Today’s inquiry comes to us all the way from the United Kingdom. ‘Okello’ has interest in acquiring DPD test reagents for sanitizer/disinfectant level testing in water and asked, “I want the Quotation for DPD1-4″

At this time we carry 100 packs of DPD-1, DPD-3 and DPD-4 in the Water Testing Blog Test Kit Store.

Differences between DPD-1, 3 and 4?

For the answer to that question, we suggest that you take a look back at one of our earlier postings called What is DPD?. Not to brag, but we think that article does a decent job of answering the question.

To sum things up, though, below you will find the most common uses for DPD-1, DPD-3 and DPD-4:

• DPD-1 — Used by itself in a water sample to determine the free chlorine concentration in the sample.

• DPD-3 — Used after DPD-1 in a water sample to determine the sample’s total chlorine concentration.

• DPD-4 — Used by itself in a water sample to determine the total chlorine concentration in the sample.

So, before purchasing DPD, you may want to verify the type of chlorine testing that you will need to do — else run the risk of accidentally purchasing the incorrect DPD reagent(s)!

Where to purchase DPD?

As we stated earlier, you can purchase 100-packs of DPD-1, DPD-3 and DPD-4 from our Water Test Kit Store.

As for where to find other forms of DPD reagents, at this time we know of places to purchase two other forms of DPD: tablets and powder.

Need a new meter to test chlorine levels, too? We suggest looking at the eXact Chlorine Photometer available on the FilterWater.Com web site. It offers the reliability of DPD-based chlorine testing and the convenience of not having to match colors against a color chart.

Want accurate chlorine test results but don’t want to deal with DPD reagents and meters? Take a look at the SenSafe Free Chlorine water Check product currently available in our Water Test Kit Store. It bears USEPA Approval for use in municipal water testing and offers superior resistance to monochloramine interference that can sometimes affect the results obtained when testing for free chlorine residual using DPD test reagents.

Recently we got asked who should consider installing a commercial water filter. The person who asked the question, Sylvan, owns for a restaurant whose tap water routinely tastes and smells like bleach water. Needless to say ice from their ice maker has a hideous taste and smell.

For the past few years Sylvan lugged 5 gallon bottles of water around and paid a ton of money each week just so that his customers didn’t have to eat food cooked in chlorine and drink water that he currently refers to as ‘pool water’.

Sylvan had his water tested by a local lab and also tested it himself (using SenSafe Free Chlorine & SenSafe Total Chlorine) and the results always showed that his water contained far less free and total chlorine than the MCL (Maximum Contaminant Level) set by the USEPA — but that certainly did nothing about the stench of chlorine in his water.

In a case like this where a whole KITCHEN in a restaurant needs better quality water we believe devices like inline filters for ice makers and undersink water filters will not get the job done.

For applications where multiple unwanted water contaminants need to get removed on a larger scale (i.e. for a restaurant’s kitchen), commercial water filters stand out as ideal filtration options.

Other places where commercial water filters make the most sense include large private residences (over 4000 sq.feet), businesses, manufacturing facilities, apartment buildings, retail establishments, and schools.

Simply put, the total chlorine concentration in a water sample includes all available free chlorine plus all the chlorine that has already oxidized (acted on) contaminants in the water and become combined chlorine (monochloramines).

Free (available) chlorine refers to the concentration of chlorine molecules residing a water sample that have not, yet, oxidized contaminants. As a general rule you want to maintain a free chlorine residual in a body of water or water source.

Therefore, if a water sample has a total chlorine residual but no free, available chlorine, then the sample may or may not be ‘safe’. Some public (municipal) drinking water systems use only combined chlorine

Why would they do that?

It seems counter-intuitive that a public water systems would choose combined chlorine over free chlorine given free chlorine’s superior disinfecting (oxidizing) properties, but monochloramines do still have oxidizing capabilities and they do not create compounds (disinfection by-products, tri-halomethames, TTHM’s, etc.) that may cause cancer.

So… if you want to know how much free chlorine you have versus how much combined chlorine you have, simply subtract the free chlorine concentration from the total chlorine concentration:

(Total Chlorine) – (Free Chlorine) = Combined Chlorine

For pool water you can use a test strip like the Pool Check 5-Way or a Basic Taylor Test Kit to determine the free and total chlorine concentrations of a sample.

