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Alcohol v. H1N1. Alcohol 1, H1N1 0.

Posted by Cole-Parmer on December 28, 2009

Bacdown® Gel No-Rinse Skin Sanitizer, 16 oz With the amount of bottles of alcohol-based hand sanitizer available for public use at hospitals, schools, day-care facilities and malls now outnumbering the billions of viruses and bacteria on even the dirtiest of human hands, you may be wondering if this stuff actually works.

Is it better than hand washing? Does it create mutant strains of alcoholic germs? Might my retirement savings have actually increased had I invested in the makers of Purell last year?

In fact, alcohol-based hand sanitizers are tremendously effective in preventing the spread of the seasonal flu, H1N1, colds and other viral- and bacterial-based diseases; and sales are through the roof.

There are in fact few negative consequences about this hand-sanitizer mania sweeping the country, although the gels do have their limitations.

Wash or squirt?

Most respectable public health experts will tell you that hand washing with ordinary soap and water is the most effective way to remove germs from your hands. But “effective” is a questionable term. The recommendation calls for hand washing with soap and warm water for at least 20 seconds to create a full lather and to reach all crevices of your hands and wrists, as advocated on Sesame Street yet rarely put into practice.

Alcohol-based hand sanitizers kill most types of bacteria, viruses and fungi in a few seconds. While rubbing your hands with sanitizer for 15 seconds is ideal, poor hand-sanitizer use still beats poor hand washing.

And people seem to use hand sanitizers often — so much so that, from a public health standpoint, although proper hand washing is technically superior than alcohol gels most of the time, hand-sanitizer mania will likely be a more effective means to reduce disease transmission. Studies have shown how hand sanitizers reduce gastrointestinal illnesses in households and curb absentee rates in schools and workplaces.

Trash the sink?

Alas, you can’t rely solely on alcohol-based hand sanitizers. Alcohol can kill bacteria but not necessarily clean your hands. That is, it does not remove dirt, which includes organic material such as blood or feces. Soap and water must be the first choice in restrooms.

Also, there are a few key germs that alcohol doesn’t kill well, such as the norovirus or E. coli, which is why soap and water is best during cooking, too.

Alcohol-based hand sanitizers are best precisely where you see them the most, in hallways, offices and other public areas. They can rid your hands of germs you just picked up before you inadvertently shove them into your body via your nose, mouth or eyes.

Alcohol kills bacteria usually by dissolving its cellular membrane. It’s a serious killer, like fire or bleach, and germs don’t develop resistance to it. Also, the alcohol evaporates quickly after killing the first layer or so of germs on your skin. This means that, although benevolent bacteria are killed, enough remain on lower levels or elsewhere up the arm to re-colonize. Fast evaporation, coupled with moisturizers, also means this won’t dry out your skin.

Anti-bacterial soap, ironically, is largely considered the worse thing you can use to kill germs. This is because antibacterial agents kill many but not all bacteria and then linger on the skin to enable the remaining bad bacteria to develop a resistance.

Watch out for the cheap stuff

To be effective, alcohol-based hand sanitizers must contain at least 60 percent alcohol. Some cheaper brands contain less and are no better than water. Worse, they offer false protection.

Sixty percent pure alcohol can pack a punch if ingested. Fortunately, as reported in the American Journal of Emergency Medicine in 2006, even hospital workers using hand sanitizers all day long do not absorb discernable levels of alcohol into their blood.

There is a small risk that a child could drink or lick an alcohol-based hand sanitizer. That’s something parents and teachers need to monitor. Only a few reports of poisonings have been reported. Even alcoholics will have a rough time abusing this because the gels taste rather bad. I prefer not to reveal how I know.

View our complete selection of:

Hand Sanitizers (http://www.coleparmer.com/catalog/product_index.asp?cls=56777&referred_id=5618)

Hand Soaps (http://www.coleparmer.com/catalog/product_index.asp?cls=56778&referred_id=5618)

Article compliments of Christopher Wanjek, LiveScience’s Bad Medicine Columnist.  Fighting the Flu: Do Hand Sanitizers Work?   Posted: 27 October 2009 09:49 am ET.  http://www.livescience.com/health/091027-hand-sanitizers.html

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IS YOUR WORKPLACE LOUD? Read how employers can minimize hearing loss.

