.
Diese Europäische Norm ist zur Anwendung bei opaken rauen Oberflächen verschiedener Art vorgesehen, z. B. Baustoffe in Form von Blechen, Brettern oder Platten, die die Grundformen von Materialien für ver-schiedene Anwendungen darstellen.
Diese Europäische Norm gilt außerdem für Gewebe, Kunststoffe oder Verbundstoffe, die photokatalytische Materialien enthalten, die in Aceton nicht löslich sind. Diese Europäische Norm gilt nicht für photo¬kata-lytisches Glas, photokatalytische Granulate (außer sie wurden als Kompaktfolie oder kompakte Schicht auf einer flachen, festen Oberfläche aufgetragen) und flache, nichtporöse photokatalytische Materialien.
Das Verfahren bewertet nur die Selbstreinigungsfähigkeit des Materials bei Bestrahlung mit UV-Licht. Es kann nicht angewendet werden, um andere Leistungsattribute photokatalytischer Materialien zu bewerten, d. h. Zersetzung von Wasserverunreinigungen in flüssigen oder gasförmigen Phasen, die mit dem Material in Berührung kommen, und Antibeschlagwirkung und antibakterielle Wirkung.

Photocatalyse - Activité chimique anti-salissures à l’aide de matières organiques adsorbées dans des conditions solide/solide - Partie 1 : Colorants sur des surfaces poreuses

La présente Norme européenne spécifie une méthode d’essai pour l’évaluation de la performance d’auto-nettoyage photocatalytique des matériaux présentant une activité photocatalytique, reposant généralement sur des oxydes métalliques semi-conducteurs comme le dioxyde de titane, par mesure dans des conditions solide/solide de la capacité de décoloration sous irradiation avec de la lumière ultraviolette (UV-A) d’un échantillon d’essai sur lequel une solution de colorant est pulvérisée et séchée.
La présente Norme européenne est destinée à être utilisée pour des surfaces opaques et rugueuses de différents types, comme les matériaux de construction sous forme de tôles plates, de panneaux ou de plaques, c’est-à-dire les formes de base des matériaux destinés à diverses applications.
La présente Norme européenne s’applique également aux tissus, plastiques ou composites contenant des matériaux photocatalytiques qui ne sont pas solubles dans l’acétone. La présente Norme européenne ne s’applique pas au verre photocatalytique, aux matériaux granulaires (sauf s’ils sont déposés en films ou couches compacts sur une surface solide plane) et aux matériaux non poreux plats.
La méthode évalue uniquement la capacité auto-nettoyante du matériau sous irradiation à la lumière ultraviolette. Elle ne peut pas être appliquée pour évaluer d’autres attributs de performance des matériaux photocatalytiques, à savoir la décomposition des polluants de l’eau en phase liquide ou gazeuse en contact avec le matériau, ou les actions anti-buée et anti-bactérienne.

Fotokataliza - Kemično ukrepanje proti onesnaženju z uporabo adsorbiranih organskih snovi v pogojih trden/trden - 1. del: Barvila na poroznih površinah

Ta evropski standard določa preskusno metodo za ocenjevanje fotokatalitskih samočistilnih lastnosti materialov, ki izkazujejo fotokatalitsko dejavnost, običajno na podlagi polprevodniških kovinskih oksidov, kot je titanov dioksid, in sicer z merjenjem zmožnosti razbarvanja preskusnega vzorca pri osvetlitvi z ultravijolično svetlobo (UV-A), predhodno obarvanega z barvno raztopino in posušenega, v pogojih trden/trden. Ta evropski standard je namenjen za uporabo pri različnih neprosojnih in grobih površinah, kot so gradbeni materiali v ploski ali ploščati obliki, ki sta osnovni obliki materialov za različne načine uporabe. Ta evropski standard se uporablja tudi za tekstilije, plastiko ali kompozite, ki vsebujejo fotokatalitske materiale, netopne v acetonu. Ta evropski standard se ne uporablja za fotokatalitsko steklo, sipke materiale (če niso naneseni v kompaktnih slojih ali plasteh na ravno trdno površino) in za ravne neporozne materiale. Metoda ocenjuje zgolj samočistilno zmožnost materiala pri obsevanju z ultravijolično svetlobo. Ne more se uporabljati za ocenjevanje drugih zmogljivosti fotokatalitskih materialov, npr. razkrajanje vodnih onesnaževalcev v tekočih ali plinskih fazah, ki vsebujejo material, ter protizamegljevalne in antibakterijske učinke.