For drinking water you can use test strips like SenSafe Free Chlorine Water Check to determine the free chlorine concentration of a water sample and SenSafe Total Chlorine Water Check to determine the total chlorine concentration of a water sample.

OR, for an even easier test procedure, you can use the WaterWorks 2 Free & Total Chlorine Test Strip which tests for both free and total chlorine at the same time.

When opening a swimming pool too many people forget to TEST THE WATER before adding chemicals… Whether you choose to test the water yourself w/ test kits like the eXact Micro 7+ Pool Testing Meter or Pool Check Test Strips, or visit your local pool supply store and have them test your water at the beginning of the season, you will want to test for all or as many of these water quality parameters as possible. Note:

• Alkalinity – Not having the correct amount of alkalinity in your water will make getting and keeping the pH of your pool water very difficult.

• Calcium Hardness – Having too much calcium in your water could result in deposits forming and could also make it harder for other chemicals to dissolve in the water. Too little calcium in the water could result in pool water becoming aggressive and starting to attack various pool surfaces.

• Chlorine (Free) – If you use chlorine as your sanitizer, check to see if you have any left over from last year… or risk adding more than you need to add at the beginning of the year and ‘wasting’ money.

• Chlorine (Total) – If you use chlorine as your sanitizer and shocked your pool at the end of the previous season (as you SHOULD have), then you may have a lot of combined chlorine in your water that needs to get ‘burned out’ w/ a non-chlorine shock. Combined chlorine does little good when it comes to keeping pool water clean.

• pH – Incorrect pH levels drastically reduce the effectiveness of important pool chemicals such as bromine, chlorine, clarifiers, algaecides, etc.

• Metals – Having unwanted metals such as copper and iron in your pool water when you shock it w/ an oxidizer like chlorine or bromine at the beginning of the season could cause the metals to precipitate out of solution and stain pool surfaces.

• Stabilizer – Also known as cyanuric acid, having too little of this compound in pool water makes it difficult to maintain a free chlorine residual. Having too much of it can keep chlorine in a pool from doing its job.

• Total Dissolved Solids – Too many total dissolved solids in pool water will result in the water not accepting additional material… such as the chlorine powder (granules), tablets, sticks, or pool chemistry balancing chemicals.

So, get your water tested before adding start-up chemicals. Any questions?

Today’s inquiry came to us from ‘Kishore’ who asked a question about a liquid test reagent that turned yellow when added to a sample of water containing chlorine-based water disinfection tablets.

Dear Sir, I mixed chlorine tablets(water purification Tablets) in water. my friend taken water in Test tube. mixed one drop of liquid then water color changed in yellow. what is name of that liquid. how to by that.please can sent details.

Hello, Kishore, and thank you for the inquiry about a liquid test reagent that turns yellow in the presence of chlorine. Based upon your description we suspect your friend used a chemical called ‘OTO’ to perform the testing. OTO stands for Orthotolidine dihydrochloride. It test for total chlorine (free chlorine plus combined chlorine collectively).

You can find OTO in most pool supply stores, as it normally comes in the more basic pool water testing kits for total chlorine and pH, the two most commonly tested pool water quality parameters.

Many companies also sell the two reagents separately since they do tend to ‘go bad’ after a year once opened and exposed to air.

If you want to perform more precise chlorine concentration testing for free chlorine, the compound most people have the most interest in (usually) when attempting to determine if water has had the proper amount of disinfectant added to it, you will want to invest in a drinking water test kit that uses DPD-based reagents. ( What is DPD? )

For an even simpler means of testing the chlorine levels in water samples you may want to consider a product such as the SenSafe Free Chlorine Water Check, an EPA Approved method for determining free chlorine concentrations in drinking water, or the WaterWorks 2 Free & Total Chlorine product that uses the same free chlorine testing method as the SenSafe Free Chlorine Water Check and also includes a separate test area for total chlorine.

Want to know more about the differences between free and total chlorine? Check out an article called Free Chlorine, Combined Chlorine, Total Chlorine.

One more thing about OTO before we go: We have heard that some countries have outlawed its use due to scientists having evidence that it may cause cancer in humans… so check local laws before making a purchase!

We hope this helps!

Anyone that has taken the initiative to install a water filter or water purification device/system in their home deserves a bit of praise… and those that continue to take an interest in the quality of their water after installing a water treatment system deserve even MORE for their efforts.

