Water Conditioning & Purification Magazine

Water purification system

Monday, February 15th, 2021

Water, Inc.’s Acuva Eco NX-SILVER Water Purification System is available now for the entire US through Water, Inc.’s dedicated network of 2,500 dealers and distributors. It features the company’s patented UV-LED IntenseBeam Technology, which eliminates up to 99.9999 percent of bacteria and viruses and provides clean drinking water instantly at the point of consumption. When the system is activated, an intense beam of UV light is directed into the water stream to instantly eliminate bacteria and viruses. The system’s built-in instant flow-sensing activation triggers system operation only when the faucet is turned on, extending the product’s longevity. All systems include the water filter as well as mounting equipment, plumbing supplies and power adapter for easy installation in the home, vacation home, RV or boat.

Hands-free water coolers

Monday, February 15th, 2021

Canaletas introduces its hands-free water coolers to offer consumers increased safety and hygienic options. These models are designed to fill bottles by anti-vandalic pedal, double pedal or by a precise proximity sector. The company also offers an economical and easy-to-install pedal kit to convert existing water coolers in hands-free units. Special, extra protective accessories for the taps, spouts and bottle fillers of Canaletas water coolers, which ensure the water never touches the walls of the spout and taps never touch the inside of glasses or bottles, are also available.

Pressurization valve

Monday, February 15th, 2021

Beswick Engineering Co., Inc.‘s rapid pressurization valve is most often used to control a pneumatic actuator such as a chuck, press or gripper. An internal valve component in the RPV restricts the initial movement of the actuator to a user-defined speed. When the actuator contacts the work piece, the internal valve component senses back pressure and opens up. There are two user-adjustable settings in the RPV that allow users to limit the impact a work piece experiences when it is clamped down upon, without sacrificing the pressurization speed of an open, free-flowing connection.
(603) 433-1188

Filter cartridges

Monday, February 15th, 2021

MICRONFilter Cartridge Corp.’s Silver antimicrobial filter cartridges now incorporate FDA-approved AgION® silver ion technology, which inhibits the growth of bacteria, yeast, mold and fungus on the filter media, resulting in improved taste, odor and appearance of drinking water. These cartridges come in numerous sizes. All raw materials and final products are proudly made in the USA. Generic or custom label service available.
(630) 337-3877

Mobile water purification

Monday, February 15th, 2021

Water One, Inc. is expanding sales of its mobile water purification systems. Produced to order and customer specifications, with one or more power sources including solar, wind, generator and direct power, the units can produce a continuous supply of pure drinking water between 2,500-20,000 GPD using surface, brackish and/or saltwater sources. Perfect for remote locations and emerging countries, the units are highly reliable and simple to operate, killing waterborne viruses and bacteria on contact and on demand, as well as eliminating cysts and contaminants.
(239) 425-6100

New Support for Monitoring and Reducing Contamination of Private Well Water Supplies

Monday, February 15th, 2021

By Kelly A. Reynolds, MSPH, PhD

In December 2020, US EPA announced the availability of $1.7 million (USD) in grant funding to provide technical assistance and training to support private drinking-water well owners. According to US EPA Administrator, Andrew Wheeler: “One of EPA’s top priorities is ensuring Americans have safe drinking water, regardless of their zip code.” This investment, in predominantly rural regions, provides support in an area that is technically outside the jurisdiction of the US EPA and the Safe Drinking Water Act (SDWA) that guides municipal water suppliers. Thus, private well owners are responsible for the construction, use, maintenance and testing of their supply. This can be a daunting task given the multitude of hazards that could compromise groundwater quality over time. New support for education and training in private well construction and water treatment, along with new technologies for quality monitoring, promises to improve the safety of well water supplies.

Priority contaminant management
According to US EPA, a private well is defined as a well owned by a homeowner, or group of homeowners, that supplies potable water to less than 25 people via fewer than 15 service connections. Over 13 million households and an estimated 30 million people in America obtain their water from private wells.[1] These groundwater supplies are subject to both microbial and chemical hazards that lead to adverse human health effects. From 1971 to 2010, the US Centers for Disease Control and Prevention (CDC) found that microbes, including hepatitis A virus, Giardia, Campylobacter, E. coli, Shigella, Cryptosporidium and Salmonella were the top causes of outbreaks from wells. Waterborne microbial contaminants are usually spread via ingestion and can cause acute health effects, like stomach flu and diarrhea or more chronic conditions including liver and heart disease, diabetes and arthritis.
The most common chemical causes of well water outbreaks during this same time included arsenic, gasoline, nitrates, phenol and selenium.[2] Routine testing of well water for lead and radioactive contaminants is also recommended. Local test labs can provide a complete list of bacteria, minerals, metals and organic compounds further recommended for your area. Chemical contaminants may cause acute effects such as skin rashes and impaired motor skills or chronic conditions including neurological disorders, developmental disabilities and cancer. Consumers may be exposed to waterborne chemical contaminants via ingestion, inhalation and dermal routes. Exposure to arsenic, a naturally occurring contaminant in soils, rocks and (incidentally) groundwater, can lead to lung, bladder and skin cancers. Arsenic-related cancers are estimated to result in a disease burden cost of $1.6 billion in the US every year.

Well water vulnerability
Most microbial and chemical contaminants are undetectable by taste, sight or smell. A common means of evaluating microbial well water quality includes routine monitoring for coliform or fecal coliform bacteria. Large-scale well water studies have commonly found indicators of fecal contamination in private supplies. A 2018 study in Maryland sampled 118 private wells and found that over 43 percent did not meet federal health-based regulatory standards and over 15 percent tested positive for fecal bacteria.[3] Similar studies in Pennsylvania, Virginia and Wisconsin have also shown that municipal health-based standards for water supplies were exceeded nearly half the time in private well water supplies.
Microbes are the primary cause of private well outbreaks and are associated with some of the highest cost burdens relative to waterborne disease.[4] Microbial indicators, however, do not provide a complete picture of overall water quality and testing for the wide array of possible microbial contaminants can be expensive and time-consuming. Furthermore, testing for fecal indicator bacteria, or specifically E. coli, does not provide information on where the contamination comes from since they are present in the feces of animals and humans. Having a means to track contaminants back to their source would be useful for improved management.

