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| Frequently Asked Questions | ||
| Technical Service | ||
| Customer Service | ||
| Website | ||
| How do I get all of the neat material out of the vial? |
| What does “sonicate” mean? |
| What is a "Technical Mixture" and why is that important in my use of Reference Standards? |
| Why is Nitrite not included in your IC mixes? |
| Why is Mercury always separate in your ICP mixes? |
| Are Uranium and Thorium products radioactive? Are they naturally occurring or depleted isotopes? |
| Why are some of the RMs you're selling unstable (labile) i.e. have a short expiration date? |
| Why does AccuStandard use ampules for most of their Organic Reference Materials? |
| There appear to be crystals in my ampule, what should I do? |
| Are there Special Considerations for Volatile Analytes? |
| Why do I get Poor Recoveries on Endrin and DDT? |
| Why do I have problems when analyzing Phenols and Nitrosamines? |
| Are your Standards NIST Traceable? |
| How can I be assured of AccuStandard’s Commitment to Quality? |
| How do I know the shelf life before I purchase a standard? |
| What is AccuStandard’s Expiration Dating Policy? |
| Understanding the Uncertainty Value on your Certificate of Analysis |
| What does my Certificate Mean? |
| Why is a Cold Pak recommended with some standards? |
| What is the "On-Going Stability Program" and how does that save money? |
| Even though it doesn’t look like
the product is in there, it is. Small amounts (5-10 mg) of powder often
are spread over the surface of the vial and cap. If the chemical is a liquid
it may coat the walls as a thin layer invisible to the eye. To recover all of the contents contained in a vial of neat material please use the procedure described below: 1. Wipe the outside of the vial (containing the Standard) clean and dry (including the cap). 2. Weigh the entire unit on an analytical balance. Record the weight to the nearest 0.1 mg. 3. Carefully transfer the contents to a volumetric flask using a suitable solvent. Rinse the cap and vial several times to assure a complete transfer. 4. Dry inside and outside of the vial and cap with mild heat or inert gas. 5. Weigh the empty dry vial on the same analytical balance to the nearest 0.1 mg and calculate by difference the amount of material transferred. |
| What does “sonicate” mean? |
| If AccuStandard has a product with known or suspected solubility problems that can be corrected by sonication, “sonicate” is written on the label. An example of when this could happen is with products that may precipitate out of solution when they get cold. During shipment we cannot control the temperature of the products, and some of the less soluble analytes may start to precipitate out. This precipitation may be so slight that it cannot be detected visually, however, could affect the outcome of the analysis. If you receive a product that says sonicate, the solution should be warmed to room temperature and then the sealed ampule should be sonicated in an ultrasonic bath for approximately fifteen minutes. Invert the ampule several times to achieve homogeneity, allow the sample to return to room temperature, and then the standard is ready for use. |
| What is a “Technical Mixture” and why is that important in my use of Reference Standards? |
Products which are “Technical
Mixtures”, known by a variety of names such as “Tech Mix”, “Technical
Product”, and other names, are not pure chemicals, but are very
necessary in analytical chemistry. Hence, they are available as Reference
Standards. They are mixtures of multiple chemicals, so chromatograms
of Tech Mixes will have multiple peaks. None of the peaks are “impurities”,
rather they are all components important as ingredients in the product. |
| Why is Nitrite not included in your IC mixes? |
| AccuStandard has found that mixes that contain both Nitrate and Nitrite are not stable over long periods of time. Typically, the Nitrite oxidizes to Nitrate. This creates a problem for long-term storage of these solutions. Therefore, in order to provide the most stable solution, AccuStandard supplies the Nitrite as a separate solution. Diluting the two solutions together just prior to use will ensure the most accurate values for these standards. |
| Why is Mercury always separate in your ICP mixes? |
| Mercury has unique properties that make it not very
stable in the presence of other analytes. Some of these properties are: Mercury can easily be reduced to the metallic state, tends to volatilize easily, can precipitate in the presence of even minute amounts of halogens (such as HCl fumes), and can plate onto some surfaces. As a result of these properties Mercury is provided as a separate solution, and if required, can be mixed with the other elements just before analysis. |
| Are Uranium and Thorium products radioactive? Are they naturally occurring or depleted isotopes? |
| AccuStandard sells only the 1000 µg/mL concentrations of the Uranium and Thorium. These products are made from naturally occurring Uranium and Thorium and have been tested and fall below the IATA 0.002 µCi/g limit for radioactive materials. AccuStandard cannot guarantee the exact isotopic distribution in either of these products. |
| Why are some of the RMs you're selling unstable (labile) i.e. have a short expiration date? |
| Certain
chemicals, due entirely to their structure (which if changed will result
in a different chemical), are more likely to react than others. The reactivity
would be enhanced by a) shelftime, b) temperature, c) solvent d) by other
analytes present (if the standard is a multi-analyte mixture) e) air, light.