General Information

• Status: Published
• Publication Date: 28-Feb-2017
• Withdrawal Date: 29-Sep-2017
• ICS: 25.220.20 - Surface treatment
• Technical Committee: CEN/TC 386 - Photocatalysis
• Drafting Committee: CEN/TC 386/WG 4 - Self cleaning applications
• Current Stage: 9093 - Decision to confirm - Review Enquiry
• Start Date: 13-Jul-2023
• Completion Date: 14-Apr-2025
• Ref Project: SIST EN 16845-1:2017 - Photocatalysis - Anti-soiling chemical activity using adsorbed organics under solid/solid conditions - Part 1: Dyes on porous surfaces

EN 16845-1:2017 - Photocatalysis (Dyes on porous surfaces)

Overview

• Standard reference: EN 16845-1:2017 (CEN)
• Title: Photocatalysis - Anti-soiling chemical activity using adsorbed organics under solid/solid conditions - Part 1: Dyes on porous surfaces
• Purpose: Defines a laboratory test method to evaluate the photocatalytic self‑cleaning performance of materials (typically TiO2-based semiconducting metal oxides) by measuring UV‑A driven decolouring of sprayed dyes on porous/opaque surfaces.
• Scope highlights: Intended for opaque, rough and porous construction materials, plus fabrics, plastics or composites containing photocatalytic particles that are insoluble in acetone. Excludes photocatalytic glass, non‑porous flats and loose granular materials unless formed into compact layers.

Key Topics and Requirements

• Test principle: A controlled dye solution (volatile solvent, typically acetone) is sprayed and dried on the sample surface under solid/solid conditions. UV‑A irradiation is applied and the reduction in dye (decolouring) is tracked using reflectance spectroscopy.
• Measured outputs: Kinetic evaluation of dye disappearance expressed as dye half‑life (τ1/2) and related parameters such as the dirt parameter (DP), deposition rate (DR), covered area (CA) and the dirt‑parameter calibration function linking reflectance to dye loading.
• Instrumentation & controls: Requires a reproducible spraying system (spray gun, fixed spraying distance and timed flow), diffuse reflectance spectrometer for visible spectra, calibrated light source (UV‑A), and controlled sample support and environmental conditions.
• Dyes referenced: Examples include Metanil Yellow, Rhodamine B and Methylene Blue; the test recommends selecting the dye with maximum optical contrast for the specific material.
• Limitations: Method evaluates only UV‑driven surface self‑cleaning. It does not assess photocatalytic activity in liquid/gas phase pollutant degradation, antifogging, antibacterial functions or properties of non‑applicable substrates.

Applications - Who Uses This Standard

• Manufacturers of photocatalytic coatings, façade panels, tiles, construction boards, treated textiles and composite materials for product development and quality control.
• Testing & certification laboratories performing performance verification and comparative assessments of self‑cleaning materials.
• Specifiers and architects seeking standardized evidence of UV‑driven anti‑soiling performance for building materials.
• R&D teams evaluating photocatalyst formulations or substrate effects on visible‑soiling removal.

Related Standards

• CEN/TS 16599 - Photocatalysis: irradiation conditions for testing photocatalytic properties
• CEN/TS 16981 - Photocatalysis glossary of terms
• EN ISO/IEC 17025 - Competence of testing and calibration laboratories
• Note: EN 16845 is a multi‑part document; Part 2 covers simulated weathering conditions.

Keywords: EN 16845-1:2017, photocatalysis, self‑cleaning, anti‑soiling, UV‑A, titanium dioxide, porous surfaces, dyes, reflectance spectroscopy, dirt parameter.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.UELUDQLKPhotocatalyse - Activité chimique anti-salissures à l’aide de matières organiques adsorbées dans des conditions solide/solide - Partie 1 : Colorants sur des surfaces poreusesPhotocatalysis - Anti-soiling chemical activity using adsorbed organics under solid/solid conditions - Part 1: Dyes on porous surfaces25.220.20Površinska obdelavaSurface treatmentICS:Ta slovenski standard je istoveten z:EN 16845-1:2017SIST EN 16845-1:2017en,fr,de01-maj-2017SIST EN 16845-1:2017SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 16845-1
March
t r s y ICS
t wä t t rä t r English Version
Photocatalysis æ Antiæsoiling chemical activity using solid conditions æ Part
sã Dyes on porous surfaces Photocatalyse æ Activité chimique antiæsalissures à l 5aide de matières organiques adsorbées dans des surfaces poreuses
Photokatalyse æ Schmutzabweisendeá chemische Aktivität unter Verwendung adsorbierender Farbstoffe auf porösen Oberflächen This European Standard was approved by CEN on
s v November
t r s xä
egulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterationä Upætoædate lists and bibliographical references concerning such national standards may be obtained on application to the CENæCENELEC Management Centre or to any CEN memberä
translation under the responsibility of a CEN member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN members are the national standards bodies of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Serbiaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Avenue Marnix 17,
B-1000 Brussels
t r s y CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Membersä Refä Noä EN
s x z v wæ sã t r s y ESIST EN 16845-1:2017