As an example, ‘J. Mampilly’ from India installed a system and now seeks to determine if he has installed the correct unit. He asked,

I would like to know about how i can confirm the effectiveness of my water purifier. Labs in India that can certify and throw light on the camparative quality of water before and after using a water purifier. Thank You

Unfortunately we do not have familiarity with water testing laboratories in India and cannot directly assist with this situation. We can suggest, however, that you contact your local health department and ask them for a list of certified water testing laboratories in your area.

Coliform Bacteria Test Kit

Before…

In order to know what type of filter or what filtering capabilities you should purchase, invest (yes, we said invest) in a thorough water analysis performed by a qualified water testing laboratory. Here, again, we suggest contacting your local board of health and asking them, for a list of certified drinking water testing labs. Alternatively, or if no labs exist in your immediate vicinity, you can use the services of accredited water testing companies such as National Testing Labs.

No matter what, though, always have your water tested BEFORE deciding on a water treatment system. Oh, and one more thing: Don’t think for one second that a salesperson doing an in-home water test has the same water testing tools or qualifications as a reputable water testing laboratory. Remember: 99% of all salespeople attempt to sell things and not accurately analyze a situation — especially if accurately diagnosing a situation could cost them a sale!

And after!

As ‘J. Mampilly’ has done, we should ALL take an interest in comparing the quality of water that comes out of our water filter systems. Only then will we know if the money we invested in (not spent on!) a quality drinking water filter system performs as expected.

Testing water quality beforehand gives us not only an idea of what we need to filter out of our water, but also a checklist of water quality parameters to monitor post-filtration. Should follow up water testing reveal that these ‘issues’ did not get corrected or suddenly show up months after the installation of a water system, perhaps the water filter has stopped working or never really worked properly in the first place and needs service of some sort.

And in conclusion…

Many people go through life ‘deaf, dumb and blind’ when it comes to the quality of their water — until an (initially) unexplainable health problem pops into their life. Then, and unfortunately sometimes too late, those same people get very interested in the quality of their water and want to punish or otherwise penalize others for allowing them to consume tainted, polluted and/or contaminated drinking water.

Although we feel much sympathy for the victims of poor quality drinking water, most of us here in the United States have the ability to at least once every great while perform basic testing for critical water quality parameters such as heavy metals (i.e. lead, mercury, copper, iron, etc.), coliform bacteria, pesticides (i.e. atrazine and simazine), chlorine levels (free and/or total), total hardness, total dissolved solids, and many others.

Many times the contaminants in a water supply will have no taste, carry no odor and not appear before the naked eye. Only testing will alert you to their presence.

Every so often we receive questions from readers who ask something along the lines of, “What do most people ask about?”

Seemed odd at first (several years ago), but after getting asked the same thing so many times we eventually came to the conclusion that a good number of people really and truly don’t know what questions they ought to have about the quality of their drinking water.

Therefore, for your reading pleasure we will now give a list of the 10 most popular topics on Water Testing Blog for the month of August (2011):

1. Free Chlorine, Total Chlorine and Combined Chlorine
    
2. Testing for Fluoride in Water
    
3. Converting Hardness: Grains per Gallon to Parts per Million
    
4. What is DPD?
    
5. Chlorine Testing: Drinking Water vs. Pool Water
    
6. Simple Chlorine Testing Meter
    
7. Dirty Pool Water Can Make You Very Sick
    
8. Testing for Chlorine in Drinking Water
    
9. Lead in Soil
    
10. Private Well Water and Natural Gas Drilling

In no way does the above list begin to scratch the surface of what curious folks read on our site, but it may help you decide what questions YOU want answered… and if you come up with a question or topic you’d like us to address, send it to us using our submit a comment/question form.

It did, however, kind of shock us that hydraulic fracturing (aka: fracking), a means of extracting natural gas from shale buried deep beneath the Earth’s surface, came in so low on the list given the amount of (bad) publicity hydraulic fracturing has received in the past few years.

We also found it somewhat odd that bacteria in water did not make a single appearance in the list but then again, most folks in the United States have city/municipal water and make the assumption that city/municipal water couldn’t ever contain something as common as bacteria — and that, friends, can sometimes become a dangerous assumption to make!

Today’s question comes from ‘Mohamed’ who asked, “How much should be the free chlorine in the irrigation water? We are treating sewage water and sending it to farm lands. What is the international standard of the irrigation water in respect to free chlorine?”

