No one in their right mind would argue that testing water for drinking, use in a pool, watering crops, etc. has to happen. One might, however, argue that using test strips and liquid test kits which require the user to match colors can lead to approximations and assumptions regarding critical water parameters such as pH, chlorine/bromine/sanitizer levels, alkalinity, total hardness, heavy metals, etc.

We all know what assumptions can lead to: Making an a## out of you and me.

No one wants to get sick from dirty or polluted water so when accuracy matters most, you may want to put down the test strips and liquid test kits and opt for a verstile water testing meter such as the eXact Micro 7+ which tests for NINE critical water parameters using direct read measurements and an additional TWENTY-SEVEN other important water parameters with the use of a conversion chart.

Features of the eXact Micro 7+ Water Testing Meter:

• Tests for 36 parameters in total

• Nine direct read parameters — Total Alkalinity, Bromine, Calcium Hardness, Free Chlorine, Total Chlorine, Copper, Ozone, Permanganate, and pH

• Twenty-Seven parameters using a conversion chart: Ammonia, Chloride (as NaCl), Chlorine Dioxide (DPD-1), Chromium Hexavalent, Cyanuric Acid, Fluoride, Hydrazine, Hydrogen Peroxide (Low, Mid and High Range), Iodine (DPD-1), Iron (Fe+2), Total Iron (Fe+2/Fe+3), LR Total Hardness (as CaCO3), Magnesium, Manganese, Nitrate (as NO3), Nitrite (as NO2), pH (Acid and Alkali), Potassium, Protein (as BSA), Sulfate, Sulfide, and Turbidity

• USEPA Compliant meter for Free & Total Chlorine — 0.01 ppm (mg/L) precision

• Built-in, permanent cell — no loose glass or plastic cells to lose

• Easy fill testing — Simply fill or dip meter into water

• Automatic countdown timer for accurate timing of testing

• 140 test memory — saves 20 tests per menu item

• Incorporates eXact® Strip technology — safe & reliable reagent dispersion

• No-slip grip housing — ideal for wet testing conditions

• Lightweight — weighs only 6 ounces w/ batteries installed

• Waterproof — IP-67 Rated and meter will float if dropped into water

• Easy-to-read LCD display — no color matching required

• Environmentally friendly — recyclable parts & uses 60% less reagents than 10mL sample tests

• Proprietary optics — allows for accurate testing without cap

• CE certification

Interested in learning how this device works? Check out the image below as it takes you through the steps of how to test w/ the eXact Micro 7+ Water Testing Meter.

Several members of the Water Testing Blog staff have spoken with members of the military, both currently enlisted and recently discharged, and found out that some soldiers do not have access to simple, efficient tools they can use to test potential drinking water while deployed in foreign countries.

In most cases they carry packets of sanitizing/disinfecting tablets which they can use to put into their canteens to kill off bacteria, but what about lead, arsenic, cyanide and other items which can EASILY render an entire unit inoperable and take them away from their assigned duties?

Thankfully US Army, Navy, Air Force, and Marine Corps medical units deployed around the globe now have the ability to make use of simple water quality test kits which give them the ability to read basic water quality parameters quickly and easily.

Arsenic in Water and Soil: Arsenic Quick^TM

Bacteria in Water: Bacteria Check

Chlorine Residual (Free): SenSafe^TM Free Chlorine Water Check

Chlorine Residual (Total): SenSafe^TM Total Chlorine Water Check

Cyanide in Water: Cyanide ReagentStrip^TM

DPD-1 and DPD-4 (Chlorine Testing): eXact DPD ReagentStrips^TM

Lead in Water: Lead in Water Test Kit

Multi Parameter (6 Parameters): Well Water Check

Multi Parameter (11 Parameters): Well Driller Standard Water Test Kit

Multi Parameter (13 Parameters): COMPLETE Water Test Kit

Multi Parameter (15 Parameters): Water Quality Test Kit

Most of us know how badly we feel after ‘a night on the town’ filled with margaritas, martinis, cocktails and body shots because of dehydration. Now try to imagine how our soldiers must feel after a few MONTHS in the desert wearing full combat gear.

Safe drinking water means safer soldiers.

One of the most widely used testing methods for free and total chlorine makes use of something known as ‘DPD’ which stands for N,N Diethyl-1,4 Phenylenediamine Sulfate. The addition of DPD to water samples containing oxidizers such as free chlorine, bromine, iodine, chlorine dioxide and/or permanganate results in the formation of a reddish tint to the water whose intensity directly relates to the amount of oxidizer(s) present in the water sample.

