Cleaning and Sanitising

Technical Bulletin_____________________________________________________________________

HTH* Dry Chlorinator for Use in:

CLEANING & SANITIZING Advantages of HTH∗Dry Chlorinator: HTH* Dry Chlorinator, which contains 68% available chlorine, is calcium hypochlorite, one of the most effective sanitizers known. It is convenient, easy to use and handle, doesn't require expensive, complex metering equipment or large storage tanks, and doesn't lose strength rapidly during storage. Be sure to comply with all government regulations for use.

CONTENTS GENERAL SANITIZATION PRACTICE _____1 Non-Porous Food Contact Surfaces_______________1 Rinse Method________________________________1 Immersion Method____________________________1 Flow/Pressure Method _________________________2 Clean-in-Place Method ________________________2 Spray/Fog Method ____________________________2 Non-Porous Non-Food Contact Surfaces __________2 Porous Surfaces -- Non-Food Contact_____________3 Porous Surfaces --Food Contact _________________3

MOLD & MILDEW REMOVAL ____________3 Preparation of Aqueous Solution for Mildew _______3 Stability ____________________________________3 Determination of pH __________________________4 Determination of Calcium Hypochlorite and Total Alkalinity ___________________________________4 Calculations ________ Error! Bookmark not defined.

RESTAURANT UTENSILS_________________5 LAUNDRY SANITIZERS __________________6 Household Laundry Sanitizers___________________6 Commercial Laundry Sanitizers _________________6

ASPHALT OR WOOD ROOFS AND SIDINGS 6 RELATED INFORMATION ________________6

among them is dictated by the shape and size of the surface requiring treatment.

Rinse Method A solution of 100 ppm available chlorine may be used in the sanitizing solution if a chlorine test kit is available.

Solutions containing an initial concentration of 100 ppm available chlorine must be tested and adjusted periodically to insure that the available chlorine does not drop below 50 ppm. Prepare a 100 ppm sanitizing solution by thoroughly mixing 15 grams of this product with 100 liters of water (1 oz./ 40 gallons). If no test kit is available, prepare a sanitizing solution by thoroughly mixing 15 grams of this product with 50 liters (1 oz./20 gallons) of water to provide approximately 200 ppm available chlorine by weight.

Clean equipment surfaces in the normal manner. Prior to use, rinse all surfaces thoroughly with the sanitizing solution, maintaining contact with the sanitizer for at least 2 minutes. If solution contains less than 50 ppm available chlorine, as determined by a suitable test kit, either discard the solution or add sufficient product to reestablish a 200 ppm residual. Do not rinse equipment with water after treatment and do not soak equipment overnight. Sanitizers used in automated systems may be used for general cleaning but may not be reused for sanitizing purposes.

GENERAL SANITIZATION PRACTICE

Immersion Method

Non-Porous Food Contact Surfaces The five methods described below may be used to sanitize non-porous food contact surfaces. The choice

A solution of 100 ppm available chlorine may be used in the sanitizing solution if a chlorine test kit is available.

Solutions containing an initial concentration of 100 ppm

 2000 Arch Chemicals *HTH is a registered trademark of Arch Chemicals, Inc. Arch Chemicals, Inc 501 Merritt 7, P.O. Box 5204, Norwalk, CT 06856-5204 USA

HTHADS00-6 1/00

available chlorine must be tested and adjusted periodically to insure that the available chlorine does not drop below 50 ppm. Prepare a 100 ppm sanitizing solution by thoroughly mixing 15 grams of this product with 100 liters of water (1 oz./ 40 gallons). If no test kit is available, prepare a sanitizing solution by thoroughly mixing 15 grams of this product with 50 liters (1 oz./20 gallons) of water to provide approximately 200 ppm available chlorine by weight.

Clean equipment in the normal manner. Prior to use, immerse equipment in the sanitizing solution for at least 2 minutes and allow the sanitizer to drain. If solution contains less than 50 ppm available chlorine, as determined by a suitable test kit, either discard the solution or add sufficient product to reestablish a 200 ppm residual. Do not rinse equipment with water after treatment.

Sanitizers used in automated systems may be used for general cleaning but may not be reused for sanitizing purposes.

Flow/Pressure Method Disassemble equipment and thoroughly clean after use.

Assemble equipment in operating position prior to use.