Posted by Cole-Parmer on December 18, 2009

Approximately 30 million American employees are exposed to excessive workplace noise, according to the Occupational Safety and Health Administration. Workers run the risk of hearing loss if they are exposed to an average of more than 85 decibels (dB) over an 8-hour workday. OSHA takes excessive noise seriously, and its regulation CFR 1910.95 requires employers in noisy workplaces to:

  • Reorganize equipment, facilities, and/or tasks to reduce noise levels.
  • Monitor individual and work area noise levels and report high levels to employees.
  • Test employee hearing, with annual follow-ups.
  • Provide hearing protection where needed.
  • Provide training in the selection, proper fit, and use of hearing protection

Workers should be aware that there are many other sources of loud noise that can cause permanent hearing loss as well. iPods and cell phones are often used at dangerously high volumes and of course, rock concerts are off the charts in terms of loud noise. Holding annual hearing protection training is a good opportunity for employers to remind their workers about the risks associated with recreational noise.

Louise Vallee, vice president, Chubb & Son, spoke at Safety 2009, this year’s American Society of Safety Engineers conference. “Baby Boomers have attended rock concerts and engaged in noisy recreational activities for nearly 50 years,” she said. Recent studies indicate that close to 40 million baby boomers are experiencing some degree of hearing loss—twice as many as expected. Vallee added that corporate executives must be educated about recreational hearing loss issues, which further support the need for hearing conservation programs for the workplace.

In addition, The National Hearing Conservation Association (NHCA) has petitioned OSHA to reduce the permissible exposure limit (PEL) for noise. A letter from the group cited the fact that nearly 22 million American workers are exposed to hazardous noise on a daily basis and that occupational hearing loss continues to plague diverse industries.

Citing research from NIOSH and other sources, the association claims that American workers face a considerable risk of noise-induced hearing loss from working long term under the present limits.

If workplace monitoring determines that employees need to wear hearing protection, such as earmuffs, earplugs, canal caps, or a combination thereof, employers should enforce the use of the proper personal protective equipment. Also, they should help their employees to get a good fit to provide the most protection.

The hearing protection training should include instructions to take these preventive measures:

  • Keep ear protectors clean; wash them regularly according to manufacturer’s instructions.
  • Wash your hands thoroughly before inserting earplugs.
  • Inspect your ear protectors before putting them on. If they’re loose or cracked, report it.
  • Workers also need to recognize the symptoms of hearing damage. Tell your workers to let you know immediately if they experience the following symptoms:
  • Noise or ringing in ears
  • Trouble hearing people when they speak
  • Trouble hearing certain high or soft sounds
  • Needing a higher volume on the TV or radio—high enough that other people complain

Article compliments of Safety.blr.com. 

View Cole-Parmer’s complete line of hearing protection equipment:  http://www.coleparmer.com/catalog/product_index.asp?cls=7514&referred_id=5618

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Mouthwash causes cavities!

Posted by Cole-Parmer on November 26, 2009

Acidity contributes to the development of dental cavities. The source of this acidity is often attributed to sugar fermentation by endogenous bacteria in the mouth, or to acidic foods and drinks, which lower salivary pH. Paradoxically, oral health mouthwashes may also cause dental cavities, largely due to the inclusion of ethanol (EtOH/”alcohol”) as an antiseptic agent, which can be oxidized to acetic acid. However, the potential deleterious effect of these mouthwashes has not been adequately assessed, nor have the chemical changes in pH and total ethanol been
evaluated over time. Here we present data demonstrating changes to pH, total acid, and total ethanol in several popular mouthwashes over time. These changes increase acidity and thus demonstrate an increased risk of dental cavities.  Finally, we evaluate the chemical mechanism of these changes, and propose preventable solutions.

Full article is available here:  Determination of pH, total acid, and total ethanol in oral health products: oxidation of ethanol and recommendations to mitigate its association with dental caries 
Compliments of:  Chunhye Kim Lee and Brian C. Schmitz

Test your own mouthwash using a Cole-Parmer PH/Ion Meter .

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Tamiflu not working for some H1N1 patients

Posted by Cole-Parmer on November 24, 2009

Four patients at Duke University Medical Center in Durham, N.C., and at least five in an unidentified hospital in Wales have become infected with H1N1 viruses that no longer respond to treatment with Tamiflu. Flu viruses swap genes as part of their normal evolution; that means resistant viruses could quickly spread worldwide, says Duke’s Daniel Sexton.

Read more:  http://www.usatoday.com/news/health/2009-11-23-swinefluupdate23_ST_N.htm

Prepare yourself for H1N1 using safety products from Cole-Parmer

Snippet compliments of Steve Sternberg, USA TODAY.

