Description of product tests 5.1. testing and performance

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1 testing and performance 5.1 Testing and performance This section gives an outline of the various tests undertaken to relevant European and international standards, along with the minimum values required by these standards, in accordance with the testing requirements of ISO Description of product tests We are an UNE EN ISO 9001: 2000 certified company, which encompasses design, production, distribution, marketing and sales of ceramic wall and floor tiles. The Porcelanosa laboratories that are in charge of finished product quality control are located inside each production plant. They perform the relevant controls on the raw materials that make up the tile body (clay, feldspar, sand, talcum etc.) as well as finished product testing to determine that all tiles manufactured will comply with relevant technical specifications. Technical reports are made available to our customer service and sales staff, so that they can fully understand the properties of the materials and products that are specified. May 05 technical and samples hotline t:

2 5.1 testing and performance Dimensional control tests Tiles are subjected to an ongoing process of dimensional control, which measures length, width and thickness, as well as the straightness of sides (which detects the deviation of the centre of a tile side from the straight line that connects its vertices on the tile plane; in short, the convexity or concavity of a tile s sides). Tests measure the deviation of rectangularity (or determining if it is not square) and measuring surface planarity, which is subdivided into centre curvature (deviation of the centre from one of a tile s sides with respect to the plane defined by three of its four vertices) and warpage (or deviation of a tile s fourth vertex from the plane define by the other three). Surface quality tests include looking for surface defects and intentional effects. Glossary Nominal measurement: The measurements used to designate the product. Manufacturing measurement: The actual measurements of the tile. Calibre: Each one of the intervals, usually three of the same amplitude, that the manufacturer defines for grouping tiles with the same nominal measurements, whose actual measurements have differences so minor as to be practically irrelevant. Testing standards Tile are tested to the following dimensional control standards: BS EN ISO : 1997, Determination of dimensions and surface quality. Water absorption tests The capacity of a wall or floor tile body to absorb water determines the product s open porosity, i.e. the total volume of outer pores liable to be filled with fluid at atmospheric pressure. The value is expressed as the percentage of the increase in the product s mass with respect to its dry mass after undergoing a standardised process of prolonged immersion in boiling water, when tested in accordance with BS EN ISO , Determination of water absorption. This value will have a direct bearing on other performance characteristics such as mechanical resistance, the resistance to sudden temperature changes and frost resistance. It also gives us an idea of the degree of internal cohesion and compaction of the fired product. The open porosity of a wall or floor tile firstly depends on the composition of the ceramic body. This may vary considerably from one product to another (porcelain floor tiles have low porosity; wall tiles are very porous). Other determining factors include the compaction of an unfired piece or piece-forming (which in turn depends on such other factors as grain size, distribution of the spray-dried powder, moisture etc.) and, finally, the firing process. Water absorption is also used as a criterion for classifying ceramic wall and floor tiles in ISO 13006: Obviously, the glazed layer has zero water absorption since it is fully vitrified. Testing standards Tile are tested to the following water absorption standard: BS EN ISO , Determination of water absorption, apparent porosity, apparent relative density and bulk density. Deviation in surfaces Sample tile is immersed in boiling water Straightness of sides Water absorption test technical and samples hotline t: May 05

3 testing and performance 5.1 Mechanical resistance tests Tiles are tested for their degree of mechanical resistance in the following areas: Impact and compression resistance Bending strength Hardness or scratch resistance Surface abrasion resistance Impact and compression resistance Impact can be defined as the application of a high degree of instantaneous force on a minimal surface, and is generally negative for ceramic products. Heavy or pointed objects falling on tiles may damage or shatter the surface, depending on the type of object, overall mechanical resistance of the tile, and the adhesive and elastic factors involved in the tile-adhesive-substrate system etc. The determination of impact resistance is addressed in the European standard through measuring what is known as the restitution coefficient (BS EN ISO : 1997). Today s ceramic floor tiles, and to a greater extent vitrified tiles, have mechanical resistance ratings that are comparable to those of other inorganic materials (natural stone, marble, terrazzo etc). Bending strength Ceramic materials are fragile in the sense that they break when their bending strength limit is exceeded. Bending strength is determined by following the method stated in the BS EN ISO standard, Determination of bending strength and breakage strength. This consists of using sample tiles under conditions set by the standard, with the breakage load necessary to break tiles expressed in newtons (N); the breakage strength, also expressed in newtons (N) is obtained by multiplying the breakage load and the distance between supports and dividing by tile width; modulus of rupture, expressed at N/mm 2 is obtained by dividing the breakage strength by the minimum thickness along the line of tile breakage. Bending strength is tested by placing samples in the worst possible installation conditions. The device used to measure this value is called a flexometer, comprising a mobile platform on which the sample is placed (on two supporting points, which would never be the case in a real installation) and raising the platform up until it makes contact with the device. A reading of the force withstood by the piece is taken up to the point when it breaks. This gives a measurement of the degree of the product s internal cohesion, which is directly related to the tile s total porosity, the distribution and quantity of vitreous and crystalline phases present, composition, the compaction method used to form the biscuit and firing. In general terms, it can be said that bending strength increases from porous to vitrified products and from extruded to dry-pressed products. Bending strength is an important characteristic that must be included in the design criteria when specifying ceramic tiles based on the level of performance demanded of them; however it is of a secondary importance for wall tiles and is considered as a reference value of their internal cohesion. 19 mm chrome steel ball droppe from a height of one metre abov glazed surface of sample tile 1m Pressure Impact resistance coefficient of restitution Bending strength test via flexometer May 05 technical and samples hotline t:

4 5.1 testing and performance Mechanical resistance tests continued Hardness or scratch resistance Hardness or scratch resistance along with surface abrasion resistance (see below) are interrelated characteristics that indicate a ceramic floor tile s durability to resist the loss of its surface appearance as a result of use. The wear or loss of a tile s surface appearance will depend on the external agent causing the wear and the physical characteristics of the floor tile surface. We can identify the external factors that produce wear on the floor in question: the type of wear by scraping (friction, direction of the scraping, magnitude etc.), the type of mechanical agent (leather, rubber, types, metal etc.), the type of intermediary material between the floor tile and the scraping agent (sand, mud, water, snow, organic matter etc.). Tests for surface hardness or scratch resistance are regulated by the EN 101 standard, putting minerals whose hardness is known into contact with the surface of the piece being tested. The Mohs Scale (see below) is used as the basis of comparison. For wall tiles, this parameter is of very little importance, but for floor tiles, it can be used as a point of reference to predict their ability to withstand surface wear. Mohs Scale The Mohs scale is as follows: Determination of surface abrasion resistance (PEI method) This test is performed in accordance with the method described in the BS EN ISO : 1998 standard: Determination of resistance to surface abrasion for glazed tiles. It covers all all glazed ceramic tiles used for floor covering. In this test, the tile surface is subjected to the action of a rotating abrasive load, consisting of different sized steel balls and an abrasive load of an extremely hard material (corundum second on the Mohs hardness scale only to diamond), with a specific amount of water. This compound is spun sequentially at a specific number of revolutions, and gauged by an abrasion meter that is equipped with an automatic device that stops it after a set number of revolutions. At the end of the test, the tested sample is visually checked against tiles that have not undergone testing in order to determine its classification. Abrasive loads Under BS EN ISO : 1998, the total load on each test specimen consists of: 70.0 g of steel balls of diameter 5 mm 52.5 g of steel balls of diameter 3 mm g of steel balls of diameter 2 mm 8.75 g of white fused aluminium oxide of grain size F 80 according to ISO ml of deionised or distilled water Mineral Moh s hardness Talc 1 Gypsum 2 Calcite 3 Fluorspar 4 Apatite 5 Felspar 6 Quartz 7 Topaz 8 Corundum 9 Diamond 10 technical and samples hotline t: May 05

