And we thank YOU, Colina, and your boss for all your business!  Regarding the two products, both detect concentrations of free chlorine in water samples and as you know, the  SenSafe 481026 product detects up to 6ppm and the WaterWorks 480023 product detects up to 25ppm.

Dilution method

To use the strips you have, you will need to use a dilution method.  Below you will find two examples of how to properly dilute a sample and back calculate the free chlorine concentration.

NOTE:  Make sure you use distilled or other water known to possess a zero chlorine concentration for dilutions.

• 1 part distilled water + 1 part water sample ... Perform a test using a test strip ... If you get a reading on the strip that matches one in the strip's color chart range, multiply that reading by (2) two to get the actual concentration of chlorine in your water sample.
• 2 parts distilled water + 1 part water sample ... Perform a test using a test strip ... If you get a reading on the strip that matches one in the strip's color chart range, multiply that reading by (3) three to get the actual concentration of chlorine in your water sample.

As a general rule we always suggest having the proper tool for any testing job.  Therefore we carry WaterWorks & SenSafe brands of water test strips for chlorine testing with varying detection ranges:

• Ultra low, low, high, and ultra high range free & total chlorine testing products

SenSafe Free Chlorine Water Check Detects 0 - 6 ppm

SenSafe Total Chlorine Test Strips Detect 0 - 10ppm

WaterWorks 2 Free & Total Chlorine Test Strips

Below you will find a simplified list of instructions on how to properly disinfect a drinking water well using a template and nucleation assisted crystalization process.  Please keep in mind, though, that all wells have differences and no two well water situations are exactly alike.  So, if this list does not provide you with enough guidance, contact your local environmental department and they can usually provide you either with more detailed instructions on their web site or the names of reputable, licensed well water professionals in your area.

1. Pump water from the well before disinfecting allowing all sediment, debris and other visible 'junk' to flow out of the well.  Leaving that stuff in the well during the disinfection process diminishes the cleansing effect of the chlorine bleach.
2. Add unscented chlorine bleach (on other words, just plain old laundry bleach... which usually has around 5% chlorine and no added fragrances) to the well and test the water coming out of the well.  You will want to add enough bleach until testing shows 50 to 100 parts per million (ppm) of bleach in the water.  The chart below will give you an approximation of how much unscented laundry bleach you may need to use.

Depth of Well	3 in.	6 in.	9 in.	12 in.
50 feet	3 ounces	8 ounces	25 ounces	50 ounces
100 feet	6 ounces	20 ounces	50 ounces	100 ounces
150 feet	8 ounces	30 ounces	75 ounces	150 ounces

After adding the bleach make sure you route the well's discharge water (the water produced by the well when turned on) back into the well so that the chlorine bleach mixes thoroughly in the well.  Mixing should take place for at least 15 to 20 minutes.

3. Reconnect the well's output hose to its normal connection (the one leading to the house) and open all faucets in the house individually.  Once a strong chlorine odor appears, close the tap.  Do this for each tap in the house.
4. Allow the chlorinated water remain in the well and house lines for no less than 2 hours, and preferably longer if you can.  The longer the chlorine stays in the lines, the better the odds of a successful well disinfection.  Usually around 24 hours works well for this purpose, though some experts say letting the system stand as long as possible makes the most sense.
5. After waiting no less than 2 hours and hopefully closer to (or longer than) 24 hours, open all taps/faucets in the house and allow the well to pump all of the chlorinated water out.  This step is called flushing the system.  Once the smell of chlorine has gone away, close the taps and your well should be ready for use.
6. To confirm that the disinfection process has worked, you will want to test water from the well in about a week to see if the source of bacteria still exists down in the well.

Important Note:  The instructions above serve as a rough guide for how to disinfect a drinking water well.  Obviously all wells have idiosyncrasies that make them unique so if the above instructions fail to take your well water situation's specifics into account, definitely err on the side of caution and seek the assistance of a trained water well professional!

Testing for higher levels of chlorine

We believe the WaterWorks High Range Free Chlorine product works well for this application.  It requires no special testing supplies, reagents or complicated test procedures and detects up to 120 parts per million free chlorine.

