The following is a Google translation of an article originally found on German website http://www.sbz-online.de/ about the testing of 32 rimless toilets that have recently been introduced on the German market. We published a version of the story in issue 2-15 of Plumbing Connection magazine; however we thought some readers may be interested in the whole story direct from the testers. Some parts are fairly rough, in terms of translation but you will get the general gist of the testing procedures and subsequent results. It will be interesting to see whether Australia adopts a similar technology in the future.

Surprising results under scientific management were reviewed on a newly developed specially constructed for the test series of 32 rimless toilet models on functional and hygienic properties. The Hochschule Esslingen (HSE) and the SBZ editors have jointly developed a testing program. This was designed independent of corporate interests and funded by the university and the Soviet occupation zone.

Rimless toilets have only been available on the German market in recent years. The importance of these toilets comes to the fore when it comes to the issues of cleaning and hygiene. There still remain some uncertainties about the practicality of rimless toilets though.

The DIN EN 997 is a technical code used to verify certain functional requirements. However, this set of rules was originally designed for toilets with flushing rims. While it has been adjusted retrospectively on rimless toilets, the inspection regarding rinsing performance and cleanability in DIN EN 997 are not sufficiently defined for water-rimless toilet bowl.

As SBZ-editor in chief Dirk Schlattmann Dr. Hans Messer Schmid of the project, a neutral, vendor-neutral test build number for toilets, informed the professor supporting the Esslinger University told spontaneously. As a result, the study plan were “SPWC 12/15” and the so-called “Esslinger dishwashing test” developed. After a concept for the 13 test stations comprehensive test bed was developed, built laboratory master Achim racing and Yilmaz Alkan a booth with the latest measuring and documentation technology. Was built a double-row bench with twelve toilet seats. Was docked a standard test rig, on the follow-up also water quantity and other normative detailed tests were conducted.

The SBZ practice test is a combination of parts of Normspülversuchs accordance with DIN EN 997 and a Central European accordance with the requirements user habits specially developed practical part. Were tested all 32 models the manufacturer Duravit, Ideal Standard, Keramag, Laufen, Roca, Toto, Villeroy & Boch and Vitra, which were to relate October 2014 on the German market via wholesalers. The companies have purposely placed two copies available.

Flow of cisterns important criterion

Since water conservation in Central Europe makes no sense for different reasons, the tests were carried out with a flush water of 6 l. Input has been experimenting with different volume flows of commercial cisterns up to a maximum flow rate of 2.8 l. It came with all rimless toilets to violent overmolding. Ultimately reactors were built in the TECE cisterns that still had a flushing flow of 2.05 l / s within the framework of permissible standard tolerances in accordance with DIN EN 997. The test for the trailing/flushing water was calibrate to exactly 2,1 l / s. Also crucial for the overmolding is the so-called impact force, which is released during flushing. Since rimless toilets are very sensitive to these parameters, the installer will currently only test the toilet system after installation and install commercially available restrictor pieces in the cisterns during overmolding. Manufacturer Tece has already responded to the product category of rimless toilets a product optimization. And at the ISH 2015 come throttle sets on the market that allow the installer to adjust the purge flow respectively desired.

How we tested

With DIN EN 997, there is a standard for testing requirements for WC pans and WC suites with an integral trap. Part of the Esslinger experiment was conducted as a basic requirement in accordance with this standard. In addition, further, practically relevant tests have been developed and carried out. According to the results obtained by the HSE, bowl points were awarded. To determine the overall scores, marks from 1 to 6 and a certificate for each product were awarded.

In accordance with DIN EN 997 tests carried out

Surface irrigation with sawdust: To test the final rinse and document the test was carried out with 20 g of dry, fine-grained wood sawdust. This was sprinkled evenly on the previously moistened Beck inside. When tested in the area of ​​flushing toilet bowl without flushing rim, the arithmetic mean of five tests the non-rinsed surface was determined in the range between the water surface in the trap and a horizontal line 85 mm below the top of the pelvic cavity. This area must not exceed 50 cm ^2. If the area between the water surface in the trap and a horizontal line 85 mm below the top of the basin mold completely rinsed, 100 points were awarded. For non-flushed faces a point per cm ² will be deducted. Only five toilets flushed as part of the requirements is not completely out and managed the maximum score of 100 not (Table 1).