We do not know of an International Standard for free chlorine levels in irrigation water but we do know that most States in the US require wastewater treatment plants to neutralize TOTAL chlorine levels before discharging water into the environment and that wastewater treatment facilities must test for total chlorine residuals in their effluent streams on a regular basis to make sure the chlorine concentrations stay virtually non-existent.

Why worry about chlorine in the environment?

If allowed to enter the environment chlorine can and will effectively kill or damage biological organisms that it comes in contact with. In great enough concentrations chlorine will wipe out all plant life in a body of water as well as any animals or fish in the water.

We use chlorine to render safe (i.e. KILL) biological contaminants in our drinking water and if released into a natural habitat the chlorine will render safe (i.e. KILL) any and all plant an animal life until it loses its effectiveness.

Testing for free & total chlorine?

Whether you prefer test strips, wet chemistry kits or a water testing meter… you have plenty of choices when it comes to testing for both free and total chlorine levels in drinking and treated waste water.

Do not let a clever sales pitch or catchy marketing jingle fool you. Many common drinking water filter systems do NOTHING to remove or reduce chloramines in water. They simply lack the technology in their filtration media to do so.

We mentioned this filter (the Pentek ChlorPlus) in the past and now feel the need to mention it again since we continue to receive inquiries from people asking why their water filters fail to remove all of the chlorine smell from their water.

The majority of water filters readily available in the marketplace do NOT remove chloramines, also known as combined chlorine. Most carbon filters remove free chlorine only. It takes a specialized type of filter like the Pentek ChlorPlus to cleanse water of unwanted chloramines.

Does my water contain chloramines?

Whether your municipal water system uses free chlorine or chloramines as its primary sanitizing agent we cannot say, but in either case your water will certainly contain chloramines. Unsure why? Take a look at this brief tutorial on free chlorine, total chlorine and combined chlorine.

That’s just a cartridge… What sort of housing does it go in?

A very keen observation followed by a very good question! The Pentek ChlorPlus filter for chloramine removal fits in most standard sized 10″ (by 2.5″) filter housings including, but not limited to, models manufactured by companies like Pentek, Ametek, US Filter, Bruner, American Plumber, Cuno, Filterite, Keystone, Water Resources and most Harmsco filter housings.

As always before purchasing a replacement cartridge for your water filter system, check, double check and TRIPLE check to make sure your housing will accommodate the filter cartridge you wish to buy!

While we do like to hear that the legal system has taken an interest in prosecuting those who threaten the safety and potability of water supplies, public or private, through acts of negligence or on purpose, it still bothers us that people would actually do things on purpose that could put the water supply of others at risk.

Today we stumbled across an article from a Chicago area paper talking about how a Federal Judge must decide whether or not a water company and also two of its employees should face charges for allegedly raising free chlorine levels intentionally right before taking readings and then allowing them to drop to potentially unsafe levels at other times throughout the day.

In the spirit of allowing both sides to present their case, we will post the entire article… which left us with more than one nagging question.

Our first question…

… deals with the frequency of testing: “Why did the plant only need to test in the mornings?”

Our second questions deals with the real results of the raising chlorine levels (supposedly) to pass inspection and then lowering them to potentially unsafe levels: “Did anyone get sick or suffer any form of harm as a result of these actions?”

Don’t get us wrong based upon that second question. We just want to know more about how these folks got caught. If someone got sick as a result of what the water company did, then this case would have ended in a guilty verdict without the need for the judge to deliberate longer… right?

Bitter truth about public water systems?

While few people would argue that the United States of America, when examined as a whole, has one of the most technologically advanced network of public water distribution systems in the world. This does not, however, mean that all of the systems do all of the testing they should at all the right times.

The article above, as well as articles we’ve read over the years about public officials and private firms fabricating water test results in an effort to save money, makes us leery of our great system… yet grateful as heck that for the most part our greatest fears about our public water supply deal mostly with ‘minor’ breaches in protocol rather than instances of blatant disregard for the maintaining of sanitary practices in our water treatment facilities.

Testing for chlorine in drinking water at home?

Do average people have the ability to keep tabs on the amount of chlorine in their drinking water? Absolutely! Companies like WaterSafe and SenSafe make reliable, accurate and completely affordable test kits for detecting levels of both free and total chlorine in tap/drinking water.