Typical Experimental Data . 21 A.1 General . 21 A.2 Optimization of the Spraying Conditions (example) . 21 A.3 Measurement of the Spraying Mass Flows (example) . 22 A.4 Measurement of the Covered Area (example) . 23 A.5 Evaluation of the Dirt Parameter Calibration Function (example) . 25 A.6 Evaluation of the Self-cleaning Effect (example) . 27 Bibliography . 29
UVVISIR radiation 3.3 spraying distance distance from the outlet of the spraying gun (see experimental setup) and the surface of the test sample SIST EN 16845-1:2017

·
13,5% of the maximum intensity 3.5 dirt parameter DP dye amount spread or persistent over the sample surface 3.6 dirt parameter calibration function mathematical function that describes the relation between the Dirt Parameter and the amount of dye spread over the sample surface 4 Symbols and abbreviations a, b, c polynomial constant parameters obtained by the fit using Formula (7) Anet
CA Covered Area (cm2) Cdye concentration of the dye in the spraying solution (g cm–3) dac density of acetone at the temperature of the measurement (g cm–3) DP dirt parameter (nm): the parameter is indexed depending on the context DR deposition rate (g s–1 cm «2) f volumetric spraying flow (cm3 s–1) Fi mass flow (g s «1) kdye first order kinetic constant of the specified dye for the photocatalytic self-cleaning process (min–1) MW molecular weight n number of steps used for deposition of the dye on the sample surface; typically, n = 5, but can be larger if the surface is excessively wet
spei and j referring to steps of spraying and illumination, respectively Rbackground
SC standard dye covering defined in Table 2 (g cm «2) T temperature in °C ti irradiation time in min tspr spraying time (s), calculated as tspr = sprstdt/n W the full width at half maximum (FWHM) of the sprayed dye colour peak (cm)
average covering of dye at the surface (g cm–2); indexes i and j refer to steps of spraying and illumination, respectively o maximum average covering of dye at the surface (g cm–2), obtained at sprstdt SIST EN 16845-1:2017

wavelength (nm) max wavelength (nm) at which there is a maximum of absorbance sprstdt standard spraying time (s) τ1/2dye half-life of the dye for the photocatalytic self-cleaning process (min) 5 Principle This standard concerns the comparison and the quality assurance of photocatalytic materials used as self-cleaning materials. The method described is intended to measure the photocatalytic self-cleaning performance of a photocatalytic material by evaluating its ability to clean its surface, previously covered by a known amount of coloured organic compound, as a consequence of the exposition to ultraviolet light. A controlled amount of a dye solution dissolved in a volatile solvent (acetone) is spread on the tested surface by using a spraying gun. The photocatalytic material turns out to be covered by the solid dye. The relation between the amount of the spread dye and the spectrophotometric reflectance is defined in the calibration step. The calibration function involves the measurement of the reflectance spectra of the sample surface as a function of the dyes covering. Dyes used in separate experiments are Metanil Yellow, Rhodamine B, and Methylene Blue. The test shall be carried out with the dye showing the maximum optical contrast with the material to be tested. Criteria for the choice of the best dye are here given (see 8.3.2). Optionally, the test can be carried out with the others dyes as the reactivity of each dye can depend on the specimen. The measurement with more than one dye is encouraged, but it is not compulsory. The self-cleaning activity measured by this test shall be referred to the used dye. The soiled surface is then irradiated in air by UV-A light under defined conditions and the decrease of the dye amount on the surface is monitored by measuring the reflectance spectra of the surface of the test sample in the visible range. By using the calibration function the change of the reflectance spectra can be related to the kinetic of disappearance of the dye from the surface. The photocatalytic self-cleaning performance is determined as the half-life (minutes) of the dyes applied to the surface. 6 Instruments 6.1 Spraying system The method described in this standard relies on the possibility to cover the sample surface with the dye in a controlled way. A spraying system shall be used to spread over the sample surface a solution of the dye (dye solution) in volatile solvent (acetone). The spraying system consists of a sample support and in a pneumatic system under pressure able to spray the dye solution over the sample for different definite times. The dye solution shall be spread by using a spraying gun that forms a circular spot. This involves a normal (Gaussian) distribution of the amount of dye centred in the spot of the dye on the surface. The amount of solution spread over the test sample is controlled by changing the spraying time (tspr) with a timer that opens and closes, with a precision of ± 0,01 s, the dye solution flow. The relative distance and orientation between the gun and the sample shall be changed in a way to obtain a symmetric covering of the surface of the test sample and the desired surface covered area. Due to the normal distribution of the colour intensity at the test piece surface, the dye surface covered area is defined as the area of the sample where the colour intensity is
·
% of the maximum intensity (see 8.2). The optimal distance from the gun outlet to the surface of the test sample is referred as the spraying distance. A sketch of the pneumatic spraying system and of the sample support is shown in Figure 1 and Figure 2. SIST EN 16845-1:2017