Flushing of toilet paper: 12 sheets each Norm orientated toilet paper were crumpled individually loosely inserted in succession in the toilet bowl within 14 to 18 seconds. Two seconds after inserting the last sheet of the flushing has been triggered, and all non-flushed toilet paper sheets recorded. This test was carried out five times. In each 12 sheets of toilet paper at least four out of five trials had to be flushed out of the toilet bowl. Toilet bowl, in which all five attempts all paper sheets were rinsed, received 100 points, with only four of five attempts all paper rinsed 50 points, with only three out of five trials (two failed attempts) 0 points. Except for DuraStyle, 4U / Icon, Xeno and ² per rimless compact all products received a perfect score. The table can be found on the test report http://www.sbz-online.de/extras.

Rinsing of 50 plastic balls: In this test, the simulated inter alia rinsing of cigarette butts, must with 50 plastic bullets at least 85% of the balls are rinsed out of the toilet bowl during the five tests. The points were distributed as follows: In all five experiments all paper rinsed 100 points. In four out of five attempts all paper rinsed (a miss) 50 points. In only three out of five trials (two failures), there was no point. The range of results in these experiments ranged from 41 to 100 points.

Splash over the edge of the pool addition: There shall be no rinse water out of the tub and wet the floor. Only a few small drops are allowed. Around the toilet bowl to be tested was placed a paperboard covered with a supernatant of 200 mm on the basin on the floor. The toilet bowl was flushed and leaked over sprayed water on the box has been logged. In this experiment, the water splashes were counted that were visible after flushing on the cardboard box. Were visible no water splashes, 100 points were awarded. The water splashes less than 2 mm, a point was deducted, depending splashes greater than 2 mm, two points were deducted. The range of results was 68-100 points.

Trailing water test according to DIN EN 997: For the cleaning ability of the toilet bowl following sewers is important that the trailing amount of water is as great as possible. Four standard test specimens were placed in this test successively in the toilet bowl, then rinsed. The trailing volume of water, which expires after the last specimen has left the basin drain was measured. This test is carried out ten times. Assuming that, with a flushing volume of 6 l of at least about 1 l for rinsing of the test specimens is required, a maximum of 5 litres would be achievable as a tracking volume of water. Would thus reached 5 litres on average of all ten attempts for 100 points would be awarded. This consideration has so far confirmed in the tests carried out, as no manufacturer has reached more than 4.7 litres trailing amount of water in the standard tests. The limit in accordance with DIN EN 997 is 2.8 litres for the average of the ten tests or at least 2.5 litres per test, if a maximum of two trials not all specimens are rinsed. If this normative limit is reached during the tests, but 50 points will be awarded. The range of results achieved in these experiments was between 50 and 100 points.

Practice-relevant additional examinations

The inspection specifications regarding rinsing performance and cleaning facilities are not adequately defined in the DIN EN 997 for water rimless toilet bowl. So toilet bowl some manufacturers have a small, directed towards the inner basin side skirt, while other toilet bowl does not have this apron. Likewise, the size of the water surface in the siphon is a different size. Due to the structural peculiarities of the toilet bowl, there are differences in surface irrigation and the rinsing behaviour. Therefore, the SBZ-Praxisspültest the standard tests have been extended by additional tests and the relevant product-specific advantages and disadvantages identified.

While there may be contamination of the basin inside from spills of urine in the front half of the toilet bowl, rather Fäkalanhaftungen are the reason for the contamination at the rear of the pelvis. To take account of these circumstances, the toilet bowl was divided by marks in a front and a rear half. In the front half of the entire non-flushed flushing rim was measured (Spülrandtest). In the back of the pelvis the non rinsed surface was below the Spülwassereintrittsöffnungen measured (smear).

Spülrandtest with blue food: To document the elimination of pollution of the basin inside from spills of urine, this test has been developed for the SBZ Practice Spültest. The inner surface of the toilet bowl was wet uniformly with a sprayer with blue food coloring. In this case was also the lower edge of the inwardly curved apron, if present, is sprayed. The measurement of non-rinsed surface was carried out using printed on film 0.5-cm squares. In contrast to the standard the whole, not bespülte area in the front toilet pelvis below the pool edge was detected and thus possibly also the inwardly curved apron. If the entire surface flushed clean, there are 100 points. Remained this area entirely without flushes, there were no points. Per square centimetre without washed up space therefore points were deducted. The range of results achieved was 39-79 points (Table 6).

