Over flushing
Over flushing is common in most urinals, in some cases as much as 4.5 Litres of water are being flushed down a single urinal every 5 minutes, this equates to 1,296 Litres of water every day and close to half a million Litres per year.

Over flushing causes an accelerated build up of lime scale. As lime scale is very porous it quickly absorbs uric salts, and bacteria's found in urine, causing those common horrific urinal odours.

In addition water supply (water fittings) regulations 1999 schedule 2, section 9, paragraph 25 (4a2) limits water usage to 7.5 litres per urinal per hour.

Blockages
The build up of lime scale, uric salts, sludge, chewing gum and cigarette butts will quickly restrict the water flow-rate running through the urinal system, causing blockages. The urinal bowls will often block-up, over flow and flood the washroom.

Chemical blocks
The above problems are normally tackled by the introduction of chemical blocks along with more frequent flushing. In the 1980's bi-laws were introduced to reduce water flushing to a maximum of 4 flushes per hour. Many organisations are not aware of this law and have not introduced water management systems, therefore urinals are flushing on an almost continuous cycle, which in turn equates to even more lime scale build-up. Chemical blocks sit at the base of the urinal for substantial periods of time until they dissolve. However because they sit in a continuous pool of water/urine they soften and brake up into small particles falling down into the trap below. This can cause further problems, as they will quickly develop a foam exterior known as 'Bio-mass'. Biomass builds up very quickly and this too will block up a urinal system.