Free chlorine versus total chlorine?

When disinfecting a water well, you will normally want to test for free chlorine since a 'stable' free chlorine residual typically means a water sample no longer contains a significant number of biological contaminants.

Thank you for the chlorine testing question, MK.  At this time we have a High Range Free Chlorine product (MPN 480022) with a high detection limit of 120ppm, an Ultra High Range Free Chlorine product (MPN 480024) with a high detection limit of 750ppm, and an Ultra High Range II Free Chlorine product (MPN 480124) with a high detection limit of 2,000ppm.

If you need to test for Total Chlorine, regrettably we do not have a product that detects 120ppm total chlorine.  We do, however, have a High Range Total Chlorine product (MPN 480033) that detects up to 80ppm.  With a 50-50 dilution of the sample and appropriate 2x multiplier for the result detected by this product you could probably make it work -- assuming the level of total chlorine did not exceed 160ppm.

If simply drained into the streets the water winds up in storm drains which lead sometimes lead to local waterways where the chlorine could cause serious harm to aquatic life.

Draining pool water into sanitary sewer systems — the same ones that handle waste water and toilet water — could cause those systems to get backed up since many do not have the ability to handle large volumes of water.

So… How should I dispose of pool water?

From what we have read, environmental experts and department of public works employees suggest allowing the pool water’s chlorine level to dissipate as much as possible before releasing water into the environment or storm water systems. Make sure to keep the pool water circulating with the pool’s pump/filter during the dissipation process since doing so should aid in making the chlorine dissipation process go a little faster.

How will I know when the chlorine level drops close to zero?

Simple dip-and-read test strips for TOTAL chlorine, not free chlorine, work well and your basic 5-drop OTO pool water test kits work well, too.

Total Chlorine High Range
Test Strips

If you have a need to test for total chlorine levels (free chlorine + combined chlorine) in the range of 0 to 80 ppm then the Total Chlorine HR (High Range) water quality test strips will definitely come in handy. Sold in bottles of 50 tests, this product makes total chlorine testing in the field, in the lab, and just about anywhere a fast, easy process.

• Detection Range: 0, 5, 10, 20, 30, 40, 60, 80 ppm (mg/L)
• Total Test Time of Less Than 40 Seconds
• Manufacturer Part Number: 480033
• Made in the United States by Industrial Test Systems, Inc.
• Total Chlorine HR Test Strips require no powders to mix, tablets to crush, drops to add/count, or glass ampuoles to break.

What is the MCL (Maximum Contaminant Level) for Chlorine?

In municipal water systems the US Environmental Protection Agency has stated that a water treatment facility must take immediate action to reduce free and/or total chlorine levels in excess of 4 ppm (mg/L).

How Does the Total Chlorine HR Compare to DPD Test Methods?

Unlike DPD test methods for higher (than 10ppm) concentrations of total chlorine which require test personnel to perform dilutions before testing samples, the High Range Total Chlorine Test Strips allow for immediate, on-the-spot testing of water samples.

Why Do DPD Test Methods Require Dilution(s) of Samples?

When testing water samples containing more than 8 to 10 ppm of total chlorine either as free chlorine or combined chlorine the chemical indicator DPD ‘bleaches out’ and becomes clear. Therefore a sample must get diluted prior to testing to make certain the total chlorine concentration does not approach 8 parts per million.

The Total Chlorine High Range test procedure does not require dilution for samples containing more than 8 or 10 ppm chlorine since its chemical indicator can endure and continue to function properly in the presence of elevated chlorine levels.

Moral of the Story?

If you need to test for higher levels of total chlorine than traditional DPD methods allow, and you want to do it quickly and accurately, the WaterWorks Total Chlorine High Range test strip product will most certainly come in handy.

Hey, if the CDC (Centers for Disease Control) says millions of people each year in the United states alone get sick because of bacteria and other nasty contaminants on food, then we figure we ought to pay attention to the problem every once in a while.

How does one contract Listerosis?

The condition Listerosis (a serious infection) occurs when a person consumes food products contaminated with the bacterium Listeria monocytogenes.

