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Media information  TOTO Europe

23. Juli 2020

What to do about the “toilet water” cloud?

A recent test showed that rimless toilets with special flush technology can prevent the spread of aerosols in the bathroom.

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Effective protection from viruses and bacteria starts in your own bathroom. According to Hygiene Professor Klaus-Dieter Zastrow, rimless toilets featuring a special flush technology can help prevent the spread of aerosol particles – protecting people from potential infections.

Our own bathroom, especially the toilet, is a place where we feel comfortable – and we assume that it is clean. In fact, it is a major source of germs and bacteria. Experts are especially concerned about so-called aerosols – tiny droplets in the air that help to spread germs, which can then cause respiratory infections.

But how do these aerosols make their way into the bathroom? Nearly every commercially available toilet has a toilet bowl with a rim. Anyone who has cleaned a toilet knows that this rim is a critical part of the toilet. It’s difficult to clean underneath this rim with a brush and cloth, and impossible to see what dirt or waste is left behind – even after thorough cleaning. Hygiene Professor Klaus-Dieter Zastrow examined this specific issue, and discovered that the area below the rim is a kind of “reservoir” of germs and viruses. Experts are also concerned about the type of flush found in conventional toilets: Tiny droplets containing germs can spray beyond the edge of the toilet, and remain suspended in air for a short period of time – enough time for people to inhale them.

Women’s magazine Brigitte provided a more dramatic description based on a study conducted by the Medical Center at New York University. According to Brigitte, conventional toilets produce aerosols when flushed – and these combine to form a “toilet water cloud” that spreads out into the surrounding area. If the door is closed or ventilation in the bathroom is poor, it is possible that people could inhale these aerosols – which could in turn cause infections.

Do more than just lowering the lid – stunning test results

While Brigitte advises simply lowering the toilet lid, Zastrow has discovered a more elegant solution: The hygiene specialist has spent many years researching how to improve hygiene in highly critical areas such as hospitals and care units. In 2014, he took a closer look at conventional toilets and discovered the area below the toilet bowl rim as one source of infection. Zastrow conducted a new series of tests on toilets in June 2020 and found a number of results that deserve some attention. He examined innovative toilets that lack the problematic rim around the toilet bowl, and use a different flush technology – one that creates a circulating whirlpool of water.

Hygiene a priority in Japan – looking at their developments makes sense

One provider of rimless toilets is TOTO, a sanitary ware manufacturer with a special focus on hygiene. TOTO’s European headquarters are located in Düsseldorf, and the company is based in Japan – widely considered a model country when it comes to hygiene. For this reason, it makes sense to look at their developments. Zastrow examined two of the company’s newest toilets, paying extra attention to the innovative “circulating” flush technology: He reported: “This flush creates a circulating whirlpool of water that washes every square centimetre of the toilet bowl several times. The flush water swirls in a circle. This movement keeps the water inside the toilet. One could say that the whirlpool created by the flush spreads fewer bacteria in the bathroom. As a result, this type of toilet is especially well-suited for use in hospitals,” Zastrow continued. And things that help in the hospital could also be helpful at home. The study also closely inspected whether or not droplets had settled on the previously cleaned, high-gloss polished floor surrounding the toilet after flushing, as this would indicate the formation of aerosol particles. The hygiene specialist was able to confirm: “The aerosols that are produced by conventional toilets from time to time are not an issue for rimless toilets.”

When discussing the tested toilets, Zastrow also answered a question regarding whether or not coronaviruses behave the same as the germs he used in the study. From his point of view, there is no difference: “Coronaviruses are part of the stool, which means that there is no difference. They are washed away like all other bacteria.”

Link to the interview with Hygiene Professor Klaus-Dieter Zastrow:

About TOTO Europe

TOTO, one of the world’s leading sanitary ware companies, has an unwavering focus on people and their well-being. Established in Kitakyushu, Japan in 1917, TOTO has been developing, producing and marketing its comprehensive high-end bathroom concepts for the European market since 2009. The company aims to create a new attitude towards life through regeneration, comfort and hygiene, integrating technologies into their product designs in a smart, nearly invisible way. Japan’s leading manufacturer in the sector, TOTO offers a comprehensive range of products including ceramic sanitary ware, faucets and accessories. In 2020, the company looked back on 40 years of developing and manufacturing its renowned WASHLET™. TOTO supports the development of a fully emission-free society and is very committed to sustainability: By joining the RE100 initiative, TOTO Group will convert all of its facilities to power from sustainable energy sources by the year 2040. The company also received certification from the Science Based Targets Initiative (SBT) to reduce greenhouse gases in line with the Paris Agreement, and to systematically cut CO2 emissions further on this basis. TOTO employs 30,000 people world-wide.

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