Article #5:
Practical POU Chlorination.
Consumers believe chlorine is cheap, effective, familiar, and can be safely removed from drinking water. Whether these factors translate into success for POU chlorination remains to be seen.

Chlorination remains, by far, the predominant drinking water treatment of choice worldwide. This is true despite chlorine's taste and odor, a growing awareness of its limitations against certain pathogens (such as giardia and cryptosporidium), a rising concern about Trihalomethanes (THMs) and other by-products, and technical advances that have made alternative methods of disinfection (in particular, iodinated resin, ozonation and ultraviolet light) practical for all size systems.

Nevertheless, chlorination has failed to make significant progress as a Point-Of-Use (POU) treatment until quite recently. To be certain, central and Point-Of-Entry (POE) chlorinators are popular treatment products, especially for well water users. In most cases, chlorine tablets or solution have been added to a holding tank or well that can endure long-term exposure to often high levels of chlorine. This, of course, can represent a significant portion of the system's cost.

Moreover, the commonly available methods of chlorination present a choice between periodically adding chlorine or providing controls which consistently add carefully metered levels of chlorine (i.e. injector pumps). Using the first method, when the chlorine is first added, chlorine levels are at their highest; as time passes, dilution occurs and chlorine levels decline. This can present a problem for maintaining consistent, adequately disinfected water.

On the other hand, reliably providing an ongoing discharge of chlorine requires complex, often expensive, metering devices. Chlorine is added, often electronically, based upon the volumes of water actually used. Time release methods have been tried as well. However, chlorine is not expended over a specific and predictable time period. It lasts for varying time periods depending upon water conditions and volumes. Thus, adequate chlorination is not assured by time release. Under either scenario therefore, individual vigilance (most critically, periodic testing), is necessary to assure adequate disinfection.

The POU Challenge
Developing marketable POU chlorinators has proven to be a daunting task. First, like all water treatment products, POU systems must be affordable. However, since these systems treat lower water volumes than their POE cousins, amortizing the cost of expensive holding tanks or controls is more expensive on a per unit basis.

Larger systems also produce and store enough water to allow for reasonable time periods to elapse from one scheduled chlorine addition date to the next, or from one scheduled testing day to the next. Thus, central systems can be monitored by home or business owners infrequently enough so as not to present an unacceptable burden, and water treatment companies can provide this service as part of a maintenance contract at a reasonable cost.

A POU consumer, however, cannot reasonably be expected to test with the frequency, or pay for the service necessary, to adequately assure the performance of systems using any of the traditional methods of chlorination.

More important than any of these considerations, however, is that central systems store large volumes of water, thus helping to assure longer exposure of the source water to the chlorine. Like all halogens to varying degrees, chlorine requires time to kill pathogens.

POU treatment, however, generally occurs rapidly, at or around the time of use. To add chlorine, and then to rapidly remove it, does little to ensure drinking water safety. While many POU iodinated resin systems are currently marketed that perform in this manner, they have succeeded only because of misleading claims that iodine miraculously kills all microorganisms instantly. It does not, and neither does chlorine. The major difference is that we are all sufficiently familiar with chlorination so as not to be fooled.

Therefore, to succeed, a POU chlorinator would need to be cost-effective, provide storage for adequate exposure time, and somehow deliver reliable amounts of chlorine in a convenient and demonstrable way.

The need for residual disinfection
In most chlorination systems, the mechanism selected to extend exposure time to ensure proper disinfection is simply to leave residual chlorine in the water. This serves a second, and separate, critical function: protection against re-contamination.

Disinfected water, of course, is not sterile. Instead, bacteria and other waterborne pathogens are simply reduced dramatically to benign levels. Thus, as the U.S. Environmental Protection Agency (USEPA) warned in its 1983 report "Microorganism Removal for Small Water Systems," "...if the treated water enters a distribution system and there is no residual disinfectant remaining in the water, those surviving organisms that find a suitable living environment . . . may grow and reproduce."

That is of course why our municipal water supplies contain residual chlorine. POU systems, however, cannot simply leave chlorine in the drinking water. While larger scale systems may be marketable on the basis of safety claims alone, a POU system that produces foul-tasting water (and one that fails to remove harmful THMs), is doomed to failure.

Therefore, chlorine must be removed by the POU chlorinator system. For small-scale systems operated at the point of use, this requirement creates a "catch-22" situation. How does one create a POU chlorination system that ensures adequate exposure and residual disinfection while removing chlorine at virtually the same location?