Smear with ketchup: In the back of the pelvis adhering feces are the friend of each toilet brush. Therefore clean rinsing is especially important here. When lubricating test that simulates the Fäkalanhaftungen, the rear half of the inside below the Spülwasseraustrittsöffnungen was daubs evenly with ketchup. Immediately after application of the pad was rinsed. Was determined the area that was still visibly soiled after a full flush. 100 points were awarded when the entire area was rinsed clean under the water inlet openings (in the back half of the toilet bowl) without residues. For every square centimeter without flushed face, a point was deducted. The range of results presented 43-100 points (Table 7).

Apron width for cleaning Important: The ease of cleaning of the toilet bowl is an important quality. Due to the preferred by some manufacturers more or less wide skirt the toilet bowl is not fully visible. Contaminants below the apron can only poorly or not be recognized. Therefore, the width of this apron was measured. Between 40 and 100 points were then, as detailed in Table 8, forgive.

Lowest non washed up point: In connection with the cleaning of the toilet bowl is not only the non-flushed pelvic area, but also the deepest point of interest without rinsing. Because when rinsing can below the water inlet openings striated adhesions remain, although in terms of area have little impact, however, adversely affect the hygiene and the visual impression of the user. The points were awarded to the following scheme:

Lowest non washed up point 0 mm below top edge pool = 100 points; 85 mm below OK pool = 0 points. The range of results was 1 to 82 points (Table 9).

Water surface in siphon: With regard to the cleaning of the toilet bowl the size of the water surface in Beckensiphon for contamination by adherent faeces is important. The greater this is, the smaller the area, drop in the solids directly on the ceramic and adhere. Therefore, this measure appears in the presentation of the results under the heading “water surface”. The maximum value is 143 cm² . For this value of 100 points will be awarded. For every square centimetr less 100/143 points are deducted. The range presented on 49-100 points, as in the test report http://www.sbz-online.de can be read under Tools.

Ausspültest with dumplings and paper: Since it is impractical to flush paper and specimens separately, a further practice-oriented test was conducted. Following the US-Standard Ausspülversuche were conducted using specific specimens and paper. This five specimens were introduced stencilled in the toilet bowl. Then 16 were three-ply sheet, divided commercial paper into four portions à four leaves and also folded into the basin given. Two seconds after inserting the last leaves were triggered flushing. The experiments were repeated five times. The non-purged test specimens as well as the number of paper sheets were not rinsed logged. Were purged all specimens and all paper in the middle of all five attempts, so 100 points were awarded. For each test specimen not flushed ten points for each not flushed paper (four sheets) were deducted five points. The range of results was between 90 and 100 points.

Practice-oriented follow-up water flow test. According to recent surveys Europeans have usually daily bowel weights of 100 to 200g, vegetarians due to the higher fiber content in the diet up to 350 g The amount of excreted at a single fecal material may also be up to 1 kg in the individual case , For the cleaning of the toilet bowl following sewers, it is important that the follow-up amount of water is as large as possible and the feces and paper residues are transported.

In order to achieve a realistic trailing amount of water in accordance with DIN EN 997, this experiment was carried out with the specimens according to US standard. These seven specimens (350 g) were successively added by the template in the toilet bowl. After that was rinsed with 6 liters flush water and measured the water, which expires after the last specimen has left the basin drain. This test was repeated five times. Could all seven test specimens are rinsed, this yielded 100 points. No specimens did not point. In between was interpolated. It was noticeable that some toilet bowl could not rinse or a few specimens. All seven specimens remain after rinsing in the siphon, the overrun amount of water was set at 0 l. The range of results obtained in these tests: 12 to 100 points.

No toilet everywhere top

The evaluation of the 12 individual tests were carried out according to a 100-point key. Since the tests carried out a clear focus on the practical relevance, the tests specified in DIN EN 997 provided only 50% in the overall evaluation. A total of 950 points were reached. For the grade 4.4 at least 475 points were required. It was noticeable that no WC has top cut off in all disciplines. Therefore worth a detailed look at the individual test areas. In addition to the information collected here is the original report on http://www.sbz-online.de deposited under Extras. Which took place partly in the fall of 2014, optimizing product range has preserved some manufacturers of bad results. With a grade of 1.9, the SG-WC of Toto and Darling New Duravit winner.

Overall, the result for this type of product is gratifying. Occupies the SBZ-Praxisspültest but that rimless toilets are a type of product that meet the growing demands on hygiene and cleanability bill and that the products are marketable. Provided that the cisterns are not too high with their flow.