Energy/utility savings are becoming more prevalent in building managers’ roles in reducing their facility’s operational costs. Water consumption savings are attractive with the latest in low-flow plumbing fixtures, and the consumption savings trickle into reduced water heating capacity too. Although it may seem like a simple task in specifying low-flow fixtures or even replacing plumbing fixtures in renovation work, there are some risks associated with doing so, especially with shower heads. Low-flow shower flow rates can be as low as 1.0 to 1.5 gallons per minute (gpm) which can provide significant water savings over the standard 2.5 gpm shower heads and even more savings from older heads ranging from 5 to 10 gpm.
One potential risk at the lower flow rate is scalding. American Society of Safety Engineers (ASSE) standard 1016 was developed to provide scalding protection to the bather for individual shower or tub/shower combination valves. The standard applies to three valve types: Pressure Balancing (Type P), Thermostatic (Type T) and Combination Thermostatic and Pressure Balancing (Type T/P).
It may be possible in existing facilities that the control valve is not one listed above and does not provide scalding prevention. In this circumstance, it may be beneficial to replace the control valve as well as the shower head. Even if there is an existing control valve listed above, it may not provide the intended scald protection if the minimum flow rate is greater than the shower head flow rate. Also, in facilities with master mixing valves (for the entire plumbing system) it is still important to perform due diligence in checking if there are any valves listed above and whether there is the potential for failure or bypass of the master valve that could contribute to a scalding condition. Overall, it is important to remember when either retrofitting existing shower heads or piecing together a tub/shower fixture package to check the control valve to ensure that a low-flow shower head is in compliance with the manufacturer’s tested data.
If you have any questions or have a project with which we can assist you, please do not hesitate to contact Jarod F. Stanton, PE, LEED AP at (814) 237-2180 or jfs@ba-inc.com.