Physics and pressure feeding
At the March, 1995 WQA Convention and Exhibition in Nashville, at least two companies boasted POU chlorinators that operate on a completely different principle to provide reasonably consistent chlorination, within acceptable ranges, without the need for electronic metering devices. While the overall systems differed dramatically, the metering process in each was controlled by water pressure alone.

In one system, pressure differentiation is used to control the addition of chlorine. A water line is split to flow both through and around the chlorinator unit. An environment is then established through the use of a nonporous bladder, such that the line pressure behind the chlorinator exceeds that flowing around the chlorinator. Through the natural process of passive transport, the more highly pressurized water flows into the less pressurized water, seeking to establish an equilibrium. By carefully controlling the pressure differential, the homeowner can assure controlled chlorine elution.

The other system, which was introduced commercially at the WQA convention, provides a mechanical metering device which is complex to manufacture yet elegant in the simplicity of its design. In this instance, line pressure is once again split to cause separate flows through and around the chlorinator device. However, in this system, a semi-porous micro-dropper tip, designed initially for pharmaceutical testing, is inserted at the distal end of the chlorinator. Line pressure then forces minute volumes of chlorine solution out of the dropper in an amount regulated by the size and porosity of the aperture selected.

Exposure, residual and taste
Mastering the art of consistent elution without electronic meters or pumps solved half of the challenge. However, as noted above, to make POU chlorination practical, one would have to: 1) assure adequate disinfection; 2) retain residual chlorine to protect against post-treatment recontamination; and 3) still remove chlorine prior to consumption. This triumvirate led to a single inescapable conclusion: The chlorinated water produced would have to be stored with the residual chlorine, and in large enough volume, to help ensure adequate exposure time. Then, the water would have to be dechlorinated as it was dispensed. This, however, raised serious cost concerns.

The products introduced at the WQA convention address this concern through the use of plastics and gravity. While conceptually quite different, each system made use of a commercial grade, FDA-approved plastic material for a storage tank. While less practical for large systems, at the point of use these materials are sufficiently cost-effective and durable to substitute for costly alternatives. By using dispensers that place the storage tank on top and carbon filtration at the bottom, no pumping device or line pressure is necessary to force the water through the chlorine removal media. Instead, gravity alone - or head pressure, if you prefer - serves that role.

Inventing is not commercializing
These promising devices are still in their nascent stages. Whether the market accepts POU chlorination after hearing for so long that it was expensive and impractical remains to be seen.

What is clear, however, is that while consumers grow ever more concerned about drinking water quality, relatively few have embraced alternative disinfection methods. While ozonation, iodination and ultraviolet disinfection methods have grown into potent market forces within the POU/POE industry, they continue to represent only a small fraction of the overall drinking water disinfection market.

What consumers do believe in large numbers is that chlorine is cheap, chlorine works, chlorine is common and familiar, and chlorine can safely and effectively be removed from drinking water. Whether these factors translate into success for the emerging discipline of POU chlorination is yet to be seen.

Steven G. Singer is chairman of SemperPure Systems, Inc., Master Distributors for Pure 1 Systems based in Billerica, Mass. He is a graduate of the Harvard Law School and the University of Penn. Before joining Semper-Pure Systems, Singer spent more than six years in the health care industry, most recently as CEO of a NYSE-listed conglomerate, and has conducted business extensively around the globe.


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Article #6:
POU Ozonation Disinfection.
The benefits of ozonation as a method of drinking water disinfection have come to be well documented and understood. More than 100 years after the first ozone system was successfully employed, the water challenges of the 90's have refocused the industry's search for ozone solutions, and the results have been extraordinarily positive.

Ozone is, according to currently available data, uniquely effective at destroying giardia and cryptosporidium cysts. While micro-filtration can do much or all of what ozone can do in this area, ozone reduces the inconvenience of such filtration. While highly effective, some users consider micro-filtration to be unappealing due to its need for frequent filter replacement (when using disposable filters) or frequent (and potentially hazardous) filter cleansing (when using re-usable filters). Ozone is also a most powerful oxidizing and disinfecting agent, far more potent than either chlorine or iodine. It is, therefore, capable not only of rapid pathogen destruction, but the conversion of organic compounds, permitting the removal of their unwanted taste, odor and color. And, unlike ultraviolet irradiation, ozone has no risk of shadowing, the phenomenon of pathogens "hiding" from the UV lamp in the protective penumbra of particulate matter or bacteria clumps.