Prepare a volume of a 200 ppm available chlorine sanitizing solution equal to 110 % of volume capacity of the equipment by mixing the product in a ratio of 15 grams product with 50 liters of water (1 oz. product with 20 gallons of water. ) Pump solution through the system until full flow is obtained at all extremities, the system is completely filled with the sanitizer and all air is removed from the system. Close drain valves and hold under pressure for at least 2 minutes to insure contact with all internal surfaces. Remove some cleaning solution from drain valve and test with a chlorine test kit. Repeat entire cleaning/sanitizing process if effluent contains less than 50 ppm available chlorine.

Clean-in-Place Method Thoroughly clean equipment after use. Prepare a volume of a 200 ppm available chlorine sanitizing solution equal to 110 % of volume capacity of the equipment by mixing the product in a ratio of 15 grams product with 50 liters of water (1 oz. product with 20 gallons of water.) Pump solution through the system until full flow is obtained at all extremities, the system is completely filled with the sanitizer and all air is removed from the system. Close drain valves and hold under pressure for at least 10 minutes to insure contact with all internal surfaces.

Remove some cleaning solution from drain valve and test with a chlorine test kit. Repeat entire cleaning/ sanitizing process if effluent contains less than 50 ppm available chlorine.

Cleaning & Sanitizing

Spray/Fog Method Preclean all surfaces after use. Use a 200 ppm available chlorine solution to control bacteria, mold or fungi and a 600 ppm solution to control bacteriophage. Prepare a 200 ppm sanitizing solution of sufficient size by thoroughly mixing the product in a ratio of 30 grams of product with 100 liters of water. Prepare a 600 ppm solution by thoroughly mixing the product in a ratio of 90 grams product with 100 liters of water (3 oz. product with 20 gallons of water.) Use spray or fogging equipment which can resist hypochlorite solutions. Always empty and rinse spray/fog equipment with potable water after use.

Thoroughly spray or fog all surfaces until wet, allowing excess sanitizer to drain. Vacate area for at least 2 hours.

Prior to using equipment, rinse all surfaces treated with a 600 ppm solution with a 200 ppm solution.

Non-Porous Non-Food Contact Surfaces RINSE METHOD Prepare a sanitizing solution by thoroughly mixing 30 grams of HTH速 Dry Chlorinator with 100 liters of water to provide approximately 200 ppm available chlorine by weight. Clean equipment surfaces in the normal manner.

Prior to use, rinse all surfaces thoroughly with the sanitizing solution, maintaining contact with the sanitizer for at least 2 minutes. Do not rinse equipment with water after treatment and do not soak equipment overnight.

These surfaces may be disinfected by increasing the solution strength to 600 ppm available chlorine and increasing the contact time to 10 minutes. Once again, do not rinse with water and do not soak equipment overnight.

IMMERSION METHOD Prepare a sanitizing solution by thoroughly mixing, in a immersion tank, 30 grams of HTH Dry Chlorinator with 100 liters of water to provide approximately 200 ppm available chlorine by weight. Clean equipment in the normal manner. Prior to use, immerse equipment in the sanitizing solution for at least 2 minutes and allow the sanitizer to drain. Do not rinse equipment with water after treatment.

To disinfect with this method, increase solution strength to 600 ppm and increase contact time to 10 minutes or more. Do not rinse.

SPRAY/FOG METHOD - Preclean all surfaces after use. Prepare a 200 ppm available chlorine sanitizing solution of sufficient size by thoroughly mixing 30 grams HTH Dry Chlorinator with 100 liters of water. Use spray or fogging equipment which can resist hypochlorite solutions. Prior to using equipment, thoroughly spray or fog all surfaces until wet, allowing excess sanitizer to drain. Vacate area for at least 2 hours.

Page 2

Porous Surfaces -- Non-Food Contact RINSE METHOD - Prepare a sanitizing solution by thoroughly mixing 90 gramsof HTH Dry Chlorinator with 100 liters of water to provide approximately 600 ppm available chlorine by weight. Clean surfaces in the normal manner. Prior to use, rinse all surfaces thoroughly with the sanitizing solution, maintaining contact with the sanitizer for at least 2 minutes. Do not rinse equipment with water after treatment and do not soak equipment overnight.

IMMERSION METHOD - Prepare a sanitizing solution by thoroughly mixing, in an immersion tank, 90 grams HTH Dry Chlorinator with 100 liters of water to provide approximately 600 ppm available chlorine by weight.

