SWIMMING POOL DISINFECTION - Full Service Pool Care · 2018. 5. 15. · SWIMMING POOL DISINFECTION...
Transcript of SWIMMING POOL DISINFECTION - Full Service Pool Care · 2018. 5. 15. · SWIMMING POOL DISINFECTION...
SWIMMING POOL DISINFECTIONAn Evaluation of the Efficacy of Copper:Silver Ions
Excerpts from the University ofArizona Department ofMicrobiologyand ImmunologyLabReports.
8Metals for use in disinfection havebeen documented for many years,although they have only been in useas electrolytic devices in the UnitedStates since the early 193O's.8
8Free-chlorine concentrations can beaffected by sunlight, temperature,organic materials and the chemicalconsistency of the water. Organicmaterial may be introduced intoswimming pools by rain drainage, soil,foliage and animals. Swimmers canalso contribute large amounts oforganic matter to pool water in theform of sweat and urine. Active
. swimmers can perspire up to 1LJhandthe average swimmer can contribute25-50 mL of urine. All of these factorshave a chlorine demand and act tolower the levels of free chlorine in thewater. This poses one drawback to theuse of chlorine as a swimming-pooldisinfectant. Other negative aspectsInclude eye and skin imtation, lowresidual effect and the formation oftrihalomethane compounds which canbe absorbed through the skin orvolatilized and inhaled. For thesereasons, alternative disinfectantsystems have been investigated.8
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A letter quoted from Dr. CharlesGarba University of Arizona:
8During our experiments we paidparticular attention to the efficacy ofcopper:silver ions against J.agiooejlapneumopblla. Our experiments haveproven that copper:silver ionscombined with very low levels ofchlorine produces a synergistic effectwhich enables the dual disinfectants tokill ~ bacteria much morerapidlyand is up to 1000 times moreeffective than chlorine alone.8
8The additional benefit of thecopper:silver system is that there isalways a disinfectant in circulation thatis unaffected by sunlight andtemperature and, in fact, thebactericidal effect is enhanced bysunlight and high temperatures.8
8J.agiooejlapneumopblla is resilient tohigh levels of chlorine and is a mostdifficult bacteria to eliminate, especiallywithin systems that are exposed tosunlight and temperature such ascooling towers and hot water lineswhere levels of chemical biocides aredifficult to maintain, and in most cases,non-existent due to dissipation. Thisbreakthrough in water purificationmeans that the combination nowproduces a far more effective constantdisinfectant against L.e.giQruillapneumopbHa and other chlorineresistant strains of bacteria. Thesesystems are automatic and are easilymonitored once they are installed.8
Journal of Environmental Health Volume 51, Number 5
Abstract - 8Electrolytically generatedcopper:silver ions were evaluated asan alternative disinfectant to highlevels of chlorination in swimmingpools. Pure cultures of Escherichia coliand Streptococcus faecalis wereindividually tested by Inoculatingautoclaved well water with and without0.20 mgIL free chlorine. Copper:silverions in combination with free chlorinereduced bacterial numbers morerapidly than chlorine or copper:silverions alone. Numbers of S. faecalis alsowere reduced more In the combinedsystem than In the system containingonly free chlorine when exposed for0.5 min. The addition of copper:silverions allowed concentrations of freechlorine to be reduced to 0.20 mgllwhile still being able to meet guidelinesfor commercial swimming pooldisinfectants.8
,81nthe United States, 95 percent ofwater disinfection is achieved usingchlorine.Chlorineroutinelyis addedtoswimming pools to achieveconcentrationsof 0.6 - 1.0 mgIL freeavailablechlorine.Noticeablechlorineodor usuallyoccurs at concentrationsgreater than 0.6 mg/L. Highconcentrationsalso may also causeirritations of the eyes, mucusmembranes and skin, creatingconsiderable discomfort for swimmers..
8 As alternative to chlorine compounds,electrolyticallygenerated copper andsilver ions have been introducedrecently as a relatively safe andodorless method for waterdisinfection. ·
8Both copper and silver are bactericidaland virucidal and copper has beenshown to be algicidal and possessfungicidal properties.8
81n experiments using standardprocedures, E. call numbers weremore effectively reduced by thecombination of copper:silver ions andfree chlorine than with free chlorinealone. In the copper:silver ions with thefree chlorine system, the numbers ofE. coli were reduced 3.5 log 10 in 0.5minutes. The system containing freechlorine alone inactivated E. colinumbers 2.8 log 10 in 0.5 minutes.8
8The levels of copper and silver to beused in swimming pools apparentlywould not pose any health risks.Standards for copper levels in drinkingwater were established more foraesthetics than for health concerns..
"The use of copper and silver with lowlevels of chlorine as a method ofcommercial swimming pooldisinfection, thus, should greatlyoutweigh the negative aspects of highlevel chlorination, such as eye and skinirritation.·
"The data obtained indicate that asystem of electrolytically generatedcopper:silverions with concurrentlowlevel of free chlorine in water appearsto havean enhancedeffectin reducingmicrobial numbers. This would allowthe level of chlorine currentlyrecommended for commercialswimming pools to be reduced. 8