So persuasive has been the argument in favor of ozonation that, according to published literature, its use in domestic water treatment plants has grown more than 20-fold in this decade alone. It has become the dominant disinfection technology among drinking water bottlers world-wide.

The ozonation market
Even with its broad disinfection and oxidation powers, ozone is not a panacea. It cannot perform the types of purification associated with reverse osmosis (RO) and distillation, or the polishing accomplished through ion exchange processes. Therefore, ozone is often used in conjunction with one or more of these other processes, especially within the bottled water industry.

To gauge the growth of ozone within the water treatment industry, one needs only to examine recent back issues of WC&P and other trade publications. The number of articles and advertisements related to ozone technology systems or components has begun to rival those related to RO and even Granular Activated Carbon (GAC).

POU ozonation challenges:
cost and technology
However, as with all predecessor chemical disinfectants, ozoneÕs growth in the small-scale point-of-use (POU) water treatment market has lagged well behind that at the industrial, commercial and point-of-entry (POE) level. Indeed, there are very few ozone systems on the market today that are point-of-use. Others, though labeled as POU, appear to be nothing more than larger scale systems, offered as a costly secondary application which fails to utilize its full capacity.

The two major challenges in introducing POU ozone systems are technical constraints and, as with all POU products, cost.

Cost
Cost, perhaps trailed most closely by ease-of-use is always the major consideration for POU buyers. These potential buyers are often home or business owners, unwilling or unable to invest in capital equipment to reduce long-term expense. Indeed, despite a growing cadre of educated dealers and consumers, retail purchasers of POU systems still do not, at least generally, focus on overall operating cost and cost per unit of volume. Instead, they most often focus on absolute cost-what does it cost up front and how much will the next payment run.

To verify this proposition, one only need look at two case studies. Consider the bottled water market. Water is sold in small volume (a maximum of five gallons) at prices anywhere from $1 to $3 per gallon. Despite the enormous growth of our industry, a majority of consumers prefer to fork over a few dollars at a time for bottled water rather than make an economically superior investment in a treatment system.

Consider also the wild growth of the Brita® pour-through carafe product. How can one explain consumers enthusiastically paying approximately $7.50 for a carbon filter with a 30 gallon life span? The answer is simple, if not elegant: each new system costs only $30.

With larger scale systems, purchasers must, and do, consider a bigger picture. Once the decision has been reached to make the capital investment and to amortize the cost over a long period of time and large number of gallons, it is less difficult to begin to address more esoteric issues. Issues like: quality; relative efficacy; the durability of non-replacement parts; the life span of exhaustible/replacement components; excess capacity for peak load usage; system flexibility for future expansion; and so forth. These considerations, and the trade-offs that purchasers are willing to make, permit the broad range of systems-and prices-that we see today. But, with small scale POU, cost is still king. Whether this is a good or bad thing for our industry may be the subject of future columns. For now, however, the critical fact is that this is the environment in which the POU system dealer must sell.

Within the context of this price competitive market lives the undeniable truth, to the chagrin of POU manufacturers, that some things are simply not less expensive when manufactured in a small size. Indeed, the opposite is often true. And, the "off-the-shelf" components available to those manufacturers are almost always larger than needed for POU applications. Consider, for example, commercially available chlorination devices. From fancy electronic injection pumps to economical chlorine tablets, I defy you to find any two that are appropriate&emdash;either in capacity or cost-for a 10 to 50 gpd system.

Similarly, commercially available ozone generating UV lamps or corona discharge devises, diffuser pumps and ozone tolerant holding tanks are not designed for such limited use. That leaves POU suppliers with two alternatives. They can live with the overkill and overpricing, or develop proprietary small-scale alternatives. To do the latter requires great commitment, not only in terms of research and development effort and dollars, but also in the volume commitment necessary to make the fruits of that effort economically feasible. As one famous television ad phrased the dilemma, "You can pay me now, or pay me later!"

Technology
Once the commitment has been made to POU ozonation, there remain all of the classic constraints on POU disinfection. Most notably, despite ozone's relative celerity among disinfecting agents, all chemical disinfectants require time to kill. While various recommendations have been made, and there is an obvious correlation between the dose administered and the time required, there appears to be a growing call for four minutes or more of ozone exposure time, based upon an assumed 0.4 mg/1 residual ozone. While only 20 percent of the typical chlorine or iodine protocol, four minutes is still 1,000 percent or more of the average water resident time within a typical POU counter-top or under-the-sink configuration (since, with the exception of RO systems, most POU systems utilize an "in-and-out" approach).

