4 FM quick reads on Urinals
1. How do waterless urinals work?
Typically, the bodies of waterless urinals are constructed of vitreous china or porcelain, similar to standard flush urinals. Most waterless units use a liquid sealer and rely on a density differential between the sealant and the liquid waste. The sealant is less dense than water or urine, which pass through the sealant. The sealant creates a barrier between the liquid waste and the urinal bowl.
Liquid-seal urinals feature two different designs: cartridge and integrated drain trap.
The cartridge design uses various types of disposable cartridge inserts that fit into the custom-designed urinal base. The cartridge might simply slide into the base, or it might require a special tool for insertion and removal.
The cartridge typically contains a half-liter of water and is topped with a liquid sealant. This cartridge collects sediment and directs the flow of liquid waste to the drain while blocking odors.
The integrated-trap design does not use a cartridge. Instead, it uses a liquid sealant that separates the waste from the urinal bowl through a fixed basin trap or a trap built into the urinal body.
Yet another type of waterless urinal does not require a liquid seal to operate. This urinal uses a flexible silicone diaphragm or elastomeric, expanding check valve. Typically housed in a removable cartridge, the diaphragm or check valve allows liquid waste to pass through and then seals, preventing sewer gases from entering the restroom.
Selecting Water Closets and Urinals
In many organizations, there are two priorities for restroom fixtures: cleanliness and sustainability. In some cases, those two goals can be in conflict. But that need not be the case. Understanding fixture options is key to the balancing act.
First, determine the sustainable approach for the organization. Some owners only want code-minimum facilities; others want a moderate sustainable goal of LEED certification. Others take an aggressive approach and want as many water-efficient fixtures as possible in their facilities.
Next, ask the same questions about cleanliness issues. Health care facilities have deep concerns about infection control and keeping patients and the public from touching plumbing fixtures. As a result, they will have an aggressive approach. In other types of facilities, where employees rather than the public will be using the fixtures, a moderate approach may be taken.
Let's take a look at how different plumbing fixtures can help facility managers plan for restroom facilities that perform the balancing act between maintainability and sustainability.
A good place to start is with water closet considerations. With new construction, major renovation projects and replacement fixtures, facility managers should remove old fixtures using more than 1.6 gallons per flush (gpf) and replace them with newer, more efficient fixtures that use 1.28 gpf.
One tool to help in selecting fixtures is the EPA-sponsored WaterSense program. WaterSense-labeled fixtures are third-party tested, ensuring compliance with both the required effective flush volume and solid waste removal. When possible, specify fixtures that have the WaterSense label.