Editing Urinal (section)

==Urinals with flushing==
Most public urinals incorporate a water flushing system to rinse urine from the bowl of the device, to prevent foul odors. The flush can be triggered by one of several methods:

===Manual handles===
[[File:Urinal - New Orleans 2020.jpg|thumb|Urinal flushing handle]]
This type of flush might be regarded as the standard type of flush in [[North America]]. Each urinal is equipped with a short lever to activate the flush, with users expected to pull it down as they leave. Such a directly controlled system is the most efficient, provided that patrons remember to use it. This is far from certain, however, often because of fear of touching the handle, which is located too high to kick.<ref>With public sit-down toilets, users often kick the flush lever to avoid the perceived or real possibility of infection from touching it.</ref> Urinals with foot-activated flushing systems are sometimes found in high-traffic areas; these systems have a button set into the floor or a pedal on the wall at ankle height. The [[Americans with Disabilities Act]] requires that flush valves be mounted no higher than {{convert|44|in|cm}} AFF (above the finished floor). Additionally, the urinal is to be mounted no higher than {{convert|17|in|cm}} AFF, and to have a rim that is tapered and elongated and protrudes at least {{convert|14|in|cm}} from the wall. This enables users in wheelchairs to straddle the lip of the urinal and urinate without having to "arc" the flow of urine upwards.

===Timed flush===
[[File:22.Naivasha- Urinal Cistern (4426405151).jpg|thumb|Urinal cistern]]
In [[Europe]] and [[South America]], manual flush handles are unusual. Instead, the traditional system is a timed flush that operates automatically at regular intervals. A group of urinals will be connected to a single overhead cistern, which contains the timing mechanism. A constant drip-feed of water slowly fills the cistern until a tipping point is reached, when the valve opens (or a [[siphon]] begins to drain the cistern), and all the urinals in the group are flushed. Electronic controllers performing the same function are also used.

This system does not require any action from its users, but it is wasteful of water when toilets are used irregularly. However, in these countries users are so used to the automatic system, that attempts to install manual flushes to save water are generally unsuccessful. Users ignore them not through deliberate laziness or fear of infection, but because activating the flush is not habitual.

To help reduce water usage when the urinals are not being used, some urinals with timed flushing use a water-saving device. The cistern will be connected with a [[passive infrared sensor]], which makes the cistern stop filling unless the urinals are being used. The sensor can be wall or ceiling-mounted, and will detect movement within the range of the urinals.

===Door-regulated flush===
Used mostly in the countries of [[Asia]]. This is an older method of water-saving automatic flushing, which only operates when the public toilet has been used. A [[push-button]] switch is mounted in the door frame, and triggers the flush valve for all urinals every time the door is opened. While it cannot detect the use of individual urinals, it provides reasonable flushing action without wasting excessive amounts of water when the urinals are not being used. This method requires a spring-operated automatic [[door closer]], since the flush mechanism only operates when the door opens.

Alternatively, a flushing system connected to the door can count the number of users, and operate when the number of door opening events reaches a certain value. At night, the door never opens, so flushing never occurs.

===Automatic flush===
[[File:Zurn OmniFlo urinal at Sheetz in Bedford PA.jpg|thumb|Urinal with automatic flush valve]]
[[File:Surveilluminescent Lights in Motion handwash faucets 02.jpg|thumb|Long-exposure photography shows the sensors' detecting range]]
Automatic flush valves solve the problems of previous approaches, and are common in new installations all around the world. A passive infrared sensor identifies when the urinal has been used, by detecting when someone has stood in front of it and moved away, and then activates the flush. There usually is also a small override button, to allow optional manual flushing when the sensor is not working.

Automatic flush facilities can be retrofitted to existing systems. The handle-operated valves of a manual system can be replaced with a suitably designed self-contained electronic valve, often battery-powered to avoid the need to add cables. Older timed-flush installations may add a device that regulates the water flow to the cistern according to the overall activity detected in the room. This does not provide true per-fixture automatic flushing, but is simple and cheap to add because only one device is required for the whole system.

To prevent false-triggering of the automatic flush, most infrared detectors require that a presence be detected for at least ten seconds, such as when a person is standing in front of it. This prevents a whole line of automatic flush units from triggering in succession if someone just walks past them. The automatic flush mechanism also typically waits for the presence to go out of sensor range before flushing. This reduces water usage, compared to a sensor that would trigger a continuous flushing action the whole time that a presence is detected.