Many private homes, hospitals and other healthcare facilities still have conventional toilets with rimmed bowls, and these models continue to be sold today. Hygiene professor Klaus-Dieter Zastrow was Chairman of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute for many years, and is currently working on how to improve hygiene in hospitals. In this context, he identified the area under the rim of toilet bowl as a “reservoir” for viruses and bacteria – an important factor that experts are considering in conjunction with conventional flush technologies: Bacteria can be spread beyond the edge of the toilet bowl in the tiny droplets of spray produced when the toilet is flushed. 

These droplets can then land on the surfaces of the washbasin, other furnishings and floor, presenting a risk of exposure and infection. TOTO brought a newer generation of toilets with rimless bowls to the European market in 2009, and other manufacturers have since followed suit. Zastrow determined that the rimless bowl alone is not enough to prevent infection, and that the formation of aerosols needs to be prevented when the toilet is flushed. In other words, the flush technology used is a critical factor.

In June 2020, the hygiene specialist conducted a study comparing conventional toilets with two rimless toilet bowls from TOTO: the RP and SP models. Among other aspects, he examined the innovative Tornado Flush technology offered in the two TOTO models, which he described as “circulating”: “Tornado Flush, as TOTO calls the whirlpool flush, essentially cleans every centimetre multiple times. The water swirls in a circle. This movement keeps the water inside the toilet. And this type of toilet or flush to a large extent ensures that intestinal pathogens actually stay in the toilet and do not spread further. As a result, this type of toilet is especially well-suited for use in hospitals,” Zastrow said.

The study also carefully examined whether or not droplets had settled on the cleaned and polished floor surrounding the toilet after it was flushed, as this would indicate the formation of aerosol particles. The hygiene specialist eliminated this possibility: “The aerosols that are produced by conventional toilets from time to time are not an issue for rimless toilets.” In an interview, Zastrow was asked whether or not coronaviruses would behave like the bacteria and germs he tested. He felt that there was no difference: “Everything that is in the stool, including viruses and bacteria, as well as coronaviruses, is also eliminated.”

Like all TOTO toilets, the tested RP and SP models offer outstanding hygiene features. The special CEFIONTECT glaze is easy to clean, extremely smooth and as hard as glass. It essentially prevents germs and waste from sticking to the surface. One of TOTO’s greatest innovations in conjunction with ceramic toilets is the development of the rimless toilet bowl, the first to bring this to Europe at the 2009 ISH trade show. The toilets also share the extremely efficient, circulating flush technology called Tornado Flush. 

“Considering the special issues surrounding MRGN*, the wall-mounted toilet from TOTO meets all of the demands involved in hospital hygiene and completely prevents infection. It is superior to conventional toilets with rimmed bowls and non-circulating flushes 

*Definition: MRGN stands for multi-resistant gram-negative rod-shaped bacteria, which are widely resistant to antibiotics.

The fact that this sophisticated technology was developed in Japan, a country known for its exceptional hygiene, is an advantage. The company is seeing increased demand in the European market during the pandemic for both toilets and shower toilets, known as WASHLET^TM. 

An abridged version of the interview is available for viewing on the TOTO YouTube channel:

https://www.youtube.com/watch?v=LHF5hGQdpLg

The expert report is available online at:

https://de.toto.com/fileadmin/Prof_Dr_Zastrow_2_Gutachten_TOTO_31_07_2020

Düsseldorf, August 2020
Reprint free of charge/copy requested

TOTO brings luxury to bathroom culture, creating innovations that deliver the ultimate in design, comfort and hygiene without revealing the sophisticated technology integrated within. Japan’s leading supplier of bathroom products, TOTO develops comprehensive solutions for high-end private and public spaces around the world, including the European market since 2009. The company is shaping bathroom design with innovative sanitary ware, faucets, and, most importantly, WASHLET – selling over 70 million worldwide. TOTO’s Japanese design philosophy reflects a respect for others. It centres on people and their needs, inspiring intuitive, easy-to-use products and elegantly understated designs. TOTO shows this same respect for the environment, developing water-saving technologies that help conserve resources while pursuing its sustainability strategy in internationally recognised initiatives like Climate Group RE100 and the Science Based Targets Initiative.