Site-specific tracking tools
For information on wells in your region, including state regulatory requirements, water quality information and testing services, US EPA provides resources organized by links to geographical regions and specific states at https://www.epa.gov/privatewells/private-drinking-water-well-programs-your-state. Different states have varying levels of resources available to help homeowners, including emergency hot lines and extension services. Consumers, however, must navigate these resources on their own and some sites are neither well developed nor user-friendly.
New tools in water quality monitoring have been developed that can assess contamination from the most common sources: agriculture and domestic wastewater systems. Recently, a group of researchers from Ireland published a scientific paper on fingerprinting techniques that use common wastewater chemical profiles to distinguish private well water contamination sources.[5] Different chemical profiles are common to human versus animal wastewater sources. For example, ionic ratios (e.g. potassium/sodium or chloride/bromide), artificial sweeteners, caffeine, fluorescent whitening compounds, fecal sterol profiles and pharmaceuticals occur in different proportions in human and animal wastewater and show promise for source tracking. The fingerprinting method was validated on 212 private well samples testing, 15 percent of which tested positive for E. coli and 54 percent of a sub-sample of 24 samples were contaminated with E. coli at some point over 14 months of extensive monitoring. Low-cost fingerprinting techniques evaluating chloride/bromide and potassium/sodium ratios were useful differentiating tools of wastewater contaminant sources in well water supplies.[5]

Final thoughts
In the US and much of the world, private well water supplies are unregulated, untested and untreated, and consumer awareness of primary protective actions such as water treatment, source maintenance and routine testing is often low.[6] Expanding educational resources and service access may improve such stewardship activities but compliance will still fall short of routine testing requirements for municipalities. Changes in environmental and equipment conditions can result in unexpected contamination events. For many private well owners, a POU treatment system provides an efficient and essential safeguard against exposure to hazards in well water supplies, especially when testing and treatment are non-existent or intermittent.

[1] Paul Haring J., Hernandez L., Trainor B. et al. American Housing Survey for the United States: 2007. Washington, DC, 2008.
[2] CDC, Water Related Diseases and Contaminants in Private Wells. 7 April 2014. [Online]. Available: http://www.cdc.gov/healthywater/drinking/private/wells/diseases.html. [Accessed 11 January 2021].
[3] Muray, R.T., R.E. Rosenberg Goldstein, E.F. Maring, et al. “Prevalence of Microbiological and Chemical Contaminants in Private Drinking Water Wells in Maryland, USA.” International Journal of Environmental Research and Public Health, vol. 15, no. 8, pp. 1686-1698, 2018.
[4] Verhougstraete, M.P., K.A. Reynolds, J. Pearce-Walker, C. Gerba. “Cost-benefit Analysis of Point-of-Use Devices for Health Risks Reduction from Pathogens in Drinking Water.” Journal of Water and Health, vol. 18, no. 6, pp. 968-982, 2020.
[5] Fennell, C, B Misstear, D O’Connell, et al. “An assessment of contamination fingerprinting techniques for determining the impact of domestic wastewater treatment systems on private well supplies.” Environmental Pollution, vol. 268, p. 115687, 2021.
[6] Hynds, P, B. Misstear, L. Gill, “Unregulated private wells in the Republic of Ireland: Consumer awareness, source susceptibility and protective actions.” Journal of Environmental Management, vol. 127, pp. 278-288, 2013.

About the author
Dr. Kelly A. Reynolds is a University of Arizona Professor at the College of Public Health; Chair of Community, Environment and Policy; Program Director of Environmental Health Sciences and Director of Environment, Exposure Science and Risk Assessment Center (ESRAC). She holds a Master of Science Degree in public health (MSPH) from the University of South Florida and a doctorate in microbiology from the University of Arizona. Reynolds is WC&P’s Public Health Editor and a former member of the Technical Review Committee. She can be reached via email at reynolds@u.arizona.edu

NSF/ANSI Standards for Ion Exchange

Monday, February 15th, 2021

By Rick Andrew

Ion exchange has long been one of the important tools in the water treatment toolbox. Recognizing its significance in the industry, a number of NSF/ANSI standards address ion exchange in various ways, depending on the end use and the particular standard involved. In some cases, these standards address only the safety of the ion exchange resin for contact with drinking water, utilizing an extraction (or leaching) test and a toxicological evaluation of any residuals from the manufacturing process or any other contaminants that may extract out during the test. In other cases, the standards go further. In addition to addressing safety of the ion exchange resin, they include test protocols for evaluating the contaminant reduction capability of specific system designs incorporating ion exchange resin. Figure 1 provides an overview of the standards and their applications to ion exchange resins.

Applications of ion exchange resins
Different applications in water treatment utilize various ion exchange resins in different ways. For example, typical POE domestic water softeners use cation exchange resin to exchange sodium or potassium for hardness, primarily calcium and magnesium. Most of these systems are designed and manufactured to be regenerated on site, using pellets of high-purity sodium chloride or potassium chloride. Alternatively, POU perchlorate reduction systems might use a highly selective anion exchange resin in a single-use application, where there is no regeneration of the media and new resin is periodically installed according to a replacement schedule.
Ion exchange treatment also includes important considerations related to the characterization of the water, especially the concentrations of various ions. Ion exchange resins have various selectivity for ions and are impacted by the concentrations of other ions in the water relative to the ion that is intended to be exchanged. For example, although a given ion exchange resin may be more selective to the ion being targeted, other ions (such as nitrate or sulfate) in high concentrations can become problematic by reducing the exchange capacity for the target ion. pH can also be a consideration related to the effectiveness of certain ion exchange resins for exchanging specific ions.