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Barbie and Disney toys still have high levels of lead

Posted by Cole-Parmer on November 23, 2009

By JENNIFER C. KERR, Associated Press Writer Jennifer C. Kerr, Associated Press Writer

WASHINGTON – Children’s toys carrying the Barbie and Disney logos have turned up with high levels of lead in them, according to a California-based advocacy group — a finding that may give consumers pause as they shop for the holiday season.

The Center for Environmental Health tested about 250 children’s products bought at major retailers and found lead levels that exceeded federal limits in seven of them. Lead can cause irreversible brain damage.

Among those with high lead levels: a Barbie Bike Flair Accessory Kit and a Disney Tinkerbell Water Lily necklace. The group said it also found excessive lead in a Dora the Explorer Activity Tote, two pairs of children’s shoes, a boys belt and a kids’ poncho.

California Attorney General Jerry Brown has sent letters to Target, Wal-Mart and the other retailers who sold the seven products, warning that children’s goods on their store shelves were found to contain illegal levels of lead and should be pulled immediately.

The findings released Tuesday come about a year after a product safety law that ushered in strict limits on the amounts of lead and chemicals allowed in products made for children 12 years and younger. Congress passed the law after a slew of recalls of lead-tainted toys in 2007, including several Mattel-related recalls that involved more than 2 million toys.

Mattel said it licensed the Barbie name to Bell Sports for the bike accessory kit found with high lead, but did not make or sell it. Bell said the kit was an older product that passed safety tests in 2007, but the company didn’t know it was still on store shelves.

Disney said the Tinkerbell necklace was tested by its licensee, Playmates Toys, before being distributed — and that it complied with all federal and state consumer safety regulations.

The Center for Environmental Health in Oakland, Calif., said the Barbie toy was bought at Tuesday Morning and the Tinkerbell jewelry was purchased at Walgreens. The other products the center said had high lead came from TJ Maxx, Sears, Wal-Mart and Target.

The center’s executive director, Michael Green, said parents “need to know that there are still some lead problems on store shelves.”

The center did an initial round of testing on products and sent the ones singled out as having high lead to an independent laboratory for additional testing and confirmation.

The Consumer Product Safety Commission, which regulates toys and thousands of other products, is looking into the matter.

Commission Chairman Inez Tenenbaum held a meeting with parents and consumers Tuesday in New York to praise the new safety protections provided in the consumer law, known as CPSIA. She said lead recalls are down this year and that CPSIA should give consumers greater confidence while shopping for toys during the holiday season.

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Why is Juan Valdez so bitter? It’s not the caffeine.

Posted by Cole-Parmer on November 16, 2009

Published with permission. Initially published in the IFT Weekly Newsletter, August 22, 2007

What makes coffee so bitter, aside from being constantly cast as a wake-up caller? Two classes of compounds have been ID’d as the perpetrators, according to chemists in Germany and the United States who say they have identified the chemicals that appear to be largely responsible for java’s bitterness, a finding that could one day lead to a better tasting brew. Their study, one of the most detailed chemical analyses of coffee bitterness to date, was presented Tuesday at the American Chemical Society national meeting in Boston.

Research by others over the past few years has identified an estimated 25 to 30 compounds that could contribute to the perceived bitterness of coffee. But the main cause of coffee bitterness has remained largely unexplored until now, the researchers say.

“Everybody thinks that caffeine is the main bitter compound in coffee, but that’s definitely not the case,” said study leader Thomas Hofmann, Ph.D., a professor of food chemistry and molecular sensory science at the Technical University of Munich in Germany. Only 15 percent of java’s perceived bitterness is due to caffeine, he estimates, noting that caffeinated and decaffeinated coffee both have similar bitterness qualities.

Roasting is the key factor driving bitter taste in coffee beans. “So the stronger you roast the coffee, the more harsh it tends to get,” Hofmann says, adding that prolonged roasting triggers a cascade of chemical reactions that lead to the formation of the most intense bitter compounds.

Using advanced chromatography techniques and a human sensory panel trained to detect coffee bitterness, Hofmann and his associates found that coffee bitterness is due to two main classes of compounds: chlorogenic acid lactones and phenylindanes, both of which are antioxidants found in roasted coffee beans. The compounds are not present in green (raw) beans, the researchers note. Ironically, the lactones and the phenylindanes are derived from chlorogenic acid, which is not itself bitter.