Unlike chlorine, which is relatively stable in water, ozone dissipates rapidly. Some combination of the ozone source and the holding tank must be designed to assure the continued presence of the residual for these four minutes. Most critical of all, there must be some form of holding tank which will stand up to this corrosive agent. The traditional "pass-through" POU system has proven less effective for iodine and chlorine than those which store water with the residual in place. The fact that ozone works faster than these alternatives is no reason to forsake the obvious conclusion that a pass-through is not enough.

Ozone at this scale also requires some form of air pump to infuse the gas into the water. This requires an electrical supply, as well as space not merely for the pump, but for venting. Abating the noise and vibration of the pump is critical to the successful marketing of such a system. In addition, ozone presents its own taste and odor challenges, similar to some traditional disinfecting agents. Activated carbon is simple and quite effective at abating ozone taste and odor. It is also necessary to eliminate many of the organic compounds subject to oxidation.

Finding a POU solution utilizing the carbon is not equally simple. To take advantage of line pressure to force water through GAC means eliminating the holding tank paradigm. To use a pump means adding cost, noise and vibration, as well as taking up space. That leaves manufacturers with an inappropriate first alternative, an expensive and unattractive second alternative, or the cheaper, hassle-free, but too often impractical alternative of a gravity-feed carbon filter.

Ozone also presents the unique quandary of undesirable fumes. While a typical ozone system is unlikely, albeit not incapable, of producing unhealthy levels of excess ozone, the fragrance of even small volumes leaves quite a lot to be desired. Therefore, a catalytic air filter, capable of ensuring rapid ozone degradation into oxygen, is a helpful add-on.

Current offerings
Thankfully, the challenges of price and science have not, at least thus far, doomed ozone to the spate of ineffective market offerings that polluted the iodinated resin market when similar obstacles were encountered. Iodinated resin once appeared to be "in vogue", promising the "miracle" of "space age" iodine technology. Large numbers of minimally effective and even unsafe products were offered alongside several highly efficacious and safe systems, which are still on the market today. Iodinated resin is not only a legitimate disinfection alternative, but an exceptionally effective and economical one, when coupled with the right system design. The problem stemmed not from the resin, but from charlatans who ignored the issues of time-dose response, residual kill time, and iodine removal.

To date, there have appeared no such blatant phonies among the few POU ozone systems that have found their way to market. In sharp contrast, what we see instead is a paucity of the number of systems available. Whether that is simply a function of timing, a result of the higher ozone market entry barriers, or a beneficial result of the lessons learned from the iodine experience, only time will tell. For the moment, however, the greater challenge facing POU ozone purchasers is price, not efficacy.

Ozone will no doubt continue to grow in popularity, at least until the next series of water treatment challenges are identified. The number of product offerings within any field of technology will always correlate to demand. When bacteria was the problem, more and more chlorine systems were introduced. When purification rather than disinfection was needed, RO and distillation systems abounded. When chlorine and THMs became bad words, iodine systems emerged. So too, with ozone a recognized cure for what the market currently believes ails it, look for a growing number of POU ozone systems over the coming months and years.

About the Author:
Steven G. Singer is Chairman of SemperPure Systems, Inc., master distributors for Pure 1 Systems of Billerica, Mass. A graduate of the Harvard Law School and summa cum laude graduate of the University of Pennsylvania, Singer spent over six years in the health care industry before joining SemperPure. Most recently, he served as COO of a NYSE listed conglomerate. Singer is a member of the WC&P; Technical Review Committee. He can be reached at (914) 235-8880 or (914) 235-8849 (fax).
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Article #7:
Mandatory Certification. An Opinion.
The home and office water treatment industry is largely unregulated, either by the government or internally. No other profession in the world allows anybody, regardless of his or her training, experience, or expertise, to, in effect, "prescribe" health-oriented products; products that, themselves, may have been manufactured with anywhere from excellent to poor quality control. While not often articulated as such, water is, universally, the single most important product that we consume in respect to our health and welfare. The quality of our water, more than any other product-including the air we breathe&emdash;defines how "well" or how "ill" we will be. With so much at stake, caveat emptor (buyer beware) should not and must not become our credo.