Facts about Listerosis?

• An estimated 1,600 cases get reported each year; approximately 17% of them result in a fatality.
   
• Older adults, pregnant women, very young children, and those with compromised or suppressed immune systems stand the greatest chance of becoming infected.
   
• Note regarding pregnant women diagnosed with Listerosis: Infections during pregnancy may lead to miscarriage, stillbirth, premature delivery, and/or passing of the infection on to the the newborn child.
   
• Symptoms usually include fever, muscle aches, and gastrointestinal conditions including, but not limited to, diarrhea.
   
• More severe symptoms may include headache, confusion, and convulsions.
   
• The majority of patients diagnosed with Listerosis reported their illness to medical professionals only after the infection had already affected areas of the body beyond the gastrointestinal tract.
   
• Basic proper food handling, cooking, and storage methods serve as the absolute best means of keeping one safe from infection by Listerosis. Keep raw meats away from fresh fruits/vegetables, cook all meats thoroughly, and wash hands/utensils/countertops after encounters with uncooked or undercooked meats
   
• For additional information on Listerosis, such as a timeline of notable outbreaks in the United States, please take a look at the source article on the CNN web site

In a nutshell, basic food safety practices can drastically reduce one’s risk of infection. According to what we have read over the years, most cases of food poisoning did NOT have to happen and would not have happened if people had handled raw goods properly, kept raw goods away from other goods that would not get cooked, cooked meat products thoroughly and to the recommended internal temperatures, and stored raw or cooked goods properly.

Keeping one’s kitchen, cooking, food prep, and food service areas clean and clear of debris that could harbor potentially harmful bacteria, etc. also helps!

Products to test disinfecting and/or sanitizing solutions?

While at home most people would not usually test the strengths of cleaning solutions used to keep surfaces bacteria and germ-free, food production facilities and food service establishments DO have to test for things like chlorine, hydrogen peroxide, chlorine dioxide, ozone, iodine, quaternary ammonia, etc.

We all know that improperly balanced pool water can cause eye irritation due to a low/high pH, low/high alkalinity, and/or too high a chlorine count, but what about a properly balanced swimming pool? Does that water cause harm in any way?

According to the article,

• The human eye has a natural protective barrier over it that helps protect it from infection by bacteria, parasites, etc. Chlorinated water removes that thin layer temporarily.
   
• Swimming pools disinfected with chlorine may have the correct amount of chlorine in them to effectively ward off ‘bugs’, as the author called them, but that same chlorine loses some of its efficacy if the pH or alkalinity has drifted out of acceptable range.
   
• The amount of bacteria and other unwanted pool water contaminants introduced by a high bather load (aka: lots of people in the pool at one time) may temporarily overwhelm the chlorine concentration’s ability to neutralize threats to swimmers — especially their eyes whose protective tear layers have temporarily gotten washed away.
   
• Contact lens wearers may want to pay special attention to pool water water quality and possibly take extra steps to flush out their eyes after a swim. Putting lenses back in one’s eyes possibly without rinsing traces of pool water out first may allow infectious, or simply unwanted, bacteria and/or parasites to get trapped between a contact lens and a person’s eye… where it could breed, grow and basically cause problems.
   
• The good news? A properly sized and well-fitting set of goggles can really help minimize an eyeball’s exposure to tear film erasing chlorinated water and opportunistic ‘critters’ that sometimes lurk in pool water — like, for example (and we did not know this, by the way)… ‘pink eye’.

The article also mentioned something in passing: Carrying a pool water test kit with you to the pool. Sure you may look like a science geek or some sort of paranoid parent at the neighborhood pool, but if the water turns out to not possess the right chemicals to keep you and your family safe, well, we think a little embarrassment goes a long way!

Moral of the story?

Swimming pool water, even in the best circumstances, temporarily wipes away a vital protective barrier that our eyes rely upon to keep them ‘safe’. Therefore it stands to reason that we ought to make certain our pool water has the right balance of water chemistry (testing pool water helps with this!) and use properly fitting eye protection whenever we go for a swim!

