Grant, Walter G., F.S.A.ScoT.; Childe, V. G., F.S.A.ScoT. (1938). "A Stone-Age Settlement at the Braes of Rinyo, Rousay, Orkney. (First Report.)". Proceedings of the Society of Antiquaries of Scotland. 72 . Retrieved 6 May 2020. {{ cite journal}}: CS1 maint: multiple names: authors list ( link)

Wald, Chelsea (26 May 2016). "The secret history of ancient toilets". Nature News. 533 (7604): 456–458. Bibcode: 2016Natur.533..456W. doi: 10.1038/533456a. PMID 27225101. S2CID 4398699. Kagan, Mya. "Where Does the Water Go When I Flush the Toilet?" Kids' Why Questions. Whyzz. Publications LLC, 2011. and below: We don't recommend potty chairs with this rating; you won't find any on our list. We Also TestedIn North America, newer toilets have a 3in (76mm) flapper-flush valve. Older toilets have a 2in (51mm) flapper-flush valve. [9] The larger flapper-flush valve is used on toilets that use less water, such as 6.1L (1.6USgal) per flush. Some have a bell inlet for a faster more effective flush. Made by Blue Diamond, it’s unique in our guide as it doesn’t require water or chemicals to operate. Instead, it is advised that a biodegradable liner is used in the solids container, as well as applying a sprinkling of wood shavings, sawdust or similar after each use. This not only helps to start the composting process, but should also prevent any strong odours. Examples of this type of toilet can be found in Austria, the Czech Republic, Germany, Hungary, the Netherlands, and some regions of Poland, although it is becoming less common. Our editors and their kiddos tested 22 potty chairs and seats in the comfort of their home, assessing each on several attributes, such as stability, ease of cleaning, design, and overall value. We also consulted with Arthur Lavin, MD, FAAP, a pediatrician at Akron Children's Hospital in Ohio, for guidance on toilet training for both kiddos and parents/caregivers.

Best, E.L.; Sandoe, J.a.T.; Wilcox, M.H. (1 January 2012). "Potential for aerosolization of Clostridium difficile after flushing toilets: the role of toilet lids in reducing environmental contamination risk". The Journal of Hospital Infection. 80 (1): 1–5. doi: 10.1016/j.jhin.2011.08.010. ISSN 1532-2939. PMID 22137761. Another pioneering manufacturer was Thomas William Twyford, who invented the single piece, ceramic flush toilet. [59] The 1870s proved to be a defining period for the sanitary industry and the water closet; the debate between the simple water closet trap basin made entirely of earthenware and the very elaborate, complicated and expensive mechanical water closet would fall under public scrutiny and expert opinion. [59] In 1875 the "wash-out" trap water closet was first sold, and was found as the public's preference for basin type water closets. By 1879 Twyford had devised his own type of the "wash out" trap water closet; he titled it the "National", and it became the most popular wash-out water closet. [59] Flush toilets were widely available from the mid to late 19th century. Although Thomas Crapper did not invent the flush toilet, he was a leading manufacturer.The performance of a flush-toilet may be rated by a Maximum Performance (MaP) score. The low end of MaP scores is 250 (250grams of simulated fecal matter). The high end of MaP scores is 1000. A toilet with a MaP score of 1000 should provide trouble-free service. It should remove all waste with a single flush; it should not plug; it should not harbor any odor; it should be easy to keep clean. The United States Environmental Protection Agency uses a MaP score of 350 as the minimum performance threshold for HETs. [26] 1.6 gpf toilets are also sometimes referred as Ultra Low Flow (ULF). a b Tilley, Elizabeth; Ulrich, Lukas; Lüthi, Christoph; Reymond, Philippe; Zurbrügg, Chris (2014). Compendium of Sanitation Systems and Technologies (2nded.). Duebendorf, Switzerland: Swiss Federal Institute of Aquatic Science and Technology (Eawag). ISBN 978-3-906484-57-0. Suddath, Claire (19 November 2009). "A Brief History of Toilets". Time. Time . Retrieved 6 May 2020.