Contaminant reduction protocols
When developing contaminant reduction protocols, it is important to take into account the operation of the treatment technology being tested. For example, is the technology intended for single use and replacement of treatment media or is it intended for on-site regeneration? Another consideration is whether the flow through the system is continuous or near continuous, or is it more intermittent with frequent starting and stopping of flow and periods of stagnation. Other considerations include the impact of water characteristics on the treatment technology. Does the pH impact the effectiveness of treatment? Does the concentration of other ions such as nitrate and/or sulfate impact the effectiveness of treatment?
The goal is to develop a test protocol that is repeatable, reproducible, protective of human health and beneficial to consumers and manufacturers. Each part of this goal has considerations:
• Repeatable. The test protocol must be specific enough such that when the same technology is tested in the same laboratory multiple times, the results are sufficiently similar.
• Reproducible. The test protocol must be described clearly enough such that different laboratories interpret it similarly and achieve results that are sufficiently similar when testing the same technology.
• Protective of human health. The test protocol must be rigorous enough so as to ensure treatment effectiveness under most conditions that could be encountered in real-world applications. When it comes to health effects contaminants, the NSF Joint Committee on Drinking Water Treatment Units has tended toward the 95th percentile, such that 95 percent of end-use cases would be covered by the criteria outlined in the standards.
• Beneficial to consumers and manufacturers. Cost is important. The standards could be developed to attempt to be protective in 100 percent of end-use applications for health effects contaminants (instead of 95 percent), regardless of how extreme the conditions might be. Covering the most extreme five percent of cases, however, would likely lead to over-designing solutions for the other 95 percent of cases, leading to potentially much more expensive technology that would be out of reach for some consumers who could be helped effectively by much less expensive solutions.
Bearing in mind all of these factors, the various standards have specific test protocols designed, specifying the operational cycle, the composition of the test water, the end point of the test, the sample points and the pass/fail criteria.
For applications like water softeners that often include on-site regeneration, the test protocol also involves regeneration. It requires multiple exhaustion cycles with continuous flow, with the regeneration cycle itself also being evaluated for efficiency when demand-initiated regeneration systems make claims of salt and water efficiency.
For applications like POU, single-use (non-regenerable) perchlorate reduction systems, the test protocol includes testing through and beyond the manufacturer’s recommended treatment capacity with samples taken at intervals and with on- and off- cycling of intermittent flow. It also specifies the composition of the test water to include specific concentrations of other ions that could be competing ions or influence the system performance in some way.
Separate test protocols exist for Arsenic III and Arsenic V, with the composition of the test water including specific concentrations of other ions. Reduction of Arsenic III and Arsenic V must each be verified at both high pH (8.5) and low pH (6.5). And as with perchlorate reduction, testing through and beyond a manufacturer’s recommended treatment capacity with interval sampling is required.

A highly scientific approach
Water treatment is complicated. Understanding the complications, the challenges presented by treating certain contaminants with various technologies in water of various compositions and developing solutions that perform well and are cost effective is not simple. The water treatment industry’s role in providing solutions to these complex problems is crucial. Likewise, the standards for verifying the effectiveness of treatment solutions must leverage the knowledge developed by the industry and other stakeholders to develop test protocols that are repeatable, reproducible, protective of public health and beneficial to consumers and manufacturers. Reviewing the standards and their applications to ion exchange technology provides an excellent example of how their development has taken these factors into account to achieve these goals.

About the author
Rick Andrew is NSF’s Director of Global Business Development–Water Systems. Previously, he served as General Manager of NSF’s Drinking Water Treatment Units (POU/POE), ERS (Protocols) and Biosafety Cabinetry Programs. Andrew has a Bachelor’s Degree in chemistry and an MBA from the University of Michigan. He can be reached at (800) NSF-MARK or email: Andrew@nsf.org

A Couple of Culligan Men

Monday, February 15th, 2021

By Emma H. Peterson

Nothing demonstrates the strength of a company like the people who hold its roots. Healthy Water Solutions from Culligan Water was established earlier this year as a partnership between two high-school friends, Rich Johnson and Dave Cone. Johnson had always been with Culligan, while Cone was in the corporate world, but being regular gym buddies and crossing paths in the work sector kept their friendship strong.

Johnson is a third-generation dealer who has worked for Culligan almost 25 years. Growing up, the company had always been a staple in his life. As a kid, he worked for his dad doing route and plant duties. He went to college at Augustana University in Sioux Falls, SD. After a couple of years, he went back to work for his dad, eventually buying him out in 1997. Cone had been a happy Culligan customer for years. His professional background revolved around managing businesses within the technology sector. Cone was CEO of an automation company for six years and held several other similar positions in weighing equipment both in retail and industrial. Johnson earned BS Degrees in business marketing and engineering as well as an MBA.
The pair had long discussed the possibilities of owning a business together, so when the opportunity came to buy the Mankato, Madelia, Jackson and Redwood Falls dealerships as well as a bottling plant, there was no hesitation. With their mutual passion and love of the quality of Culligan products and serving local customers, they were proud to announce Healthy Water Solutions on April 1, 2020. (Within the partnership, Cone can best be described as the numbers guy while Johnson is the out-front guy.) Working together has made them realize their strengths more than ever before.
When the pandemic hit, the partners nearly backed out. They had no idea what was to come of their new expansion in the midst of a worldwide panic. There were many safety precautions put in place to ensure the protection of both customers and employees. They created a policy and procedure to ensure consistency and ongoing safety for all, at every one of their locations daily. “Thus far, we feel we have provided a safe working environment for all. Many of these added precautions and steps will continue even after COVID, as they are simply good business procedures,” Cone said.