Oh, and… one more thing before we go: At the beginning of each swimming season and each time a pool gets filled up or topped off with fresh water from a well or spigot, make sure to test the quality of the fill water for things like metals, hardness, alkalinity, pH, etc.

Why? Because just like in the world of computer programming, “Garbage in, garbage out!”

For your pool that means if you add water that has some water quality issues to begin with, then your pool water will have water quality issues, too.

Although both manufactured by Industrial Test Systems, Inc., a US based company in South Carolina, the DPD-1 ReagentStrip and SenSafe Free Chlorine Water Check products test for free chlorine residual in very different ways.

The chart below will explain the differences and similarities between the two free chlorine residual test methods:

	DPD-1 ReagentStrips™	SenSafe™ Free Chlorine Water Check
Detects:	Free Chlorine Residual (and Other Oxidizers Normally Tested Using DPD-1 Chemistry)	Free Chlorine Residual
Test Procedure Overview:	Liberarting of DPD-1 Reagents Off Reagent Pads Into 10mL Sample and Checking Chlorine Concentration Visually by Color Comparator or Electronically Using a Colorimeter	Immersion of Test Strip in Water Sample, Removal of Test Strip After Specified Period of Time, and Visual Comparison of Developed Color in Test Area to a Color Chart
Detection Range:	0-6ppm	0-6ppm
Accuracy & Precision:	Depends on the Method Used to Interpret the Developed Color in the 10mL Sample. Visual Methods Will Have Less Precision Than Meters	0, 0.05, 0.1, 0.2, 0.4, 0.6, 0.8, 1.2, 1.5, 2, 2.6, 4, 6 ppm (mg/L)
Certifications & Compliance:	DPD Testing as Specified in 4500-CL G Check w/ Your Local Health Department for Final Word on Compliance	USEPA Approved Test Method for Free Chlorine Read the EPA Letter   View EPA Approved methods   Check w/ Your Local Health Department for Final Word on Compliance
Number of Tests:	100 Tests per Package	50 Tests per Package
Benefits:	Cleaner to Use Than DPD-1 Powders (i.e. DPD-1 Powder Pillows)   Dissolves Easier Than DPD-1 Tablets   Longer Shelf-Life Than DPD Liquid Reagents   No Undissolved Solids When Testing in Cold Water (5ºC)   Requires No MSDS	Safe for Use on Most Production Floors   Requires No Specialized Testing Knowledge   No Expensive Meter (Colorimeter)   Designed to Resist Monochloramine Interference   Requires No MSDS
Per Unit Cost:	$15.99 per Package of 100 Tests	$15.99 per Bottle of 50 Tests

As always, if monitoring free chlorine residual for reporting and/or compliance monitoring we suggest contacting your local health inspector before switching to a different chlorine testing method.

Although seemingly counter-intuitive, many methods approved on a Federal level may not have attained acceptance, yet, on a State or Local level.

‘TomToo’ very recently — as in a few minutes ago — asked about chlorine testing and which chlorine test he should use:

“Saw your chlorine sale announcement and have a question. The water in our beach house stinks really bad of chlorine when we first get there and we want to test to make sure it’s safe to use but you have free and total chlorine strips. How do you know which to use?”

Thanks for your inquiry, TomToo, and believe us when we say others share your confusion when it comes to knowing which type of chlorine they need to test for.

Lucky for you, though, we have simple answer if your concern deals only with worrying about having too much chlorine in the water. You should test for total chlorine.

The USEPA set the Maximum Contaminant Level for chlorine in drinking water at 4 ppm (parts per million) and that number takes into account ALL of the chlorine in a water sample, meaning both free and combined chlorine.

Moral of the story?

If you need to know the FULL amount of chlorine in a drinking water sample, testing for total chlorine makes the most sense.

Whether testing drinking water at home, process water used in an industrial application, or wastewater for its chlorine before discharge into the environment, we feel quite certain that at least one of the chlorine test strip products above will come in handy — and this weekend you can save money when buying them!

As always, if you have any questions, please do not hesitate to ask! You may reach us easily using our Contact Us Form…. and yes we work on the weekends. 🙂

Have a great weekend, everyone, and don’t forget to stay hydrated!