Flow meters
The ability to accurately and effectively measure water flow is critical to the disinfection, filtration, and maintenance of safe water circulation rates. This responsibility rests with the flow meter, which must operate efficiently to maintain flow rates within safe limits to help prevent entrapment from pool/spa drains.
In 2012, NSF developed criteria and certified the first flow meter for pool, spa, and waterpark applications. Fluidics Hawaii, LLC’s FV-C mechanical flow meter was the first to earn NSF certification to the new standard, which has been submitted for inclusion in NSF/ANSI Standard 50.
The requirements include evaluation to verify material safety, corrosion resistance, burst pressure, and durability, as well as flow meter accuracy under various conditions.
Flow meter accuracy is essential to maintaining a safe pool/spa environment for bathers. Early adopters of NSF/ANSI 50 demonstrate leadership in the recreational water industry.
What to watch for in 2013
As mentioned previously, modifications to NSF standards are frequent and ongoing, reflecting the steady evolution of the pool and spa industry. That said, several issues of interest are on the NSF dashboard for 2013 and beyond. The following certification criteria are presently under development or were recently finalized:
Chemicals
Testing and evaluation requirements for various materials (such as coatings, liners, etc.) and the many types of pool/spa water treatment chemicals that are in development.
Heaters
Evaluation, testing, and marking requirements for heat exchangers; heat pump and coolers are being added for natural gas-fired, electrical, passive, and solar-radiant collectors as well as cooling systems.
Variable-speed pumps
Revisions to specify additional pump verification tests, marking, and listing requirements for multi-speed pumps, and pumps that infer or estimate pump flow rate.
Ozone/UV systems
Evaluation and testing requirements for Cryptosporidium (Crypto) disinfection were added to NSF/ANSI 50.
Automatic controllers
Requirements related to interlock with the circulation pump were updated. Many companies are now pursuing certification of automatic controllers to meet new code requirements for NSF/ANSI 50 certification.
Water quality testing devices
Addition of requirements for the evaluation and testing of hardness, total alkalinity (TA), total dissolved solids (TDS), salinity, and other important parameters such as pH, free chlorine and bromine, and total chlorine.
