Although any architectural project must ensure the safety and well-being of its occupants, this goal is especially pertinent for healthcare spaces, whose primary occupants are those prone to getting sick or worsening their initial condition. For this reason, its design must not only support medical procedures in their optimal conditions, but also ensure that the environment is kept sterile and clean at all times.
How do materials that fight the growth of pathogenic bacteria work? Is it possible to improve the hygiene and healthiness of an environment without neglecting the aesthetics of the space? We address this question by reviewing the case of Krion® solid surfaces, widely used in the healthcare sector but also in residential, commercial and office projects.
In layman’s terms, bacteria are the most abundant microorganisms on planet Earth. They grow in all kinds of environments, and some can even survive in outer space. Although most bacteria provide benefits to humans and the environment, there are also pathogenic bacteria that cause infectious diseases, usually respiratory, intestinal, and contagious. To reduce the risk of infection, our environment must be as antiseptic as possible - that is, its materials must inhibit the fixation of bacteria and avoid the formation of bacterial biofilms that can make us sick.
The surfaces and elements that make up the spaces we inhabit can easily house bacteria of all kinds, and their level of adherence depends directly on their physical and chemical composition. From our own cell phones to door handles, to our desks and food handling counters, an interior space is full of bio-contaminated places. And although hand washing and disinfecting surfaces be effective in mitigating the spread of these bacteria, choosing the right materials can further enhance the health and hygiene of the place we live in.
For this purpose, homogeneous surfaces, without pores and with antibacterial properties, are widely used in hospital rooms, where the level of sanitation must be as high as possible. However, concern for the aesthetic or environmental quality of interior spaces encompasses most projects, a goal that hospital interiors cannot avoid despite their other necessary functions.
Krion® solid surface, for example, is a smooth material to the touch, similar to natural stone, which includes advanced properties that prevent the growth of bacteria and fungi. It is made up of two thirds of alumina trihydrate (ATH) powder – of high chemical purity – and one third advanced monomers, in addition to other additives that favor its application in sanitary interiors. As it is manufactured both in large format plates and in thermoformed shapes, it allows large continuous surfaces to be coated without noticeable joints, avoiding the absorption of liquids and the accumulation of pathogens in these spaces and providing a clean aesthetic.
This type of solid surface can be used on interior and exterior walls, and in the design of furniture such as countertops, work desks, and equipment for bathrooms and kitchens. In all these applications, surfaces can be easily cleaned while effectively resisting concentrated acids, such as sulfuric or hydrochloric acid, or the chemicals present in cleaners or disinfectants. In the specific case of healthcare projects, they can even withstand contact with X-ray developer fluid, Wright's stain, methylene blue, betadine, or blood.
There are additives that provide antibacterial properties to the different materials, releasing chemical agents from the surface to attack circulating bacteria or grafting them onto it to prevent the adherence of bacteria to the surface.  However, the REACH regulation (Registration, Evaluation, Authorization and Restriction of Chemicals) has identified 161 substances present in additives that could be considered potentially harmful to health or the environment, such as Bisphenol A. It is important, then, to analyze the composition of the available materials and products, and to prefer those that present antibacterial properties based on their own composition, as we previously identified on certain solid surfaces. Products composed of intrinsically antibacterial metals – such as silver, copper, gold, and zinc – have been shown to be equally effective in this regard.
The minerals present in some surfaces can even react to sunlight, allowing them to come into contact with the humidity and oxygen in the environment. This process, called Photocatalysis, releases a series of molecules that can bind to the polluting particles, generating complex molecules that do not harm humans.
The benefits of antibacterial materials apply to all types of projects and, due to their variety of finishes, colors, and textures, they are increasingly being applied in residential interiors, and even in cultural buildings, hotels, restaurants, and public spaces. In any of the cases, we always recommend investigating the components of the specified materials and products, placing special emphasis on scientific tests and trials that ensure their effective action against pathogenic microorganisms, in accordance with various international standards.
 D. Sun, M. Babar Shahzad, M.Li, G. Wang, and D. Xu. (2015). Antimicrobial Materials with Medical Applications. Research Gate. Available here.