Clean equipment in the normal manner. Prior to use, immerse equipment in the sanitizing solution for at least 2 minutes and allow the sanitizer to drain. Do not rinse equipment with water after treatment.

SPRAY/FOG METHOD - After cleaning, sanitize non-food contact surfaces with 600 ppm available chlorine by thoroughly mixing the product in a ratio of 90 grams of HTH Dry Chlorinator to 100 liters of water. Use spray or fogging equipment which can resist hypochlorite solutions. Always empty and rinse spray/fog equipment with potable water after use. Prior to using equipment, thoroughly spray or fog all surfaces until wet, allowing excess sanitizer to drain. Vacate area for at least 2 hours.

Porous Surfaces --Food Contact Each of the methods above may be improved to assure sanitization for food contact. After the 600 ppm treatments described above, rinse the equipment with a solution containing 200 ppm available chlorine prior to using the equipment. Do not rinse with water or soak overnight.

MOLD & MILDEW REMOVAL HTH Dry Chlorinator is effective in killing and removing mildew and fungi, and in preventing their growth. The following information is a reference guide to help prepare formulations containing HTH Dry Chlorinator for their control. All commercial sanitizers sold for biocidal applications must be registered with the Environmental Protection Agency (EPA). Arch Chemicals has produced HTH Dry Chlorinator for over 50 years and has obtained registration for many of these applications. Some of them are presented here, but if your specific needs are not included, contact your nearest Arch Chemicals sales office. Additional data are on file, or we may be able to help you obtain the necessary government registrations.

Cleaning & Sanitizing

Preparation of Aqueous Solution for Mildew To make up a 3.5% available chlorine solution, use the following for each 100 liters or gallons of water:

Ingredients Tap Water (liters) 

Quantity 100

HTH Dry Chlorinator, granular (kgs)

5.4

Caustic Solution, 50% (kgs)

0.38

Directions Add the required volume of tap water to the dissolving tank. With the exhaust fan operating, gradually add the proper amount of granular HTH Dry Chlorinator to the water, while agitating by means of a sparge line. (A corrosion resistant agitator shaft and blade may be used instead of a sparge line.)

Then add the required amount of caustic solution to the HTH chlorine solution, while agitating. Depending on the degree of agitation, continue to mix for one to two hours. After mixing, stop the agitation and let the small amount of insolubles settle to the bottom.

For the next step, you'll need a special test kit designed to measure available chlorine. (Arch Chemicals can recommend one appropriate for your application.) Test for available chlorine in the clear upper solution to see if all the HTH Dry Chlorinator is in solution. A low level of available chlorine may indicate the need for additional mixing. If necessary, repeat mixing.

Allow insolubles to settle out for four to six hours or overnight. Then pump the upper solution through the filter to the holding tank. While pumping, place the transfer line into the solution above the insolubles which are on the bottom of the dissolving tank.

Check the quality of the solution in the holding tank by determining the temperature, percent of available chlorine and the pH.

Stability The stability of solutions containing HTH Dry Chlorinator, in general, depends on five factors: •

Concentration of HTH Dry Chlorinator

•

Concentration of certain catalysts

•

Total alkalinity or pH value of the solution

•

Temperature of the solution

Page 3

•

Equations:

Exposure to sunlight

( Eq. 1)

Copper, nickel and cobalt are catalysts of decomposition.

Copper from brass, bronze or copper fittings, and nickel from stainless steel equipment may find their way into the solution. Cobalt, which has the least effect, is not likely to be encountered. If aluminum, copper, iron, nickel and other impurities are avoided while preparing the solution, decomposition will be minimized. Decomposition can also be retarded by controlling the alkalinity of the solution with excess caustic soda. (In strong hypochlorite solutions, it is customary to refer to "excess total alkalinity".)

Ca(OCl) 2 + 4 KI + 4 HCl → CaCl 2 + 4 KCl + 2 I 2 + 2 H2 O

(Eq. 2)

Ca(OH) 2 + 2 HCl → CaCl 2 + 2 H 2 O

(Eq. 3)

2I 2 + 4 Na 2S2 O 3 → 2 Na 2S 4 O 6 + 4 NaI

(Eq. 4)

HCl (Excess) + NaOH → NaCl + H 2 O

Reagents:

The quality of an HTH Dry Chlorinator solution depends greatly on its stability, which is enhanced under the following conditions:

•

Sodium thiosulfate (Na2S2O3), standard 0.1 N solution

•

Potassium iodide (KI), granular, neutral or A.C.S. reagent grade

•

Hydrochloric acid (HCl), standard 0.1 N solution

•

As little iron, copper and nickel as possible

•

Sodium hydroxide (NaOH), standard 0.1 N solution

•

Low concentrations of HTH Dry Chlorinator

•

Starch indicator, 0.5% solution

•

pH of about 12

•

Bromcresol green indicator, 0.1% solution

• •

Excess total alkalinity of 0.15% to 0.20% as NaOH Storage at low temperatures, in containers which are opaque to light, for maximum shelf life.

