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Voluntary Water Efficiency Labelling Scheme on Urinal Equipment

WELS on urinal equipment is a voluntary scheme and adopts a grading type labelling system.

The urinal equipment applying for registration under the scheme will be tested to confirm its compliance with the performance requirements specified in the scheme which also include the dye test and physical endurance and leakage test for urinal flushing valves. In addition, the urinal equipment will be produced/manufactured according to a recognised international quality system (such as ISO 9001 or equivalent).

Under this Scheme, participating urinal equipment are classified into 2 categories in accordance with Table 1:

Table 1: Classification of Urinal Equipment

Category Description
1 Urinal Equipment in normal pressure application
2 Urinal Equipment in low pressure application

Note: In each category, it also includes urinal equipment operating with similar working principle.

The water efficiencies of the urinals with traps are rated to different grades according to their minimum water flush volumes per cycle required to fulfill performance while the water efficiencies of the urinal flushing valves are rated to different grades according to their total water flush volumes per cycle as shown in Table 2. Grade 1 is the most water efficient whereas grade 4 is the least water efficient.

Table 2: Conversion of Water Flush Volume per Cycle to Water Efficiency Grades for Urinal Equipment under normal or low pressure application.

Water flush volume per cycle
ƒ (litres/cycle)
Water Efficiency Grade Symbolic Presentation on the Water Efficiency Label 
ƒ ≤ 1.5 Grade 1 1 water droplet  water droplet.
1.5 < ƒ ≤ 2.5 Grade 2 2 water droplets water droplet. water droplet.
2.5 < ƒ ≤ 4.5 Grade 3 3 water droplets water droplet. water droplet. water droplet.
4.5 < ƒ Grade 4  4 water droplets water droplet. water droplet. water droplet. water droplet.

In order to sustain the performance requirements, a urinal and a urinal flushing valve registered under WELS on urinal equipment can be connected to form a combination provided that

  1. The water efficiency grading of the urinal and the urinal flushing valve must be the same; and
  2. The total water flush volume per cycle of the urinal flushing valve should not be less than the minimum water flush volume per cycle of the urinal.

Additional merit is given to the urinal equipment operated with a smart demand operation to achieve additional water saving. The merit(s) is/are shown on the Label and the registration certificate for public information.

The testing methodology is described in Annex 1 of the Scheme Document with reference to testing conditions and requirements specified in the American Standard No. ASME A112.19.2:2018 - Ceramic Plumbing Fixtures, Appendix D of Australian/New Zealand Standard No. AS/NZS 3982:1996 - Urinals and requirements in relevant Waterworks Regulations or other equivalent international standards approved by Water Supplies Department.  

Commencement of Registration to the Scheme

Registration to the scheme commences on 29 March 2012. No application fee will be charged. 

Further Information

WELS on urinal equipment is detailed in its scheme document.

Any enquiry on the Scheme can be referred to the Water Supplies Department Enquiry Hotline or by fax or by e-mail.

Sample Labels

Sample Label (full version).   Sample Label (simplified version).
Sample Label (full version)   Sample Label (simplified version)