Governmental regulation of the home and office water treatment industry is both impractical and undesirable. Impractical because water quality is the quintessential multi-jurisdictional issue. Unless world-wide standards are agreed upon by all governments, an outcome that has eluded negotiators for time immemorial and across a broad range of issues (human rights, air quality, nuclear proliferation), quacks and charlatans will continue to peddle nefarious wares, albeit NIMBY ("Not In My Back Yard"). Governmental regulation is also notorious for complicating the simple, delaying the availability of urgently needed goods, and favoring those products and technologies that are presented by those most financially able to lobby and influence; not those which are objectively the best.

Trade associations such as the Water Quality Association, the International Bottled Water Association and others strive philosophically to achieve the goal of self-regulation, and we applaud these efforts. However, these organizations are forced by the balance of their goals to offer generally universal membership; that is, the intelligent and fastidious technician and the brazen fraud cannot be distinguished merely by their membership credentials. Special designations offered by trade groups, such as WQA"s Water Quality Specialist accreditation, are valuable voluntary programs for distinguishing on the basis of technical know-how, but not on the basis of ethics. Accreditation can help distinguish the enlightened from the uninformed, but can do nothing to distinguish the learned sinner from the learned saint.

The water industry should instead emulate, and indeed improve upon, the efforts of many in the medical device industry, where regulation and quality control derive from three distinct directions: First, the industry (or, preferably, its subsets) must establish industry-wide standards for product quality and safety; next, manufacturers must impose stringent quality standards upon themselves (preferably through volunteering to be scrutinized by independent members of the medical and scientific communities); and, finally, dealers must reward the manufacturers who do so by inquiring into (and becoming satisfied with) the quality control process that went into the products that they carry. Moves are underway in some corners to create just this offer. For example, in the growing market for iodine-based disinfection systems, two major and exciting developments are underway that could change the face of the water treatment industry, if followed by the rest of the industry. Tom Saunders of The Matrix Group, considered by many to be one of the founding fathers of iodine treatment, is well into the process of establishing an industry-wide advisory board, to set efficacy standards and to more fully understand the heretofore nebulous properties of iodine and its derivatives. That Saunders is driving this effort is significant in that he is one of the few players in this market who can gain nothing from the scrutiny of the experts he now seeks; in this industry segment, he himself is already an expert. Therefore, his effort must be viewed as selfless and genuine.

Of equal significance is the informal alliance recently formed by Pure 1 Systems and the Purolite C Company, which has established an independent technical advisory board. This Board brings together independent, highly reputable Endocrinologists, Oncologists, Chemists and Micro-biologists, to study and improve their products, with the mandate authority to ensure efficacy and safety, and to reject any product that fails to do so. What makes this group remarkable - beyond its very existence - is its diversity, the extraordinary credentials that its members bear, and the fact that no Board member is permitted to earn a substantial portion of his or her income from any or all of the Board's constituents. These are not the degreed mercenaries that are often recruited to fill such boards. Instead, we find among their ranks Harvard and Tufts Medical School instructors, Veterans Administration Endocrine Section Chiefs, and chemists and pharmacists recruited from reputable pharmaceutical firms.

The author believes that these models can and should be followed industry-wide. Iodine is not unique in the issues that its use presents. Bromine, Chlorine and Ozone, all halogens like iodine, present the same efficacy challenges, and far worse concerns regarding carcinogenic derivatives. Other products such as those employing distillation and RO, while perhaps of a simpler science, each must itself be assured to work efficaciously and, of equal importance, to guard against the ubiquitous risk of post-treatment recontamination. Sub-micron filters must genuinely work to specification, and even if they do, offer a bona fide cleansing and disinfection regimen -- not just the "no problem" attitude of years past. Bottled waters are, thank goodness, losing their longstanding and seemingly unrebuttable presumption of quality and purity, in favor of consumer questions about water origin and handling. All of these issues are better resolved by independent experts, and not by salaried employees of a company who, at best, suffer from a conflict of interest.

The entire industry suffers when even a single sub-standard product is granted market acceptance. Therefore, every reputable supplier that cares about and believes in the quality of its goods, should not just welcome but indeed actively solicit expert scrutiny. If this standard is ever attained, then only the quick-buck artists will be unable to provide independent verification of their product claims. Then we will at least all know which products not to buy.

Steven G. Singer New Rochelle, N.Y.


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