•

Glacial acetic acid (used for calcium hypochlorite testing only and not for total alkalinity)

Determination of pH The most practical method of determining the pH of HTH chlorine solutions is by using a glass electrode and pH meter. Use high-alkalinity electrodes for the measurement. The pH meter should be standardized before measuring the pH of the sample solution.

Commercial standard buffer solutions covering the various pH ranges may be used.

Procedures: Accurately weigh out a 3.5 gram sample of the solution and transfer to a 500 ml Erlenmeyer flask. Dilute with about 100 ml of distilled H2O. Add 2 grams KI crystals (neutral); mix, then add from a buret sufficient volume of standard 0.1 N HCl to provide an excess over that required by reaction equations 1 and 2 (50 ml is usually sufficient). Record the volume of acid used as "ml HCl".

Determination of Calcium Hypochlorite and Total Alkalinity

Immediately titrate the liberated iodine with standard 0.1 N Na2S2O3 adding 2 ml of starch indicator solution when most of the yellow iodine color has disappeared.

Carefully finish the titration until the blue starch-iodide color just disappears. Record the volume of solution used as “ml Thio A”.

Hypochlorite and total alkalinity are determined on the same sample by adding a measured excess of standard acid, titrating the hypochlorite with standard thiosulfate, and backtitrating the excess of acid with standard alkali.

Add 5 drops of bromcresol green indicator solution and titrate the excess HCl with standard 0.1 N NaOH to the end point when the color just turns from greenish-blue to blue. Record the volume of solution used as “ml NaOH”.

Calculations % Ca ( OCl ) 2 =

Cleaning & Sanitizing

ml Thio A x N x 3.5746 g of sample

Page 4

% Av. Cl. (as Cl 2 ) = % Total Alkalinity = as NaOH

ml Thio A × N × 3.5453 g of sample

(ml HCl × N) ≤ [(ml Thio A × N) + (ml NaOH × N)] × 4.0 g of sample

Figure 1 Schematic Flow Diagram for Preparing HTH Chlorine Solution

B

Equipment A. Dissolving Tank with Lid (polyethylene) B. Sparge Line (polyethylene or polyvinyl chloride) C. Filter (5 micron) D. Solution Holding Tank with Lid (polyethylene)

Analytical Notes: 1. If a pure blue color appears before the addition of sodium hydroxide solution, there is no excess acid to be titrated. The total alkalinity cannot be determined on this sample and the thiosulfate titration is probably low.

Discard the sample and the results. Weigh out a fresh sample and treat as before but use a larger volume (75 ml) of standard 0.1 N HCl solution.

Other:

Centrifugal Transfer Pumps (corrosion-resistant, plastic or lined) Plug Valves and Pipe (polyvinyl chloride)

2. If percent calcium hypochlorite only is desired, the use of standard HCl is unnecessary. Simply follow the addition of KI by the addition of 10 ml glacial acetic acid.

Then titrate the liberated iodine as described above.

Record the volume of standard thiosulfate used as "ml Thio A" and calculate % Ca(OCl)2 or % available chlorine as shown.

RESTAURANT UTENSILS Solutions of HTH Dry Chlorinator containing 100 ppm available chlorine will kill bacteria on dishes, glasses and other eating utensils.

Fresh HTH chlorine solutions should be prepared each morning and as frequently as necessary during the day.

Cold or warm water may be used. The solution should never be allowed to fall below 50 ppm available chlorine.

Cleaning & Sanitizing

Page 5

Commercial Laundry Sanitizers Small quantities of this solution can be prepared by adding 1 level teaspoon of HTH Dry Chlorinator to 20 liters or 5 gallons of water, or 1 level tablespoon of HTH Dry Chlorinator to 60 liters or 15 gallons of water. (Be sure to use a spoon that is completely dry and clean.)

