Therefore through prescriptive application of significant low flow rates, laminar flow outlet technology that is considered standard for these clinical applications is unavailable.

Further we must also then look at the heated water source that shall supply warm water to these fixtures within healthcare facilities. Enware’s Aquablend range of thermostatic mixing valves (TMVs) is considered to be the leading brand in healthcare within Australia.

TMVs are the preferred source for delivering controlled temperature heated water in healthcare facilities and in NSW may only be substituted where a cost advantage can be demonstrated after consideration of capital cost and maintenance routine costs are taken into account according to NSW Health’s Engineering Services and Sustainable Development Guidelines. TMVs as mechanical devices have a minimum flow rate of 4 l/min at which they must comply with AS4032.1 – 2005. This value then becomes the benchmark for minimum flow rate settings at fixture outlets where stable temperature warm water is required to be delivered.

What is highlighted here is that guidelines from State Health departments, plumbing codes and environmental design parameters from within Green Building, which whilst all recognising the need for greater levels of water efficiency, cannot be viewed in isolation as these technology combinations, together deliver warm water for clinical hand washing applications and require a level of compatibility.

According to Tim, greater levels of water efficiency can be significantly influenced by technology such as electronic or self closing tapware that also controls the time a fixture runs without the need for manual intervention to shut off the supply which has a significant impact on water usage other than simply reducing flow rates.

“Looking at flow rate alone does not have an impact on the duration a person uses a manually operated fixture outlet, therefore we need a combination of flow rate, we need time control and when implemented according to the application need and actual number of usages at those facilities or fixtures within a day will provide far greater efficiency gains.”

When these factors are considered it becomes obvious that amending flow rates alone may not have the desired impact in seeking water efficiency gains and that a comprehensive overhaul and greater level of understanding of the interplay of the technologies and clinical handwashing requirements is needed. As designers and builders look to obtain a ‘green-star’ building ratings in healthcare establishments, simply ignoring vital cross infection control considerations of the intended facility cannot occur without increasing risk.

With these problems facing manufacturers and designers, their concern over possible mandated minimum flow rates without due consideration of all factors is understandable.