Like most of the industry during this time, they have had to modify routes, given the significant number of business closures. And yet, to their surprise, the company has been busier than ever. They have been especially grateful for the involvement of Culligan International, for its assistance and support. The company continues to innovate with products that truly make a difference in the lives of customers. This, combined with class-leading training, allows Johnson and Cone to provide the level of service their customers have come to expect from Culligan water dealers.
Healthy Water Solutions serves nearly all of southern Minnesota with a focus on Mankato, Madelia, Fairmont, Jackson and Redwood Falls. The company’s mission is to help people find a pathway to a healthier life through the consumption of good, clean water. With a focus on both residential and commercial applications, Johnson and Cone provide a wide range of products that include water softeners, iron filters, drinking systems and a full range of bottled water coolers. They are currently in the process of adding deionized (DI) water solutions. The company serves a customer base that has extremely high levels of iron, coupled with very hard water.
Culligan (as a whole) offers many products that when bundled properly, can remove nearly all water contaminants that can contribute to a wide array of health issues. Johnson and Cone’s best-selling product is the industry-leading Culligan HE water softener, which produces average salt and water savings of nearly 46 percent, as compared to competitors’ models.

Their bottling facility uses environmentally friendly, returnable, five-gallon bottles. The company provides bottles to their dealerships to service local customers, as well as many other Culligan dealers across the Midwest. The facility is governed by the US Department of Agriculture, US FDA and Culligan water-bottling guidelines, to ensure their customers are provided clean, healthy water at their homes or businesses.
In the new year, Johnson and Cone are ready to continue to serve their customers in their awesome communities. “I plan to become involved in various organizations that are relevant/related to our industry, as well as local business development organizations within the counties we so proudly serve,” Cone says. Their plan is to continue to grow the business through natural market expansion, as well as through the acquisition of additional Culligan dealerships.

There is much to come for Johnson and Cone. Currently they are working to launch a full array of advanced, high-technology, eco-conscious products from Culligan and they are always on the lookout for new opportunities to expand. “Being in an industry that focuses on providing solutions for improved health makes coming into the office everyday a joy. We have a great team in each location who share our same values. They are dedicated and eager to serve our customers with the same conviction that we have. They are really interested and as motivated as we are to do their part in finding solutions for our customers water needs,” Johnson says. “We have lots to do yet!”

Plumbing Codes Revisited–How They Apply to Water Treatment

Monday, February 15th, 2021

By Thomas Palkon

Revisions to the newly published 2021 plumbing codes have officially begun. As mentioned in the previous article, submittals to propose changes to the 2024 Uniform Plumbing Code (UPC) were due on January 4 and submittals to propose changes to the 2024 International Plumbing Code (IPC) were due January 11. The next step in the process will be for the International Association of Plumbing and Mechanical Officials (IAPMO) and the International Code Council (ICC) to publish the proposed changes and hold the first set of meetings to debate and take the initial vote on the proposals. While we wait for the UPC and IPC code proposals to be published, let’s take a deeper dive into 2021 UPC. Several jurisdictions should begin adopting the 2021 version of the UPC this year, so let’s take a closer look at the requirements that affect the water treatment industry.

2021 UPC – Water treatment devices
The following sections of the UPC pertain to specific requirements that may affect water treatment product compliance to the code. In this article, we have pulled the code language directly from the UPC and provide an explanation of how this section may be applicable to water treatment equipment. The focus will be on the drinking water treatment system, not the plumbing materials used to supply the system or connect to the drain. We will address installation and sizing in a future article.

Chapter 3 – General regulations
Section 301.2 Minimum Standards. Pipe, pipe fittings, traps, fixtures, material, and devices used in a plumbing system shall be listed (third-party certified) by a listing agency (accredited conformity assessment body) as complying with the approved applicable recognized standards referenced in this code, and shall be free from defects. Unless otherwise provided for in this code, materials, fixtures, or devices used or entering into the construction of plumbing systems, or parts thereof shall be submitted to the authority having jurisdiction for approval prior to being installed. This section of the UPC states that if a product standard is specified in the code, testing and certification of the product must be conducted in accordance with the referenced standard and carried out be an accredited certification agency. As an example, this section requires residential water softeners to be tested and certified to NSF/ANSI 44 and commercial softeners to be tested and certified to ASSE 1087 by an accredited certification agency. In the US, there are several certification agencies that conduct testing and certification to these standards, such as IAPMO, NSF International (NSF) and the Water Quality Association (WQA).

301.2.1 Marking. Each length of pipe and each pipe fitting, trap, fixture, material, and device used in a plumbing system shall have cast, stamped, or indelibly marked on it any markings required by the applicable referenced standards and listing agency, and the manufacturer’s mark or name, which shall readily identify the manufacturer to the end user of the product. Where required by the approved standard that applies, the product shall be marked with the weight and the quality of the product. Materials and devices used or entering into the construction of plumbing and drainage systems, or parts thereof shall be marked and identified in a manner satisfactory to the Authority Having Jurisdiction. Such marking shall be done by the manufacturer. Field markings shall not be acceptable. This section of the code requires tested and certified products to be marked or labeled by the manufacturer with the certification agency’s logo and the applicable standard. Many of the drinking water treatment standards have specific marking and labeling requirements that must be followed for the product to be certified, however the certification agency also requires marking the product with their registered certification logo. Most certification agencies publish their marking guidelines so that companies understand the options and requirements for use of the certification mark.

301.2.2 Standards. Standards listed or referred to in this chapter or other chapters cover materials that will conform to the requirements of this code, where used in accordance with the limitations imposed in this or other chapters thereof and their listing. Where a standard covers materials of various grades, weights, quality, or configurations, the portion of the listed standard that is applicable shall be used. Design and materials for special conditions or materials not provided for herein shall be permitted to be used by special permission of the Authority Having Jurisdiction after the Authority Having Jurisdiction has been satisfied as to their adequacy. A list of plumbing standards that appear in specific sections of this code is referenced in Table 1701.1. Standards referenced in Table 1701.1 shall be applied as indicated in the applicable referenced section. A list of additional approved standards, publications, practices, and guides that are not referenced in specific sections of this code appear in Table 1701.2. An IAPMO Installation Standard is referenced in Appendix I for the convenience of the users of this code. It is not considered as a part of this code unless formally adopted as such by the Authority Having Jurisdiction. This section explains that Table 1701.1 and Table 1701.2 provide a list of all the product standards covered in the UPC. Table 1701.1 includes all the standards that are also referenced in specific sections of the UPC. For example, ASSE 1087 is listed in Table 1701.1 because it is also referenced in Section 611.1. Table 1701.2 includes approved standards for products that do not include additional code language in other sections. When looking for a product standard covered in the UPC that relates to a specific drinking water treatment product, these two tables provide an excellent resource, as they include all the product standards referenced in the UPC.