Before treatment, clean all utensils thoroughly. Then immerse them in the HTH chlorine solution.

Wet fabrics or clothes should be spun dry prior to sanitization. Thoroughly mix 30 gramsof HTH Dry Chlorinator in 100 liters of water to yield 200 ppm available chlorine. Promptly after mixing the sanitizer, add the solution into the prewash prior to washing fabrics/clothes in the regular wash cycle with a good detergent. Test the level of available chlorine if solution has been allowed to stand. Add more of this product if the available chlorine level has dropped below 200 ppm.

LAUNDRY SANITIZERS Household Laundry Sanitizers IN SOAKING SUDS - Thoroughly mix 15 gm. of HTH Dry Chlorinator in 50 liters of wash water to provide 200 ppm available chlorine. Wait 5 minutes, then add soap or detergent. Immerse laundry for at least 11 minutes prior starting the wash/rinse cycle.

IN WASHING SUDS - Thoroughly mix 15 gm. of HTH Dry Chlorinator in 50 liters of wash water con-taining clothes to provide 200 ppm available chlorine. Wait 5 minutes, then add soap or detergent and start the wash/rinse cycle.

ASPHALT OR WOOD ROOFS AND SIDINGS To control fungus and mildew, first remove all physical soil by brushing and hosing with clean water, and apply a 5000 ppm available chlorine solution. Mix 75 grams of HTH Dry Chlorinator with 10 liters of water and brush or spray roof or siding. After 30 minutes, rinse by hosing with clean water.

RELATED INFORMATION HTH Dry Chlorinator -- Product Data Bulletin AD 6158-297

Please refer to the Material Safety Data Sheet (MSDS) for complete information on Storage and Handling, Toxicological Properties, Personal Protection, First Aid, Spill and Leak Procedures, and Waste Disposal. To order an MSDS, call your Arch Chemicals sales office. Review the MSDS thoroughly before handling product.

 2000 Arch Chemicals *HTH is a registered trademark of Arch Chemicals, Inc. Arch Chemicals, Inc 501 Merritt 7, P.O. Box 5204, Norwalk, CT 06856-5204 USA

HTHADS00-6 1/00

This bulletin and the information and statements contained in it are offered to the reader for its consideration. The reader relies on the statements made herein at its own risk, and should conduct its own independent investigation and verification of such statements and information, including without limitation statements regarding dosages and usage of the product described. Conditions at User's facility(ies) may vary and may require different usage or quantities. ARCH CHEMICALS, INC. MAKES NO REPRESENTATION OR WARRANTY HEREIN EXPRESS OR IMPLIED WITH RESPECT TO ANY PRODUCT OR ITS PROPER USE. ARCH DISCLAIMS ANY AND ALL WARRANTIES IMPLIED BY LAW OR ACTION, INCLUDING, WITHOUT LIMITATION WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE WITH RESPECT TO ANY PRODUCT OR ITS USE. SHOULD ARCH CHEMICALS, INC. BE FOUND RESPONSIBLE FOR ANY CLAIM WITH RESPECT TO A PRODUCT OR ITS USE, WHETHER SUCH CLAIM IS BASED ON NEGLIGENCE, CONTRACT OR OTHERWISE, ARCH CHEMICALS, INC.'S LIABILITY SHALL BE LIMITED TO THE SALES PRICE RECEIVED

BY ARCH FROM THE PARTY CLAIMING DAMAGES FOR THE PRODUCT WITH RESPECT TO WHICH DAMAGES ARE CLAIMED. FURTHER, ARCH CHEMICALS, INC. SHALL NOT BE RESPONSIBLE FOR ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT LIMITATION ANY CLAIM BY A THIRD PARTY AGAINST THE READER, IN CONNECTION WITH ANY PRODUCT OR ITS USE. The User of any product accepts full responsibility for compliance with all applicable federal, state and local laws and regulations. Nothing contained herein will be construed to constitute permission or a recommendation to use the product in any process or formulation covered by a patent or patent application owned by Arch Chemicals, Inc. or by others. No statements or representations which differ from the above shall be binding upon Arch Chemicals, Inc. unless contained in a duly executed written agreement.

 2000 Arch Chemicals *HTH is a registered trademark of Arch Chemicals, Inc. Arch Chemicals, Inc 501 Merritt 7, P.O. Box 5204, Norwalk, CT 06856-5204 USA

HTHADS00-6 1/00