How Specialty Gases Differ from Industrial Gases

Written by Bob Davis

Continued from page 1

Laboratory analysis to quantify all components and impurities in a specialty mixture is nearly always critical. A formal document known as a Certificate of Accuracy or Certificate of Analysis is provided for each cylinder containing a specialty mixture, and also for some specialty pure gases. This certificate specifiesrepparttar concentration values for all contents, as well as other important information suchrepparttar 136550 method of blending, type of laboratory analysis and reference standard used to preparerepparttar 136551 mixture and expiration date. Expiration date refers torepparttar 136552 length of timerepparttar 136553 components of a mixture remain at their certified concentrations withinrepparttar 136554 specified tolerances. Depending onrepparttar 136555 stability ofrepparttar 136556 components, shelf life can vary from as little as six months to two years or more. Special cylinder preparation processes, such as Scott’s Aculife cylinder inerting treatments, can be used to condition cylinder interior walls in order to extend a mixture’s shelf life.

Specialty gases are typically not used in nearly as large a quantity as industrial gases and are supplied in steel or aluminum high-pressure cylinders containing up to 3000 pounds of pressure per square inch/gauge (psig). Hence, they are sometimes referred to as cylinder gases or bottled gases. The cylinder itself is typically not included inrepparttar 136557 price ofrepparttar 136558 specialty gas it contains and must be returned torepparttar 136559 gas supplier whenrepparttar 136560 gas has been depleted. A nominal monthly cylinder rental is usually charged untilrepparttar 136561 cylinder is returned. Many specialty gases are also available in small, portable and non-returnable cylinders such as Scott’s SCOTTY Transportables. Other specialized containers include lecture bottles that are often used in laboratories and floating piston-type cylinders that are used to contain volatile liquid phase mixtures.

The cost of specialization Due to blending technology, cylinder preparation, laboratory analysis and statistical quality control necessary to produce specialty gases, cost is much higher than for lower grade industrial gases. An A-size cylinder containing 218 cubic feet of a low grade of helium suitable for filling party balloons might cost little more than $50. The same cylinder containing 99.9999% pure research grade helium, with a total impurity of less than one part-per-million (1 ppm), would cost about $500. That’s still a bargain considering 144 cubic feet of a three-component EPA Protocol mixture having an analytical accuracy of 1% may cost as much as $1,500. As with any other specialized product,repparttar 136562 end cost of a particular specialty pure or gas mixture is largely determined byrepparttar 136563 degree of difficulty and complexity involved in its preparation.

Considerations when purchasing specialty gases Purchasing specialty gases can be a daunting task. Because of today’s bottom line-oriented business climate, one might consider selecting a specialty gas product based strictly on price. Be careful! While in some cases organizations such asrepparttar 136564 EPA may dictate minimum accuracy and manufacturing processes for certain gas mixtures, there are few industry-wide standards for specialty gas quality. Blending, analytical and cylinder preparation procedures vary between suppliers of specialty gases. Moreover, suppliers do not always use common nomenclature when describing their products. Even when product names arerepparttar 136565 same,repparttar 136566 characteristics ofrepparttar 136567 gases can be quite different. The best advice is to carefully evaluate your application needs before purchasing. Then talk with a specialty gas expert to be sure you fully understand howrepparttar 136568 characteristics of a particular pure gas or gas mixture will either meet or possibly compromise your application. Remember also that most specialty gases requirerepparttar 136569 use of specialized delivery equipment that is constructed of materials that will protect gas purity and integrity.

Bob Davis is the Environmental Marketing Manager with Scott Specialty Gases, the world’s largest producer of EPA Protocol gases and a leading global manufacturer of specialty gases for all types of applocations. More information on the company and Scott’s products can be found at

New Evidence Shows The Lasting Effects of Pesticide Exposure

Written by Dave Saunders

Continued from page 1

Some ofrepparttar insecticides used byrepparttar 136303 licensed farmers overrepparttar 136304 past 25 years are no longer available commercially. DDT, a well known example of an organochlorine, has been banned for use inrepparttar 136305 US since 1972. Organophosphates, such as malathion, chlorypyrifos, and diazinon, have been banned or restricted for home and garden use inrepparttar 136306 US. However, some ofrepparttar 136307 pesticides examined, including carbaryl and some pyrethroids, are available to home gardeners, although in different formulations and in lower concentrations, which may make them less hazardous.

"Becauserepparttar 136308 participants in this study are telling us they have never been previously diagnosed with pesticide poisoning or medically treated for any exposure to any pesticide, we are led to conclude that their symptoms are related to moderate lifetime exposure," said Dr. Kamel.

Organophosphate insecticides, such as diazinon, disulfoton, azinphos-methyl, and fonofos, are used widely in agriculture and aroundrepparttar 136309 house. With over 25,000 brands of pesticides available inrepparttar 136310 United States,repparttar 136311 use of organophosphates is probably more common than most people suspect. Many toxic nerve agents, used in milary applications are also also organophosphates.

Organochlorines are named as organic molecules bound with chlorine atoms. These include PCBs and DDT. Some organochlorines are also known as xenoestrogens because of their ability to mimic estrogen inrepparttar 136312 body. These compounds have been theorized to be atrepparttar 136313 root of a variety of estrogen-dominate illnesses in woman, like endometriosis and in wide spread genetic defects in wildlife likerepparttar 136314 three-legged frogs reported in Florida.

While this report does focus on farmers whose "moderate exposure" is likely higher than most people inrepparttar 136315 home, this report should serve as a caution to indiscriminate use of such products inrepparttar 136316 house and especially inrepparttar 136317 presence of children and those with weakened immune systems. Many of these compounds were initially popular because of their hardiness inrepparttar 136318 environment, meaningrepparttar 136319 compounds last longer to provide more killing effectiveness. This may be a good feature forrepparttar 136320 economics of agriculture and warfare, but at what consequence?

Dave Saunders is a certified nutritional educator, wellness coach, member of the American International Association of Nutritional Education (AIANE) and author. He is also the host of a weekly, nation-wide telephone lecture on health and nutrition. For additional information, please visit his site on nutrition and glyconutrients at or or email Dave at

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