DoE PROJECT 10B WATER ECONOMY 11727/2
Report No DWI0709/2
This report compares the performance tests required of WCs and flushing devices in various countries around the world. Installation and maintenance requirements, including qualifications of personnel, are also reviewed.
An overview of attitudes to water conservation and regulatory systems applicable to plumbing installations is provided.
Eleven countries were considered in the survey, extending to North America, Japan and Australasia and including six leading countries in the European Union.
General attitudes to water conservation vary between countries but awareness of water use is likely to be influenced by measurement of individual supplies. In all the countries surveyed water meters were either universally used or installed in the vast majority of residential buildings. This compares with a water meter penetration of just over 5% amongst households in the UK. It can be argued that charging for a measured supply of water gives greater encouragement for householders to rectify leaks or install water conserving equipment.
The structure of regulations affecting plumbing installations varies between countries, but in most countries requirements are ultimately set and enforced at local level, based on national model regulations and standards. In Germany and the Netherlands as well as most parts of the USA, Canada and Australia standards and codes of practice are regulatory documents, enforced by regional or local government or water undertakings.
In most countries WCs and flushing devices are required to meet relevant standards or other criteria. In Germany, the Netherlands, Canada and Australia an approval mark issued by a particular certifying body is required.
Installation requirements for WCs are set out in regulations or in "deemed to satisfy" guidance. In most countries the installation must be carried out by a qualified and registered plumber.
Specific requirements for regular maintenance of WC systems and their components were only found in a few countries. In general, enforcement of any requirements, particularly amongst privately owned single family dwellings, is likely to be limited to response to defects affecting neighbours or the supply main.
Table 1 gives an overview of the test requirements for WC pans in eight of the countries surveyed with requirements of the current British Standards and the draft European Standard included for comparison purposes.
|Pan Surface Washing|
|After Flush Volume(1)||Y||Y(2)||Y||Y(6)|
|Retention of trap seal||Y||Y||Y||Y|
The most comprehensive set of tests for flushing efficiency are those contained in the American National Standard ANSI/ASME A112.19.6 (1990).
Table 2 presents an overview of test requirements in various countries for flushing cisterns, cistern components and other flushing devices.
|Force of water jet||-||-||Y||Y|
Note 1. Test for variation in water level.Copies of this report may be available as an Acrobat pdf download under the 'Pre 2000 Reports' heading on the DWI website.