Chlorogenic acid lactones, which include about 10 different chemicals in coffee, are the dominant source of bitterness in light to medium roast brews. Phenylindanes, which are the chemical breakdown products of chlorogenic acid lactones, are found at higher levels in dark roasted coffee, including espresso. These chemicals exhibit a more lingering, harsh taste than their precursors, which helps explain why dark-roasted coffees are generally more bitter, Hofmann says.

Perception of bitterness can also be influenced by how the coffee is brewed.. Espresso-type coffee, which is made using high pressure combined with high temperatures, tends to produce the highest levels of bitter compounds. While home-brewed coffee and standard coffee shop brews are relatively similar in their preparation methods, their perceived bitterness can vary considerably depending on the roasting degree of the beans, the amount of coffee used, and the variety of beans used.

Some instant coffees are actually less bitter than regular coffee, Hofmann says. This is because their method of preparation, namely pressure extraction, degrades some of the bitter compounds. In some cases, as much as 30 to 40 percent fewer chlorogenic acid lactones are produced, leading to a reduced perception of bitterness, he says.

“Now that we’ve clarified how the bitter compounds are formed, we’re trying to find ways to reduce them,” Hofmann says. He and his associates are currently exploring ways to specially process the raw beans after harvesting to reduce their potential for producing bitterness. They are also experimenting with different bean varieties in an effort to improve taste. But so far, none of these approaches—details of which are being kept confidential by the researchers—is ready for commercialization, he notes.

What makes coffee bitter?
Oral Presentation, August 21, 2007
American Chemical Society National Meeting
Boston, Mass.

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Finding flu vaccine information in one easy place

Posted by Cole-Parmer on November 12, 2009

Google has recently added flu vaccine information to Google Maps.   Read below for more info.

This year, it’s especially important to have clear information on what you can do to prepare for the flu season. With this in mind, we are happy to share a new feature for the U.S. which allows you to more easily find locations near you for getting both the seasonal and H1N1 flu vaccine. After expanding Google Flu Trends to a total of 20 countries and 38 languages, allowing more people to see near real-time estimates of flu activity, we began brainstorming with the U.S. Department for Health and Human Services (HHS), their flu.gov collaborators and the American Lung Association on the flu shot finder and other ways Google can be helpful to people this flu season.

You can check out the flu shot finder at www.google.com/flushot. The same tool will also be available shortly on www.flu.gov and the American Lung Association websites. It’s important to note that this project is just beginning and we have not yet received information about flu shot clinics for many locations. In addition, many locations that are shown are currently out of stock. We launched this service now in order to help disseminate information about locations where vaccines are available, and also to make more vaccine providers aware of the project so that they can contribute.


Especially given slower than expected vaccine production, we think it’s important to bring together flu shot information in a coherent manner. We’ve been working with HHS, the Centers for Disease Control and Prevention (CDC) and state and local health agencies to gather information on flu vaccine locations across the country, particularly for the H1N1 flu vaccine (both the nasal-spray vaccine and the shot). At the moment we have data for locations of flu vaccine directly from 20 states and counting. We are also continuing to add information from chain pharmacies and other providers in all 50 states; today, you’ll find results from chains such as Walgreens, CVS and PDX participants, such as Kmart, Duane Reade, WinnDixie and Giant Eagle.

Of course you should still call flu vaccine providers ahead of time to find out more about availability and eligibility for the two vaccines.

We hope to continue providing you with relevant information to help keep you and your loved ones healthy.

Posted by Roni Zeiger, M.D., Product Manager and Jennifer Haroon, Product Marketing Manager.    11/10/2009 09:15:00 AM

Re-posted via courtesy of Google:  http://googleblog.blogspot.com/2009/11/finding-flu-vaccine-information-in-one.html

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Less Is More: Buying Inexpensive Flowmeters

Posted by Cole-Parmer on November 11, 2009

Accuracy, repeatability, reliability, installation ease, and price – these are some of the basic criteria on which flowmeters are selected. And while it may be preferred to have the best flowmeter that money can buy, it is not always necessary to buy that most expensive one. For example, you may not need the most accurate flowmeter available, whereas, the same is not necessarily true of repeatability – especially if you use your flowmeter to control a process or a batching operation. But even in such a case, you may not need to buy the most repeatable flowmeter available.

Reliability varies as well from flowmeter to flowmeter, between different flowmeter technologies and even within similar technologies. In fact, reliability may vary within a single manufacturer’s product line. And face it, reliability costs money: The more reliable the flowmeter is expected to be, the more costly its purchase price is anticipated to be.

