At cross purposes
Hot and cold water tap technologies are rapidly changing and one of the challenges for plumbing product manufacturers is to ensure the standards that support these products are being appropriately updated. Plumbing products industry group technical director Tim Fisher explains.
The following are some observations of current tap type technologies and anomalies as to their function, which is causing confusion in the market.
AS/NZS3500 requires that with tap sets, the hot tap is positioned on the left and that the cold tap is on the right side as you look directly at the ﬁxture. This has been the traditional way of plumbing three hole tap sets be they for the kitchen, wash basin, shower or bath. The introduction of single lever mixer technology saw this basic positioning and understanding retained with a movement through an arc controlling temperature while ﬂow was now controlled by lifting a lever.
However, with the development of numerous new ceramic disc headworks and touch-free electronic products delivering improved energy, hand hygiene and water eﬃciency outcomes, their modes of operation have also changed, which are vastly different from traditional three hole and basic single lever mixer technologies.
Further innovation has also been introduced with sequential headwork designs being incorporated into single lever, point-of-use, thermostatic mixer technology adding precise temperature control to the mix. In these designs the operation of the lever of the thermostatic mixer technology sees that cold water delivery begins with the lever in the left hand position and as water begins to ﬂ ow, the lever is moved through a radius towards the right where temperature controlled heated water is now delivered.
Safe enough? Yes, of course. Energy eﬃcient? Yes, of course. However, our installation and product codes remain signiﬁcantly behind such innovations providing signiﬁcant opportunity for Plumbing Products Industry Group to drive technical change, not only in this instance but across numerous product areas where innovation developed by members has left outdated standards in their wake.
This may also pose the question of liability. From a water temperature and scald protection perspective we are fortunate that code changes introduced in the late ‘90s have eﬀectively minimised these risks through the mandatory installation of temperature control products such as TMVs and tempering valves. However, it is understood that while new build and high risk installations have been addressed, signiﬁcant existing infrastructure across the country has been left unaddressed.
So, whose responsibility is it to ensure that users of a facility know how to operate taps that may have been speciﬁed and installed, especially if a scald risk remains in the installation?
As an example, discussions with various service companies have identiﬁed that some of the new technologies installed, especially in public accessible areas have resulted in increased maintenance where no signage exists or is desired, leaving the public attempting to operate products in a manner that they believe they should operate them, only to ﬁnish up causing damage most often through frustration.
Recent questions have again been raised as to whether ‘new’ products such as the wide variety of sequential thermostatic mixer technologies now available on the market actually comply with the provisions of AS/NZS3500 as discussed earlier? In this instance, the response has been that the hot/cold positions stated are speciﬁcally for a tap. Thermostatic mixer technologies are currently not able to be classiﬁed as taps, given that AS/NZS3718 Water Supply – Tapware is speciﬁcally for nonthermostatic taps.
Current certiﬁcations for the thermostatic mixer technology are based on AS4032.1 Thermostatic Mixing Valves, while AS4032.4 Thermostatically Controlled Taps are in the process of being accepted into the WaterMark Scheme. However, once this adoption has been veriﬁed do we ﬁnish up with conﬂict?
Then, what about WELS ratings? Finally, shall the impending introduction of touch-free, sensor-operated thermostatic mixer tapware also pose challenges to the installation codes currently in place? Intuitive functions with visual indicators of some proposed technologies are anticipated to see the user increasing temperature of the water through a left to right movement and decreasing temperature through right to left movements of the hand, all of which are opposite to the traditional hot on the left cold on the right functionality.
What this does, though, is provide PPI Group the opportunity to identify and address the need for alignment between product and installation code change proposals and future development. And in this litigious world we live in, unless these issues are addressed, we leave the industry open to attack in a legal form.