At low oxidizer concentrations water samples turn a slight shade of pink in the presence of DPD and at higher oxidizer concentrations the sample will turn blood-red orange. In extremely high concentrations of oxidizers, as in above 10 ppm, the sample will turn blood-red and then go crystal clear due to the bleaching effect of the oxidizer(s) it contains.

Other oxidizers such as ozone and total chlorine do not react directly with DPD and require the addition of a compound known as Potassium Iodide (KI) before they will react with DPD.

• DPD-1 — Used to test oxidizer levels in water samples containing free chlorine, bromine, iodine, chlorine dioxide and/or permanganate.
• DPD-3 — Useless on its own, but when added to samples already containing DPD-1 and free chlorine, total chlorine, bromine, iodine, chlorine dioxide, permanganate and/or ozone, pink through blood-red color development will occur in the sample.
• DPD-4 — The combination of DPD-1 (N,N Diethyl-1,4 Phenylenediamine Sulfate) and DPD-3 (KI) to samples containing free chlorine, total chlorine, bromine, iodine, chlorine dioxide, permanganate and/or ozone will result in pink through blood-red color development in the sample. Simply put, DPD-1 + DPD-3 = DPD-4.

DPD comes in various forms, the most common of which include tablets, powder pillows, liquids and ReagentStrips^TM. Each works equally well when used correctly and may typically be interchanged with one another, though all do have their pros and cons.

• Tablets: One of the cheapest forms of DPD available and has a very long shelf-life. Difficult to break apart and dissolve in cold or hard water samples and may leave suspended solids floating around in samples.
• Powder Pillows: Inexpensive form of DPD. Difficult to dissolve in cold or hard water samples and may leave suspended solids floating around in samples. Users also complain of ‘annoyance value’ associated with having to tear the foil pillows open and pour the DPD powder into the sample vials. Not well-suited for outdoor testing.
• Liquids: Shorter shelf-life and much more unstable than other forms of DPD, considered ‘messy’ by many users, but also probably the expensive form of DPD.
• ReagentStrips^TM: Convenient delivery method for DPD, rarely leaves undissolved solids in samples regardless of temperature or hardness, decent shelf-life, and available in bottles of 50 or individually wrapped tests (excellent for field work).

While many test protocols call only for a visual verification of chlorine levels in water determined through the use of DPD testing methods, many others require the use of a digital chlorine analyzer and DPD testing methods. Below please find an EPA Compliant meter which make use of DPD chemistry for chlorine concentration determination:

• eXact Micro 7+ Water Quality Testing Meter — EPA Compliant for free and total chlorine when used in conjunction with a DPD-based reagent system.  Handheld multi-parameter water quality testing meter.  IP67 waterproof rating and the unit floats. Made from recyclable parts and uses 60% less reagent than devices using 10 mL samples.

Update — Got a chlorine test kit/meter that has a 10 mL sample size and uses DPD-1 tablets, powders or liquids? If so, then you definitely want to check out DPD-1 ReagentStrips for free chlorine. They mix into solution much quicker, easier and cleanly than DPD powders and DPD tablets and have a much longer shelf life than DPD liquids.

The USEPA has accepted DPD-1 ReagentStrips for reporting water and wastewater analysis. That means the USEPA has found the DPD-1 ReagentStrip free chlorine testing procedure equivalent to its own USEPA method 330.5 for wastewater and Standard Method 4500-Cl G for drinking water when used with Palintest Chlorometer 1000 or equivalent.

Update — Want to use less water when testing for free (and total) chlorine? The eXact Chlorine Photometer requires 60% less test sample and meets the criteria for a USEPA Compliant Meter for free and total chlorine testing.

Per the request of several men and women currently serving in the United States Armed Forces and other branches of the Unites States Government, we will begin posting possible alternate products for popular (established) NSN’s (National Stock Numbers) related to water quality testing.

NSN: 6550012191061, 6550014257957 — Chlorine Test Tablets

“DPD REAGENT TEST TABLETS FOR CHLORINE ANALYSIS. PACKAGED IN INCREMENTS OF 100. LAMOTTE.”

Alternatives:

• DPD 1, 3 and 4 ReagentStrips — Faster and more convenient than traditional DPD test tablets. No MSDS required. Safe to use on production room floors of food processing facilities. EPA Compliant testing method. Packaged in bottles of 50 or individually wrapped in foil packs. Costs as low as 8 cents a test.

eXact^® Strip DPD ReagentStrips

Note: We have found that the products suggested above meet or exceed the specifications of the original NSN (National Stock Number) item. This does not mean, though, that you may substitute them in place of the item on a Government Contract. We provided the above information as possible sources of water quality testing products for consideration in future Contracts/Bids only.