Key A (N2) actuator gas line (N2) A air atomization AIR A tressurized bottles Aw water Ad dye/dyes solution B spraying gun 123 digital timer EV electrovalve GR gas regulator with manometer GT gastap pair pressurized AIR S sample V(N2) vent gas line (N2) Figure 1 — Pneumatic spraying system SIST EN 16845-1:2017

Key A position of the spraying gun B sample arrows forward or back, up or down translation of the sample position Figure 2 — Sample support The spraying distance between the gun and the sample (see Figure 2) is typically fixed after setup of the instrumentation (see 8.2); the test samples are placed orthogonally to the spraying flow direction. The spraying gun shall provide a circular sprayed spot. Using a 0,8 mm fluid nozzle orifice under the given pressure, the typical spray distance is 200 mm. Typically, the fluid flow through the gun shall be regulated to obtain a value close to 0,2 cm3 s–1. For the accurate measurement of the spraying flow see 8.2.2. The atomization air flow is typically (270 ± 20) N dm3 min–1. The system shall be operated under a ventilated chemical hood. Safety precautions shall be taken for use of acetone (CAS No: 67-64-1) such as safety glasses, good ventilation, removal of sources of ignition from the working area. 6.2 Analytical balance An analytical balance with the precision of 10 «4 g is used for all the gravimetric operations. SIST EN 16845-1:2017

¶ 3 nm. The reflectance spectra are measured by using a diffuse reflectance standard such as BaSO4 as a reference of 100 % reflectance material. 6.4 Light source The light source should agree with CEN/TS 16599. It shall provide UV-A irradiation within a wavelength range of 345 nm to 385 nm for a specimen containing TiO2. Suitable sources include the so-called black light (BL) and black light blue (BLB) fluorescent lamps, with a maximum at 351 nm or 368 nm, and xenon arc lamps with optical filters that block radiation below 345 nm. In the case of xenon arc lamp, a cooling system shall be used. The test sample shall be irradiated uniformly. The distance between the light source and the sample shall be adjusted so that the UV irradiance (300 nm to 400 nm) at the sample surface is (20 ± 0,5) W m–2. A UV radiometer in conformity with CEN/TS 16599 shall be put at the same distance as the surface of the test sample to be tested. The irradiance along the length of the test sample shall also be constant within ± 5 %. The temperature of the sample during the test shall be (25 ± 5) °C. 6.5 Other experimental needs a) A bottle with a neck diameter larger than the spot dye spot size, as determined under b) in 8.2.3. b) Ventilated chemical hood. c) Sonication bath. d) Safety glasses. e) Vial (from 20 ml to 30 ml in
volume) for use in a) and c) in 8.2.3. 7 Materials 7.1 Dyes used Three different dyes can be used in the test (see Table 1). The dyes shall be dissolved in acetone (2-propanone), a volatile organic solvent that allows a perfect solubilisation of the dyes. The dyes have different optical contrast on the test sample depending on their colour. When a dye is chosen, a calibration function shall be performed (see 8.3). Depending on the effective test sample chromatic properties and the obtained calibration function, the proper dye is selected. SIST EN 16845-1:2017

· 7 cm x 7 cm) or circular (diameter
· 7 cm). The thickness of the test sample can changed as it is not relevant. The right distance from the light source to obtain the specified light power intensity as outlined in 6.4, and the right distance from the spraying gun (see below in 8.
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