310.2 Drainage and Vent Piping. No drainage or vent piping shall be drilled and tapped for the purpose of making connections thereto, and no cast-iron soil pipe shall be threaded. This section is most relevant for residential RO systems. It is common for manufacturers to include drain and supply saddle valves. The UPC prohibits the use of drain connections that require the installer to drill into the drain line to connect the RO reject line. Code-compliant installation for RO drain lines requires the use of a certified drain adapter fitting and an air gap or air gap device.

Chapter 4 – Plumbing Fixtures and Fixture Fittings
408.0 Showers.
408.1 Application. Manufactured shower receptors and shower bases shall comply with ASME A112.19.1 / CSA B45.2, ASME A112.19.2 / CSA B45.1, ASME A112.19.3 / CSAB45.4, CSA B45.12/ IAPMO Z402, or CSA B45.5 / IAPMO Z124. Prefabricated shower enclosures shall comply with IAPMO IGC 154. Shower filters that are integrated into a shower head are required to comply with ASME A1121 / CSA B45.2. Many shower filters companies list their product to NSF/ANSI 177 to demonstrate the products’ ability to reduce chlorine; however for code compliance, the filter and shower head also need testing and certification to ASME A1121/CSA B45.2.

408.2 Water Consumption. Showerheads shall have a maximum flow rate of not more than 2.5 gpm at 80 psi (9.5 L/m at 552 kPa). Shower filters that are incorporated into a shower head shall not have a flowrate of more than 2.5 gpm to comply with the UPC. As a side note, however, the state of California requires shower flowrates of not more than 1.8 gpm.

417.6 Low-Pressure Water Dispenser. Beverage faucets shall comply with ASME A112.18.1 / CSA B125.1. Low-pressure water dispensers that dispense electrically heated water and have a reservoir vented to the atmosphere shall comply with ASSE 1023. Electric devices that heat water shall comply with UL 499. Recently revised, ASSE 1023 now covers hot and cold water dispensers, with or without water filters, which is also covered by this section of the UPC. Hot water dispensers with or without water filters require testing and certification to ASSE 1023. Manufacturers of hot and cold water coolers should review ASSE 1023; if their product is plumbed in to a supply line, certification to ASSE 1023 is required.

Chapter 6 – Water Supply and Distribution
603.0 Cross-Connection Control.
603.1 General. Cross-connection control shall be provided in accordance with the provisions of this chapter. No person shall install a water-operated equipment or mechanism, or use a water-treating chemical or substance, where it is found that such equipment, mechanism, chemical, or substance causes pollution or contamination of the domestic water supply. Such equipment or mechanism shall be permitted where equipped with an approved backflow prevention device or assembly. The UPC includes detailed requirements on backflow protection. The cross-connection control sections are relevant for water softeners, RO systems and other products, such as POE backwashing filters that have a drain connection. The simplest and one of the most effective cross-connection control techniques is the use of an air gap. When connecting a water softener drain line or backwashing filter drain line, the use of an air gap is required to comply with the UPC.

603.3.1 Air Gap. The minimum air gap to afford back-flow protection shall be in accordance with Table 603.3.1. An air gap is a physical gap in space between the drain line of water treatment device or an RO reject line. Several companies have also developed air gap devices that simplify the installation of a water treatment system’s drain line and the waste piping. A physical air gap or an approved air gap device are required to comply with the UPC when connecting drain lines.

603.4.6 Integral Backflow Preventers. Fixtures, appliances, or appurtenances with integral backflow preventers or integral air gaps manufactured as a unit shall be installed in accordance with their listing requirements and the manufacturer’s installation instructions. An example of an integral backflow preventer is an air gap faucet that is used with POU RO systems. The use of an air gap faucet that has been tested and certified to NSF/ANSI 58 is a simple way to comply with the cross-connection requirement of the UPC. When connecting the drain line to the plumbing below the sink, however, do NOT drill into the drain line and use a drain saddle. A certified drain fitting must be used and there are many available options that include push-fit fittings for quick and simple installations.

603.5.12 Beverage Dispensers. Potable water supply to beverage dispensers carbonated beverage dispensers, or coffee machines shall be protected by an air gap or a vented backflow preventer that complies with ASSE 1022. For carbonated beverage dispensers, piping material installed downstream of the backflow preventer shall not be affected by carbon dioxide gas. Water treatment devices that include a carbonation option continue to increase in popularity in the US. If a water treatment device includes an option to dispense carbonated water, it will need to be tested and certified to ASSE 1022. There are, however, commercially available ASSE 1022-certified backflow preventers that can be used with the water treatment system for compliance to the code.

603.5.18 Pure Water Process Systems. The water supply to a pure water process system, such as dialysis water systems, semiconductor washing systems, and similar process piping systems, shall be protected from back-pressure and backsiphonage by a reduced-pressure (RP) principle backflow preventer. Cross-connection control for ultrapure water systems used for dialysis, laboratories, bottled water plants or other applications require an RP backflow preventer. When using an RP, it is important to note that several states also require the RP to be tested by a licensed professional one time per year. RPs provide the necessary safety to ensure the process water will not reverse flow and enter the potable water plumbing.

