IH02-ShwanKazzaz

From IEOR 170 Spring 2007

Building a Better Toilet

The Context:

Unfortunately, public restrooms in the United States have never quite been heralded as the hallmark of cleanliness or sanitation. Men’s and women’s restrooms are commonly cluttered with dirty toilet paper, the floors are often soaked in urine, and the common surfaces (handles, knobs, etc.) are rarely considered clean. However, the typical public restroom also suffers from terrible design, and therein do we find hope for a cleaner, more sanitary, public restroom that no one is too shy to use. By focusing mainly on the design of the common toilet, it is hoped that good design can persuade the user to be less careless, in turn improving the public restroom experience for everyone.

A Common Toilet:

Figure 1

The Problem:

The common toilet comes in two main construction types. The customary toilet illustrated in Figure 1, and the urinal. We will focus on the construction of the customary toilet.

The main problems of the customary toilet include:

• Splashing
  • While standing (a.k.a. “splash-back”)
  • While sitting
  • While flushing
• Clogging
• Sanitation
  • Flush handle
  • Seat
  • Inside of the bowl
• Cold seat

Some of these problems have already been tackled, mainly by Japanese toilet manufacturing giant, Toto. The features of some of the more high-tech toilets include: seat warmers, built-in bidets (with air-dryers), air deodorizers, sound effects to mask your own, and even a chemical urine analyzer. Accordingly, this project will not attempt to solve problems already being addressed by the higher-end Japanese toilets. However, it will focus on tackling the unaddressed issues of splashing and clogging, while still attempting to address the issues of sanitation and comfort without creating a product that will cost over $750.

The Forces:

The typical user of a public restroom can be anywhere, in schools, movie theaters, bars, office buildings -- the list goes on. But one common thread between all users is that they would like to get in, use the toilet, and get out.

Because many toilets splash back up onto their users, whether sitting or standing, this is a primary problem. With male users, when urinating, it is common to stand back from the toilet to avoid this splash-back. However, this creates a new problem, and is cause for most of the urine on the ground in men’s restrooms (aside from that caused by splash-back). Standing back worsens aim, and encourages urination directly onto the floor. Thus splash-back will be one of the primary design concerns for this project.

Additionally splash-back to any user who is seated, if the feces or urine strikes the pool of standing liquid in the toilet, it is likely it will cause it to splash onto the user.

Often users lay down toilet paper before defecating to break the impact at the water’s surface and to prevent splashing. However, this can create a natural “perfect clog,” as the combination will jam in the toilet when flushed.

The Target Users:

Anyone in a public place who needs to use the restroom.

The Solution Sketch:

Figure 2

The bowl shape has been redesigned, and more water jets have been added. The idea is that feces and female urine (sitting down) will hit the shallow front of the bowl, and get washed down the bowl by the jets. Male users can aim the urine stream at the water, but because there is so little of it, there is less splash-back and male users can stand closer without worrying about splashing. The surface is also made of a non-stick surface whose composition will be further researched.