IN an era of Covid-19 and increasing awareness of hygiene issues, The Tile Association (TTA) and its members are promoting the hygiene advantages of correctly installed tiled surfaces, especially in commercial kitchens and food preparation environments. Ceramic tiled surfaces are entirely safe to install and use in hygiene sensitive installations, particularly if large format glazed or porcelain tiles are used with epoxy grouted joints.
TTA has collaborated earlier this year with ASCER and Confindustria Ceramica (representing the Spanish and Italian ceramic tile industries respectively) on a campaign to promote the benefits of ceramic tiled surfaces compared to alternatives across Europe. Entitled ‘But ceramic…is a safe choice’, the campaign employed social media and digital communication to promote the benefits of tiled surfaces, especially in flooring, with regard to hygiene, ease of cleaning, waterproofing, fire resistance and sustainability.
Meanwhile tile manufacturers are continuing to develop new tiles with anti-bacterial or anti-microbial additives. Anti-bacterial self-cleaning tiles provide the strongest protection and act against the most common bacteria. They work best in the presence of natural or artificial light and are suitable for a wide range of different applications.
Research carried out by the Tile Council of North America in 2019 compared the performance of Plastic Based Products (PBM), which includes Luxury Vinyl Tiles (LVT) and other resilient floorcoverings. It found the PBM products allowed significant water leakage, using an established industry test, compared to ceramic tiles. This in turn can provide an environment underneath the floorings in which mould and fungi are able to develop.
The products tested were claimed by their manufacturers to be 100% waterproof and to be suitable for wet areas. However, once the moisture leaks under the flooring, mould can occur. This mould can be a cause of structural damage, discolouration and unpleasant odours, but also the WHO has identified invisible mould (such as under a floor) as a leading cause of sickness, allergy and respiratory complaints. The ceramic tiles in the American testing permitted no mould growth.
Testing carried out in Europe by the Fraunhofer Institute also found a tendency for microbial growth at higher temperatures, and water leakage tests detected microbial concentrations on the underside of the tested LVT.
It’s been alleged that a tiled surface has a level of porosity which can harbour bacteria and that the grout lines are a weak point due to the supposition that they aren’t impervious.
Ceramic glazed surfaces and porcelain tiles are, in fact, to all intents and purposes impervious, with less than 0.5 per cent porosity, as are epoxy grouts, to the extent that some have been approved for use in nuclear power stations, since they can be decontaminated from radioactivity.
Provided British Standards are followed during installation, tiled surfaces are very safe. The relevant standards are BS EN 14411:2012, which covers the specification of ceramic wall and floor tiles, including their resistance to abrasion and chemicals. BS 5385-4:2015 includes a code of practice for the design and installation of ceramic and mosaic tiling in specific conditions.
This gives recommendations on design considerations and on the installation of ceramic wall and floor tiling and mosaics in situations where there are specific environmental or functional requirements, eg sterile conditions, wet areas, and conditions that are potentially detrimental to either or both the installation or the background, such as chemical attack.
The grouts used should conform to BS 13888, which covers the specification, conformity and evaluation of all types of tile grout.
Fully vitrified tiles and epoxy resin-based grouts are not porous and have been recommended in hygienic applications such as commercial kitchens for many years. The use of tiles and epoxy grout is consistent with Guidelines published by Campden & Chorleywood Food Research Association, which, following its own research, concluded that ‘the grouted joints and texture did not compromise the cleanabilities of tiled surfaces’. The research also states that the cleanability of tiled surfaces with grouted joints is not compromised over that of tiles alone.
Grouted areas in a tiled surface will normally only amount to about 3% of the total area in any case and, if epoxy grouts are used, this surface will be totally impervious and will not harbour bacteria, provided an appropriate cleaning regime is employed.
Ceramic tiled surfaces can safely be cleaned at temperatures well in excess of 60deg C, since tiles are fired to temperatures far above that during the manufacturing process, eg porcelain which is fired at 1260deg C. This means tiles are a good solution in an environment where boiling liquids might accidentally get spilt on them.
Establishing a correct cleaning regime is of course critically important, and TTA is about to launch a new technical publication on the subject of ‘Cleaning & Maintenance of Wall & Floor Tiles’.
In wet areas, or where an aggressive cleaning regime is required, such as in hygiene sensitive environments, there is a further benefit of ceramic tiled surfaces – a liquid-applied or sheet waterproofing membrane can be installed behind the tiles as a tanking system. If a tile is damaged then the background, when tanked, remains fully protected and the waterproofing element is maintained.
Another area that the TTA has been working on is that of slip resistance of tiled surfaces, and it offers a technical publication on ‘Slip Resistance of Hard Flooring’. No ceramic tiles are inherently slippery when clean and dry, but the slip resistance of any type of floor covering can significantly reduce if it becomes contaminated by any form of lubricant, such as water or dust, depending upon the floor’s surface texture and footwear used.
Ceramic tiles are available with a range of textures to improve slip resistance in wet environments, such as swimming pool surrounds, food processing areas, breweries and similar locations. TTA also has a slip resistance testing facility for tiles at its Stone, Staffordshire, head office.