5 testing and performance 5.1 Classification of glazed ceramic tiles according to their abrasion resistance Glazed tiles are then classified according to the table shown below. This classification is valid for the given applications under normal conditions. Consideration should be given to the footwear, type of traffic and cleaning methods expected, and the floors should be adequately protected against scratching dirt at the entrances to buildings. Classification of glazed ceramic tiles Abrasion stage; Class Typical use failure visible at revolutions Glazed tiles in this class are not recommended for use on floors Floor coverings in areas that are walked on essentially with soft soled footwear or bare feet without scratching dirt (for example residential bathrooms and bedrooms without direct access from the outside) Floor coverings in areas that are walked on by soft soled or normal footwear with, at the most, occasional small amounts of scratching dirt (for example rooms in the living areas of homes but with the exception of kitchens, entrances, and other rooms which may have a lot of traffic). This does not apply to abnormal footwear; for example hobnailed boots. 750, Floor coverings in areas that, with normal footwear, are walked on more often with small amounts of scratching dirt (for example residential kitchens, halls. corridors, balconies, loggias and terraces). This does not apply to abnormal footwear; for example hobnailed boots. 2100, 6000, 4 Floor coverings that are walked on by regular traffic with some 12,000 scratching dirt so that the conditions are more severe than Class 3 (for example entrances, commercial kitchens, hotel, exhibition and sale rooms). >12,000* 5 Floor coverings that are subject to severe pedestrian traffic over sustained periods with some scratching dirt, so that the conditions are the most severe for which glazed floor tiles may be suitable (for example public areas such as shopping centres, airport concourses, hotel foyers, public walkways and industrial applications). * Tiles which have undergone more than 12,000 revolutions must then pass the ISO test for stain resistance on the abraded area of the tile. This approximate classification is given for guidance only (see ISO ). It should not be taken to provide accurate product specifications for specific requirements. BS EN ISO : 1997, Determination of deep abrasion resistance on unglazed tiles (CAPON method) This test consists of subjecting a sample to the wear produced by a 200 mm dia. steel disc, spinning during 150 revolutions with a stream of abrasive material (corundum). The best result is determined by the volume of material removed during the test, which is calculated on the basis of the volume of the material removed. Porcelanosa in-house test: Determination of surface abrasion resistance (method for simulating surface abrasion resistance from continuous use) Porcelanosa believes that the degree of a ceramic tiles resistance to abrasion on its glazed surface is the factor that is going to essentially determine its durability. Therefore an in-house method has been developed to give a clearer idea of how tile samples withstand wear and loss of appearance. This complements the abrasion resistance test performed accordingly to the PEI method and the deep abrasion test (CAPON). The test reproduces and even exaggerates the real abrasion conditions that any floor tiles are subject to. Used as an abrasive agent is a quantity of sand with a high silica content (with a hardness of 7 on Mohs scale), which is placed on the sample. A force equal to a person weighing 80 kg (all of which is channelled through their shoes) is applied. This abrasion of the tile surface is maintained during 10 minutes, after which the extent of the wear is assessed. For this method, a rating scale for abrasion and the loss of appearance produced was established. As with the PEI surface abrasion test and the CAPON deep abrasion test, a representative sample is taken from each production run of a floor tile model and then subjected to this test which simulates the surface abrasion produced by intensive use. Force equal to one person (80kg) is applied Mechanical device rubs back and forth Sand placed on sample tile Determination of surface abrasion resistance (method for simulating surface abrasion resistance from continuous use. May 05 technical and samples hotline t:

6 5.1 testing and performance Mechanical resistance tests continued Determination of crazing resistance (glazed tiles) This test is performed according to BS EN ISO , Determination of Crazing Resistance. Glazed Tiles, which consists of exposing a sample of five tiles to five high-pressure and high-temperature cycles in an autoclave, after which pieces are checked for crazing. Tile surfaces are tinted with a methylene blue solution that helps to detect any defects produced. Summary of mechanical testing standards Tile are tested to the following mechanical resistance standards: BS EN ISO : 1997, Determination of modulus of rupture, and breaking strength. BS EN ISO : 1997, Determination of resistance to deep abrasion for unglazed tiles. BS EN ISO : 1999, Determination of resistance to surface abrasion for glazed tiles. BS EN ISO : 1996, Determination of crazing resistance for glazed tiles. EN 101, Method for determination of scratch hardness of surface according to MOHS. BS EN ISO , Determination of impact resistance by measure of coefficient of restitution. High temperature High pressure Determination of crazing resistance (glazed tiles) technical and samples hotline t: May 05

7 testing and performance 5.1 Chemical resistance This test is carried out according to the method described in BS EN ISO : 1997, Determination of chemical resistance, which consists of applying reactive agents (e.g. ammonium chloride to simulate household cleaners) to the surface of the tile samples (5 for each reactive agent) over a defined period and at room temperature. Testing solutions used Household chemicals: Ammonium chloride solution, 100g/l. Swimming pool salts: Sodium hypochlorite solution 20 mg/l, prepared from technical grade sodium, hypochlorite with about 13% (m/m) of active chloride. Acids and alkalis Low concentrations: Hydrochloric acid solution, 3% (V/V) Citric acid solution 100 g/l Potassium hydroxide solution, 30 g/l Acids and alkalis High concentrations: Hydrochloric acid solution, 18% (V/V) Lactic acid solution 5% (V/V) Potassium hydroxide solution, 100 g/l Procedures for glazed tiles 1. A uniform layer of sealing material is applied to the rim of a cylinder which is turned upside down onto a glazed surface, and seal around the rim. 2. The test solution is then poured through the inlet to a height of 20 mm. Maintain the test assembly at 20 ± 2 C. 3. To test the resistance to household chemicals, swimming pool salts and citric acid, the test solution remains in contact with the test specimen for 24 hours. The cylinder is then removed and the glazed surface cleaned with a suitable solvent to remove the sealing material. 4. To test the resistance to hydrochloric acid and potassium hydroxide, the test solution remains in contact with the test specimen for 4 days. The test assembly is shaken gently once a day ensuring that the level of the test solution does not change. The test solution is replaced after 2 days. After 2 more days the cylinder is removed and the glazed surface cleaned with a suitable solvent to remove the sealing material. Determination of class The tile must be completely dry before assessment can commence. In order to assess whether the pencil test is applicable, draw several lines with the pencil on untreated parts of the glazed surfaces and attempt to remove the marks with a wet cloth. If the pencil marks cannot be removed, the classification system is not applicable and these tiles shall be reported as Normal classification not possible. Reactive agent Glass jar Reactive agent Sealing material 3mm thick Sample tile Testing chemical resistance May 05 technical and samples hotline t:

8 5.1 testing and performance Frost resistance This test is carried out according to the method described in BS EN ISO , Determination of frost resistance. A sample of 10 defect-free tiles (an area of at least 0.25 m 2 ) are vacuumimpregnated. Tiles are then subjected to 100 freeze-thaw cycles in a refrigeration chamber. Each freeze-thaw cycle follows the following procedure: A drop in temperature at a speed no greater than 200 C per hour 15 minutes below 5 C 15 minutes in immersion above 5 C Frost resistance is a property that is only necessary for wall and floor tiles specified for outdoor use in cold climates or for use inside refrigeration chambers. This is a characteristic closely connected with the open porosity of the ceramic body, in which not only is the quantity of these outer pores important, but their size and distribution as well. Condensed moisture and water, that have made their way into a tile, exercise considerable pressure on its structure, causing the piece to break up into flakes or even destroying it completely in successive freeze cycles. It is possible for the damaging effects of frost to extend beyond the tiles themselves, and it may also break part of the grouted joints and adhesives. For other reasons, but also to improve frost protection, the surfaces to be tiled should be waterproofed (in their bonding to the substrate and during the grouting phase) in order to prevent moisture from filtering through from the inside or entering via capillary action from the outside. It is vital that the specifier designates what use the wall or floor tiles are going to be put to, and frost resistance certification should be requested. Testing standards Tile are tested to the following frost resistance standard: BS EN ISO : 1997, Determination of frost resistance Exposure to temperature drops no greater than 20 C per hour mins exposure at -5 C mins exposure at 5 C Determination of crazing resistance (glazed tiles) technical and samples hotline t: May 05

9 testing and performance 5.1 Resistance to staining This test is performed according to the method described in BS EN ISO : 1997, Determination of resistance to stains, which consists of applying a few drops of the following reactive agents on the surface of test pieces (5 for each reactive agent). Determination of the resistance to stains is achieved by maintaining the following test solutions and materials in contact with the tiles for a suitable length of time. Stains leaving a trace (pastes) Green staining agent in light oil Red staining agent in light oil (for green-coloured tiles only) Stains having chemical/oxidizing action Iodine, 13 g/l solution in alcohol. Stains, forming a film Olive oil, according to the definitions of the International Olive Oil Agreement (1079). Following the test, test pieces are then cleaned using the following cleaning methods: The test pieces are visually inspected after each cleaning method are classified according to the following chart: Evaluation Classification Stain removed with Method A 5 Stain removed with Method B 4 Stain removed with Method C 3 Stain removed with Method D 2 Persistent stain 1 Note: Classification 3 is the minimum value established by the ISO 13006: 1998 the standard for the staining resistance of ceramic tiles. Testing standards Tile are tested to the following staining resistance standard: BS EN ISO : 1997, Determination of resistance to staining Cleaning method Method A Method B Method C Method D Description Hot tap water during 5 min and then drying with a damp cloth Manual cleaning using a non-abrasive commercial cleaning agent, rubbing with a non-abrasive sponge. Washing with water and drying with a damp cloth. Mechanical cleaning with a rotary brush and an abrasive commercial cleaning agent, during 2 minutes. Washing with water and drying with a damp cloth. Immersion, during 24 h, in an adequate solvent: 3% HCI solution, KOH solution 100 g/l, acetone or trichlorothylene. Washing with water and drying with a damp cloth. Reactive agent applied Cleaning with water/commercial cleaning agent and damp cloth Determination of resistance to staining May 05 technical and samples hotline t:

10 5.1 testing and performance Other design and performance criteria Ceramic tiles have an intrinsic series of properties that make them ideal for specifying as wall and floor coverings in places with special requirements for hygiene, fire resistance, low electrical conductivity and radiation. Hygienic performance The firing at high temperatures (around 1100 C to 1200 C for ceramic tiles) produces chemical reactions and physical transformations leading to the formation of a hard, compact and resistant inert structure. For this reason, the presence of any micro-organisms can be ruled out, as the temperatures that the product is exposed to during its manufacture make their survival impossible. Ceramic wall and floor tiles, properly installed (with the correct adhesives and grouting materials), represent the most effective and convenient and option for maintaining proper conditions of hygiene and cleanliness. Their impermeable surface prevents the intromission of liquid, vapour, toxic substances and any other contaminating agent, in addition to preventing (due to its non-porosity) the generation of reactions, putrefactions, efflorescence or organic growth. The chemical resistance of ceramic tiles also enables them to withstand without undergoing any alteration cleaning with aggressive detergents and disinfectants that would otherwise be difficult to use on other wall and floor covering materials. Furthermore, given their electrical equipotentially and non-predisposition to the accumulation of electrostatic loads, ceramic tiles contribute to physiological comfort and prevent electrically active airborne dust from being picked up. Effect of fire The fire performance of ceramic materials is evaluated based on the following criteria: The resistance to the destructive action of flames. The possibility of contributing to fire spreading. The emission of smoke or toxic substances. The CEC (European Federation of Ceramic Manufacturers) has carried out an experimental analysis of the fire performance of the different materials currently used as wall and floor coverings, based on the following parameters: Calorific power: Defined as the amount of heat developed in the full combustion of a substance. According to this parameter, only ceramic wall and floor tiles presented full inertia to combustion in the temperature range normally produced in a fire. Oxygen index: This is the minimum concentration of oxygen required to maintain the combustion of a material. Ceramic materials are non-combustible no matter what the oxygen concentration is. Ignition temperature: The temperatures at which a material is set aflame in the presence or absence of a flame, respectively. Once again, ceramic materials proved to be non-combustible. Impermeable surface means vapour and toxic substances are not absorbed. Tiles do not give off any smoke Impermeable surface means liquids are not absorbed. Tiles are non-combustable and do not catch fire Hygienic performance Fire resistance technical and samples hotline t: May 05

11 testing and performance 5.1 Flame development and flame length: Refers to the speed at which the front of the flame advances. Inflammability: Defined as the speed with which the flame on one side of a material is spread to the other. Combustibility: This parameter gauges the heat produced by the combustion of the material and the speed with which it occurs. In these last three parameters, ceramic wall and floor tiles proved to be completely inert to combustion. Density and toxicity of smoke: Smoke is dangerous because it reduces visibility, making it harder to evacuate a burning building. It also poses a risk of asphyxiation and intoxication due to the CO that is present. For example, if the concentration of 0 2 is reduced to 14% and visibility to 20%, the concentration of CO will reach 0.5%. In these conditions, expectations for survival are reduced to less than five minutes. Ceramic wall and floor tiles do not give off any smoke or toxic gases whatsoever, making them the best suited materials (considering their positive performance with the rest of parameters) for homes and public buildings frequented by many people, such as hotels, offices, hospitals, services and commercial areas, entertainment venues etc. Electrical conductivity Ceramic tiles are a classic non-conducting insulator of electrical current. They do not produce an accumulation of electrostatic surface charges. This can significantly contribute to a feeling of physiological relaxation. Carpets and other types of synthetic materials accumulate charges of static electricity, generating discharges through the human body. Colourfastness and effect of light Some substances become altered after prolonged exposure to sunlight. The coloured glazes and ceramic pigments used in the decoration of ceramic wall and floor tiles will not alter in sunlight, regardless of how long they are exposed. Thermal performance Thermal comfort essentially depends on the insulating characteristics and the thermal capacity of the environment s surfaces. Good insulation entails low thermal conductivity limiting the escape of heat in winter, and the inflow of heat from the outside during summer. A high thermal capacity implies that a considerable amount of energy is needed to heat or cool a surface, thereby limiting fluctuations in temperature. The presence of ceramic wall or floor tiles does not have a significant bearing on the aforementioned parameters in evaluating thermal performance. This depends mainly on the building structure and substrates and the type of exterior openings. The only bearing ceramic tiles have is that they increase the mass and thickness of the surface on which they are installed. In the specific case of ventilated facades, energy savings in heat (in winter) and air-conditioning (in summer) can be obtained. Tiles withstand prolonged exposure to sunlight and do not change colour. Colourfastness and effect of light May 05 technical and samples hotline t:

12 5.1 testing and performance Porcelanosa Group Limited t: f: e: Colours shown in this brochure are as accurate as allowed for by the printing process. Actual samples are available on request. Porcelanosa has a policy of continually improving and developing product ranges, and reserves the right to change product specifications, without notice.