In some cases, you may be able to purchase several “less reliable” flowmeters for the same price that you would pay for a single unit of the most reliable flowmeter. And sometimes, but not always, installation ease of a flowmeter costs more. Keep in mind that installation ease is not correlated with accuracy or reliability; sometimes you have to give up accuracy or even reliability to get easy installation.

Applied Cost Analysis Price is a fairly good indicator of a flowmeter’s limitations. But that doesn’t mean that it is a good indicator of “how good” the flowmeter actually is. “How good” is really a function of how well matched the flowmeter is for your application.

As applications get more difficult, the number of flowmeters that work will decrease and the price of the flowmeter that can perform well in that application will increase. Conversely, as applications become easier, the number of flowmeters that can perform well will increase, whereas the price of those flowmeters will drop. This is an important point. Many flowmeter users immediately purchase the kind of flowmeter they are familiar with or the kind they believe to be the most accurate or reliable without actually thinking through the application. In many cases, you can save time and money by evaluating the application first and then selecting the flowmeter based on what will actually fit the application. Indeed, you can often plan the application so that you can use an inexpensive flowmeter if you start early enough in the design stage.

For example, if you have a conductive liquid at ambient temperature and moderate pressure and you have provided sufficient straight run both up– and downstream from the meter and you have sized the meter to produce approximately 60 percent of signal at the application’s average flow rate, then you can use any flowmeter you want with the appropriate materials of construction. Or if you have a gas flow at reasonable temperature and pressure and you’ve provided an adequate piping configuration, then you are free to use many different types of gas-flow devices.

In another example, if you are simply totalizing flow over a daily, weekly or monthly period, a variety of flowmeters will be adequate. The longer the baseline over which you are totalizing, the more accurate your total will be, regardless of what flowmeter you use. The flow totals from sewer-flow data loggers that take data every five minutes or so are known to be as good as continuous measurements totalized in the same location.

As a final example, if you are controlling a metering pump or other chemical feed device, you need only have a flowmeter in which the accuracy is better than that of the chemical feed device itself. It isn’t necessary to use a terrifically accurate flowmeter with a chlorine gas feeder, which is accurate to +/-4 percent of full scale.

So how do you figure out if you can use an inexpensive flowmeter? Simply study your application. If the application parameters can be done with the inexpensive flowmeter to the desired accuracy, repeatability, reliability and cost effectiveness, then use the cheapest flowmeter you can find.

If you really want to make sure that you are getting the least expensive flowmeter that will work adequately in your application, reverse the field. Start by setting a cost target for the flowmeter. Set a low one. Examine all the flowmeters under that cost target against your application. If none fits, raise the cost target and redo from the start. Keep raising the cost target bar slightly; doing so will permit you to work with, as well as evaluate, different flowmeter types and those more costly flowmeters that were over the bar previously. Eventually you’ll hit a flowmeter that will perform adequately. Buy that one.

View our complete selection of Flow meters

About the Author Walt Boyes is a senior member of ISA and current vice president of ISA’s Publications Department. He is a writer and consultant who has delivered numerous technical papers. He has more than 25 years in the practice of flow control.

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Oh sh*t, it’s on fire. Using a chemical compatibility database can save your job, and your life.

Posted by Cole-Parmer on November 9, 2009

See if your materials pass the Chemical Compatibility test! 

Chemical Compatibility Database

When you are working with potentially hazardous chemicals, chemical compatibility is a crucial part of product selection, especially when selecting tubing, pumps, fittings, flowmeters, and other products. Using this database, you can be assured the materials that your products are made from will not be negatively affected by chemicals in the fluids or gases.

Our interactive online Chemical Compatibility Database is a smart, simple, and quick resource for finding the safest materials for your application. With its straightforward, easy-to-use interface, you’ll find definitive answers for all your chemical compatibility needs. It’s no wonder that this database is one of the most utilized tools on the Cole-Parmer Web site!

To see if your materials interact with the chemicals you wish to use, simply select your material and chemical used. If you have multiple materials or chemicals, you can select “All” to view a complete list of chemical effects. Click Submit to determine the compatibility level.

You can also refine your search by using the Compatibility Level option to see which materials have “A-Excellent” compatibility with a certain chemical.

For your safety, Cole-Parmer generally recommends those materials which have an “A-Excellent” compatibility with the selected chemical. You should never use a material with a chemical that has “D-Severe” compatibility.

Don’t forget to bookmark the Chemical Compatibility Database—this simple and important tool is guaranteed to help keep your workspace safe!