604.0 Materials
604.1 Pipe, Tube, and Fittings. Pipe, tube, fittings, solvent cement, thread sealants, solders, and flux used in potable water systems intended to supply drinking water shall comply with NSF 61. Where pipe fittings and valves are made from copper alloys containing more than 15 percent zinc by weight and are used in plastic piping systems, they shall be resistant to dezincification and stress corrosion cracking in compliance with NSF 14. Although we are not covering in detail the installation of water treatment devices, the UPC requires the pipe, tubing and fittings to comply with NSF/ANSI 61 when connecting the supply line of a water treatment device. Plastic pipe and fittings shall also comply with NSF/ANSI 14. Material safety of the water treatment device itself is covered by the performance standards referenced in the code.

604.2 Lead Content. The maximum allowable lead content in pipes, pipe fittings, plumbing fittings, and fixtures intended to convey or dispense water for human consumption shall be not more than a weighted average of 0.25 percent with respect to the wetted surfaces of pipes, pipe fittings, plumbing fittings, and fixtures. For solder and flux, the lead content shall be not more than 0.2 percent where used in piping systems that convey or dispense water for human consumption. The UPC requires products that contact water for human consumption to comply with the Safe Drinking Water Act’s weighted averages requirements for lead content. US EPA recently announced that all drinking water treatment products will need to comply with US EPA’s lead-free law, which now includes testing and certification of the equipment. NSF/ANSI 372 is often used by companies and certification agencies to test and certify water treatment products for lead-free compliance.

611.0 Drinking Water Treatment Units
611.1 Application. Drinking water treatment units shall comply with the applicable referenced standards in Table 611.1.
611.1.1 Alkaline Water Treatment. Alkaline water treatment devices shall comply with IAPMO IGC 322.
611.1.2 Scale Reduction Devices. Scale reduction devices shall comply with IAPMO Z601.
This section of the UPC provides the specific language of the product standards listed in the code. Table 611.1 lists the product standards covering residential and commercial, POU and POE filters, residential and commercial water softeners, residential and commercial UV systems, residential and commercial RO systems and residential and commercial distillation systems. This section also specifies the standard used for certification of alkaline water treatment products and the standard used for certification of scale-reducing products.

611.2 Air Gap Discharge. Discharge from drinking water treatment units shall enter the drainage system through an air gap in accordance with Table 603.3.1 or an air gap device that complies with Table 603.2, NSF 58, or IAPMO PS 65. This section repeats some of the cross-connection control requirements specific to water treatment devices. Air gaps are required for drain connections or certified air gap devices such as an RO air gap faucet, certified to NSF/ANSI 58. This section also provides the reference standards used for air gap devices that cover water treatment equipment.

611.3 Connection Tubing. The tubing to and from drinking water treatment units shall be of a size and material as recommended by the manufacturer. This section specifies that tubing recommended by the manufacturer shall be used to install the water treatment device; however Section 604.1 also requires that the pipe, tubing and fittings be certified to NSF/ANSI 61 and NSF/ANSI 14 for plastic pipe, tubing and fittings.

611.4 Sizing of Residential Softeners. Residential-use water softeners shall be sized in accordance with Table 611.4. This table provides a sizing chart for residential water softeners. We will dedicate a future article on proper sizing of POE equipment for residential and commercial water treatment equipment. In that article, we will walk through Appendix A and Appendix C along with IAPMO’s WeStand code.

Although the water treatment industry is not heavily regulated at the federal level, plumbing codes are enforced in many state and local jurisdictions. When installing water treatment equipment, it is important to understand the plumbing code requirements to avoid red tags or fines. This article provides a review of the primary sections of the UPC that address water treatment industry products. There are numerous changes in the 2021 version of the UPC for water treatment equipment when comported to the 2018 version. Companies should review the 2021 code to determine if any additional testing and certification will be required on their products and to understand proper sizing and installation requirements. If you have specific questions, IAPMO offers a variety of options for code questions and answers. We are always happy to assist.

About the author
Thomas Palkon is the Executive Vice President and Chief Technical Services Officer for the IAPMO Group and ASSE International Executive Director. He joined IAPMO in 2014. Palkon has over 20 years of experience in the water treatment industry, with expertise in product testing, product certification, standards development, professional qualification standards development, professional certification, government affairs and international operations.

The Chemistry of Ion Exchange

Monday, February 15th, 2021

By C.F . ‘Chubb’ Michaud, MWS

Chemistry 101: elements, compounds, acids, bases, salts and ions
All of the chemicals listed in The Periodic Table of the Elements (see Figure 1) are made up of atoms, which are combinations of electrons (negative charge), protons (positive charge) and neutrons (neutral charge). The protons and neutrons are contained in the nucleus of the atom. The electrons surround the nucleus as more of a charged cloud. Electrons and protons are always equal so all elements are neutral. The total number of protons determines the atomic number (AN) and the combination of protons plus neutrons determines the molecular weight (MW or atomic weight AW) of the element. Since the elements are neutral, the compound they form by combining is also neutral. Example: sodium (Na) is Element #11. It has 11 protons and 11 electrons. It also has 12 neutrons so it has an atomic number of 11 and a MW of 23. When it reacts with chlorine (Cl) (Element #17 with a MW of 35.5) it forms a compound (sodium chloride, NaCl), which is also neutral and has a MW of 58.5, the total of the two components. Chlorine is found in nature with two primary isotopes (variants of a chemical element that differ in neutron number). One has 18 neutrons and the other has 19 and they are found about equally distributed. The average MW is, therefore, the sum of the protons (17) plus the average of the neutrons (18.5) for an average MW of 35.5.