Chemical Compatibility Database

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Stop! Don’t drink that water. Check out this brief article on Water Testing.

Posted by Cole-Parmer on November 6, 2009


Water testing is the continous sampling of various liquid streams and the analysis of their quality. These liquid streams include watercourses such as rivers and lakes, groundwater, recirculated cooling streams, boiler feedwater or condensate, and process effluents.

Water testing is not only a vital element of preserving a safe public drinking supply and a healthy environment, it can also improve industrial process efficiency for better products at reduced cost.

Our selection of water testing equipment includes test kits for bacteria and chemical compounds; colorimeters; multiparameter meters for measuring pH, ORP, conductivity/ salinity/total dissolved solids (TDS), dissolved oxygen (DO), and temperature; and turbidimeters.

Bacterial Test Kits

Eliminate time-consuming culture/plating techniques for convenient bacterial counts and assays.

Colorimeters

Measure the light absorbed by your sample after it reacts with a reagent that produces a color change. Since the intensity of absorbed light is proportional to the concentration of the compound, colorimeters accurately indicate the concentration of various compounds in your sample. Many colorimeters work with specific test kits for easy analysis. This reduces operator error, whether in reading color changes or in measuring reagents.

Multiparameter Meters

Measure pH, ORP, conductivity/salinity/total dissolved solids (TDS), and/or dissolved oxygen (DO)/biological oxygen demand (BOD).

Test Kits for Chemical Compounds

Contain prepared reagents and standards that let you easily determine the concentration of specific compounds in the sample. We offer titrimetric and colorimetric test kits for several compounds including ammonia, chlorine, carbon dioxide, heavy metals, and many others.

Colorimetric test kits:  These tests determine the concentration of a substance. The higher the concentration of a substance, the darker the color developed in the test.

Other elements can interfere with the accuracy of the tests. Read kit instructions for appropriate adjustments.

Titrimetric test kits: The concentration of a substance in a sample solution can be determined by titrimetic tests. After the sample is treated with an indicator, a standard titrant is added until a color change indicates a completed reaction. The amount of titrant used coresponds to the concentration of the substance being tested.

Turbidimeters

Turbidity in water is caused by suspended and colloidal matter such as clay, silt, finely divided organic and inorganic matter, and plankton and other microscopic organisms.

Quantify the turbidity of your sample by measuring the light scattered at a 90¡ angle to a source light beam. The meter compares the light scattered by sample particulates to light-scattered in a fluid with known turbidity and displays the measurement in nephelometric turbity units (NTU). The presence of dissolved, color-causing substances that absorb light may cause a negative interference.

Turbidimeters with scattered-light detectors located at 90° to the incident beam are called nephelometers. Nephelometers are relatively unaffected by small differences in design parameters and therefore are specified as the standard instrument for measurement of low turbidities. Poor measurement technique can have a greater effect on measurement error than small differences in instrument design.

Determine turbidity as soon as possible after sample is collected to ensure examination under original conditions.

  1. Gently agitate samples to ensure a representative measurement. If storage is required, cool to 4°C to minimize microbiological decomposition of solids.
  2. Keep cells scrupulously clean, inside and out, and discard if scratched or etched. Never handle them near the instrument’s light beam.
  3. Fill cells with samples and standards—allow sufficient time for bubbles to escape. Because small differences between sample cells can significantly impact measurement, use either matched pairs of cells or the same cell for both standardization and sample measurement.

Coagulation-Flocculation Jar Test of Water: This is a general procedure for the evaluation of a treatment to reduce dissolved, suspended, colloidal, and nonsettleable matter from water by chemical coagulation-flocculation, followed by gravity settling. The practice provides a systematic evaluation of the variables normally encountered in the coagulation-flocculation process. The coagulation-flocculation test is carried out to determine the chemical, dosages, and conditions required to achieve optimum results. The primary variables to be investigated using the recommended practice include, (but are not limited to): chemical additives, pH, temperature, and the order of addition and mixing conditions.

Significance: This jar test permits the evaluation of various coagulants and coagulant aids used in the treatment of water and waste water for the same water and the same experimental conditions. The effects of concentration of the coagulants and coagulant aids and their order of addition can also be evaluated by this practice.

View our complete selection of Water and Industrial Liquid Sampling products.
View our complete selection of Water Purification products.
View our complete selection of Water Testing products.

Related Articles

Good Laboratory Practices for Taking Turbidity Measurements
Water Purification

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