When elements react with water (H2O), they can form acids and/or bases. Chlorine (Cl) would form an acid (HCL and HOCl) and sodium (Na) would form a base (NaOH) as shown in the following reactions:
Reaction 1: Na + H2O → NaOH + H↑ hydrogen gas is liberated and sodium hydroxide is formed.
Reaction 2: Cl2 + H2O → HCl + HOCl hydrochloric and hypochlorous acid are formed.
When acids and bases react together, they form salts plus water:
Reaction 3: NaOH + HCl → NaCl + H2O the product of neutralization is salt plus water.
When salt is dissolved in water, it dissociates into ions that are charged particles. The positive ions are called cations and the negative ions are called anions. The charge is due to the gain or loss of negative electrons.
Reaction 4: NaCl + H2O → Na+ + Cl + H+ + OH the plus and minus charges are equal.
With dissociation, sodium loses one electron (loss of a negative charge) and becomes positive (sodium ion) (see Figure 2). Chlorine gains one electron and becomes negative (chloride ion). These are written to show the charge as Na+ and Cl. We refer to this level of charge as the valence of the element or ion. Valence is determined by the number of electrons lost or gained when ionized and is typically limited to only the outer orbit of the atom. The valence values are typical of the element but not fixed. Nitrogen, for instance, has a valence of -3 when combined with hydrogen to form ammonia gas (NH3). However, when it combines with oxygen to form the nitrate ion (NO3), it has a valence of +5. That’s because nitrogen (Element #7) is an atom with five electrons in its outer orbit. To satisfy its outer orbit, it can either give up five electrons (becoming positive +5) or pick up three electrons (becoming negative -3). At the lower AN ends of The Periodic Table of the Elements columns, the magic number for electrons is an inner orbit of two and outer orbit of eight (see Figure 2).
When elements react with one another, they do so on the basis of their equivalent weights (EW). EW is a real weight number that equates how much of element A is required to react with X amount of element B. In our molecule example shown in Figure 2, it would take 23 grams (or milligrams or pounds or tons) of sodium metal to fully react with 35.5 grams (or pounds, etc.) of chlorine gas to form 58.5 grams, etc. of sodium chloride. The MW of an element divided by its valence equals its equivalent weight. This is very important when dealing with ion exchange reactions and multivalent ions (having a valence >1), such as calcium, magnesium, sulfates and arsenic.
Example: How much sodium is put into a water stream from a softener treating 80 mg/L of calcium and 24 mg/L of magnesium? The MW of calcium is 40 and the valence is 2 (EW = 20). The MW of magnesium is 24 and the valence is also 2 (EW = 12). The MW of sodium is 23 and the valence is 1 (EW = 23). So we have EW for calcium of (40/2 =) 20 and magnesium is (24/2 =) 12. Sodium is (23/1 =) 23. In numbers of equivalents, we have 80/20 = 4 for calcium, 24/12 = 2 for magnesium. So we will exchange 4 + 2 equivalents of hardness for 6 equivalents of sodium. Thus: 6 x 23 = 138 mg. We took out 120 mg/L of hardness and replaced it with 138 mg/L of sodium. We did increase the TDS but we did not increase the number of equivalents (i.e., the number of ions or ppm as calcium carbonate: CaCO3).
A single atom of any element is identifiable as that element. Gold is made up of the same electrons, protons and neutrons as helium, yet they are very different. Alchemists have been trying to change that for centuries. Each element has a unique combination of electrons, protons and neutrons that determines its properties and how it behaves in a chemical reaction. Elements with similar behavior form families and are represented as a single vertical column on The Periodic Table of the Elements. An example is the halide family (column 17): fluorine, chlorine, bromine and iodine, all unique but each with similarities to the others. Another example is the inert gases (column 18): helium, neon, argon, krypton, xenon and radon. These elements are very happy by themselves and do not react with others.
Once a salt is dissolved in water, it is no longer associated with its counter ion (the partner it came in with). A mixture of calcium chloride, magnesium sulfate and sodium bicarbonate will dissolve, dissociate and become six different and independent ions. Different elements from different columns of The Periodic Table of the Elements will have different molecular weights and different valences due to electron transfers when they become dissolved in water (ionized). This difference in charge and weight gives them higher and lower selectivity (reactivity preference—the higher charge and higher MW will generally increase the ionic selectivity) when combining with other ions, which can determine their solubility or volatility. This is the basis for the equilibrium in an ion exchange reaction. This is also the reason why ion exchange works.

Putting atoms in perspective
Single atoms of elements are extremely small; so small, in fact, that their size is hard to comprehend in terms of measurements with which we are familiar. If we take a standard such as the meter (one-ten-millionths of the distance from the Equator to the North Pole) and divide it into 1,000 parts, we have the millimeter (mm). We use mm to measure granular filter media, such as activated carbon. Divide that by 1,000 and we now have the micron (µm). We use microns to measure even smaller particles that we can still see (ion exchange resins are typically 300 to 1,000 µm) and some that we cannot see without a microscope (bacteria are in the 1-100 mm size range). Human blood cells are around the 8-µm range. Dividing a single micron by 1,000 gives us the nanometer (nm). You could fit about 100,000 of them inside the period at the end of this sentence (side by side). That’s getting down there but in terms of molecules, it’s still pretty big. Divide the nm by 10 and we get a unit of measure called the angstrom (Å), which is one-ten-billionth of a meter. Now we are at a molecular size level. Hydrogen is only 0.25 Å in diameter; sodium and potassium are much larger at about 2 Å. Atoms are mostly space in that the nucleus of an atom is only about one-ten-thousandths (1/10,000) of its total diameter. The electron cloud has volume but is not considered to have much mass. Picture, if you will, a hot air balloon 10 meters (about 33 feet or 10,000 mm) in diameter (with a volume of >500 m3). Place a single grain of sand in the center of the spherical balloon and a tiny speck of dust on the outer surface. You have a proportioned model of the hydrogen atom with the grain of sand representing the size of the nucleus and the dust particle representing the electron cloud. This helps paint the picture that our universe and everything in it is pretty much void space.

Avagadro’s Constant
Amedeo Avagadro (1776-1856), was an Italian physicist active in the early 19th Century. In 1811, Avagadro made the observation that “equal volumes of different gases at the same temperature and pressure, have the same number of molecules.” This became known as Avagadro’s Law. Over the next century, several brilliant scientists using different methods to do the calculations answered the $64 question: How many molecules are present in a gram-mole of any element? A gram-mole of any substance is the quantity of that substance, measured in grams, that is equal in number to the MW of that substance (i.e., 12 grams of carbon, 1 gram of hydrogen, 197 grams of gold). The answer is 6.022 x 1023 (that’s 602,200,000,000,000,000,000,000) and is given the name Avagadro’s Number (NA) to honor the physicist.
If you divide the quantity of the value for a gram-mole of any element by its valence, you derive a number that represents the gram-equivalent weight for that substance. Calcium has a MW of 40 and valence = 2. The EW for calcium is (40/2 =) 20 and the gram-equivalent is 20 grams. This is an important relationship because in ion exchange chemistry, capacity is given as milli-equivalents/milliliter (meq/mL). This is the same as a gram-equivalent/liter or eq/L. A capacity value of 1.0 meq/mL means that an ion exchange resin would have the capacity to hold 20 mgs of calcium per milliliter of resin or 1.0 equivalent of calcium per liter of resin (1.0 equivalents of calcium = 20 gms).

Ion exchange resins
An ion exchange resin is a polymer (plastic), usually used as a small bead (about 0.5 mm [500 µ]) that contains a fixed, insoluble matrix as part of the bead structure and a movable or replaceable mobile ionic component that can be exchanged for other mobile ions in solution. The degree of the exchange is a variable that is driven by the previously mentioned selectivity. Calcium, for instance, forms a divalent ion (Ca+2) that has a stronger attraction to the exchange matrix than does monovalent sodium (Na+1). Therefore, if a solution containing Ca+2 is passed through a bed of resin in the Na+1 form, the matrix will pick up the more selective Ca+2 and release the less tightly held Na+1. This is how and why a softener works.
Reaction 5: Ca(HCO3)2 + O-Na ↔ O-Ca + NaHCO3 the softening reaction. The ↔ indicates that the reaction is reversible.
Reaction 6: O-Ca + NaCl ↔ O-Na + CaCl2 + NaCl the regeneration reaction showing excess salt used.
Softening resins are quite small, measuring only about 600µ (0.6mm) in diameter. It is calculated that you can fit 6,891,038 of them into a one-liter beaker. Each tiny bead has 1.75 x 1017 reactive sites inside. Fully saturated, a cubic foot of cation softening resin can hold 56.64 equivalents of pure calcium hardness. That’s almost two and a half pounds (56.64 x 20 = 1,132.8 gms).

In The Periodic Table of the Elements, starting in the upper left with Element #1 (hydrogen), the farther down the table you go and the farther to the right, the higher the selectivity for cation species. Many elements form anionic species. As a rule, non-metals such as sulfur (S), phosphorous (P), carbon (C), Silica (Si) and arsenic (As) will combine with oxygen and become oxy-anions (generally with ‘ate’ or ‘ite’ in the name). The halogen family will form anions (without oxygen they form ‘ides’). Figure 3 is a table[2] showing the relative selectivity of selected ions on a typical 8-percent, cross-linked cation (softening) resin operated in the sodium (Na Salt) form and a Type I dealkalizing resin operated in the chloride form. (SAC stands for strong acid cation and SBA stands for strong base anion.)

What can go wrong?
Yes, you can use an ordinary softener regenerated with salt (NaCl) to remove ammonium from feed water because the selectivity for ammonium (NH4+) is higher than that of sodium (Na+) (1.29 versus 1.0). But what happens as the resin approaches exhaustion and/or you have hardness present (the selectivity for calcium [Ca] and magnesium [Mg] is much higher than that of ammonium [NH4]) (2.61 and 1.66 versus 1.29)? You will dump ammonium, perhaps at levels of 5-10 times that of the feed water. The same holds for nitrite and nitrate in a high-sulfate water. There’s no need to worry about radium being removed by a softener because the radium has a much higher selectivity than does hardness (13.0 versus 2.61 and 1.66). It’s the same for uranium over sulfate. Make sure you understand the sequences in which ions are picked up and released by ion exchange resins. The selectivity on SBA for chrome +6 (CrO4-2) is 100. It is far more selective than sulfate and will be picked up preferentially even after the resin has exhausted on sulfates. The selectivity for arsenic +5 (HAsO4-2) is 4.5. That is lower than that of sulfate (6.1).* Be careful! Reduce your capacity setting to make sure you don’t exhaust the resin to avoid dumping high levels of arsenic back into the treated stream.
* The selectivity of certain ions changes with the configuration of the specific anion resin. Type Is have a different selectivity order and absolute relative value than Type IIs. The same goes for weak base resins in a DI train. There have been great strides in the last 25 years towards the development of anion selective resins and ion exchange adsorbants with very high selectivity for nitrates, arsenic, perchlorates, uranium, chromate, and others.[3]

Ion exchange is an excellent media for the selective removal of contaminants. Ion exchange works on the principle of positive and negative charge attraction and selectivity. Selecting a proper ion exchange treatment, however, is a bit more inclusive than simply buying what sounds like the correct resin off the Internet. The best advice is to talk to those familiar with proper design. Do your homework and don’t be afraid to ask questions. When you are dealing with carcinogens and toxic elements, you can’t afford to fail.

[1] Definition of Femtometer and proton diameter. Wikipedia.
[2] Michaud, C.F. “The Basics of Chemistry-Part 3,” WC&P International, June 1998.
[3] Purolite. Technical Capabilities Handbook, Purolite Co., Bala Cynwyd, PA

About the author
C.F. ‘Chubb’ Michaud, Master Water Specilaist is the Technical Director and CEO of Systematix Company of Buena Park, CA, which he founded in 1982. He has served as chair of several sections, committees and task forces within WQA, is a Past Director and Governor of WQA and currently serves on the PWQA Board, chairing the Technical and Education Committees. Michaud is a proud member of both the WQA and PWQA Halls of Fame, has been honored with the WQA Award of Merit and is a two-time past recipient of the PWQA Robert Gans Award. He can be reached at (714) 522-5453 or via email at AskChubb@aol.com.

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