Typical examples would be for: Pesticides: Tetraethyl pyrophiosphate (TEPP), Trinitrotoluene (TNT) solutions, Aldehydes and Ketones (eq. Airolein and Methylethyl ketone form adducts with inethoinol as a solvent, Acids (Phenols, Carboxylic acids) will form salts with bases (Amines), Anthracene will react with the oxygen in the air above the solution (if it is not purged with nitrogen between usage) to form anthraquinone (keeping the solution dark will also prevent this from happening). |
| Why does AccuStandard use ampules for most of their Organic Reference Materials? |
| Like most Organic Chemical Reference Material manufacturers, AccuStandard uses ampules. There are many positive reasons for using ampules. One of the most important is that once sealed, they provide a long term, air tight and relatively inert environment that protects the product for long term storage. Ampules preserve the concentration of the analytes since neither the analytes nor the solvent can escape. Ampules do have some inconveniences associated with them, such as snapping them without breaking them and not being able to use a pipette in the neck of the ampule. When snapping ampules, we suggest using an AccuSnap to protect your hands. Alternatively, a folded paper towel, or thick gloves can also provide protection. To transfer from an ampule to another container we suggest either using a clean narrow tipped disposable Pasteur pipette. Once the transfer has been made, the designated portion of the AccuStandard label can be removed from the ampule and attached onto the transfer container for easy identification. To dilute the standard directly from the ampule, we suggest using a CLEAN glass syringe. |
| There appear to be crystals in my ampule, what should I do? |
| Sometimes precipitation or crystallization may appear in a product. This can occur with products that are close to saturation and have gotten cold. If this happens, the solution should be warmed to room temperature and then the sealed ampule should be sonicated for approximately fifteen minutes. Invert the ampule several times and allow the sample to return to room temperature. The standard is now ready for use. If the sealed product has crystals at the top of the outside of the ampule, it may indicate a pinhole break in the seal. In this case, please call AccuStandard Customer Service for assistance. |
| Are there Special Considerations for Volatile Analytes? |
| Volatile Analytes, especially gases,
can be troublesome to analyze. To provide the best possible standard we
suggest the following procedures: 1. Keep the ampules cool (follow the storage conditions on the label). 2. Prior to use, invert the ampule several times to ensure the gases are in the solution, not in the headspace. Mixing too vigorously can cause the gases to be lost as well. 3. Use freshly opened ampules whenever possible. 4. When transferring, take care to avoid losses of the very volatile components. For example, holding the barrel of a syringe in your hand can warm it enough to lose some of the most volatile components. 5. If using the purge and trap (PT) system is giving questionable results, try a direct liquid injection. If the results are not as expected, there may be a problem with the PT apparatus. |
| Why do I get Poor Recoveries on Endrin and DDT? |
| Poor recoveries on these analytes can result from an injector port problem. Try cleaning the port or replacing the liner. Most times this will correct the problem. Removing the first few inches of a capillary column can also help. Since elevated temperatures contribute to the breakdown problem, using cool on-column injection methods can be used to avoid this issue. |
| Why do I have problems when analyzing Phenols and Nitrosamines? |
| Since Phenols and Nitrosamines can react with the active sites on a column, they can sometimes give inconsistent results from run to run. By saturating these sites, the problem should go away. To do this, run a standard that is between 2 to 5 times higher than your highest calibration point. This can be repeated if necessary until the problem is alleviated. Alternatively silylation can be performed on the column (contact column manufacturer for more details). |
| Are your Standards NIST Traceable? |
| Yes, when available, AccuStandard provides NIST traceability. The traceability link is stated on the Certificate of Analysis that is provided with the Standard. |
| How can I be assured of AccuStandard’s Commitment to Quality? |
| AccuStandard’s quality system is ISO 9001:2000 and ISO 17025 accredited. AccuStandard's quality system undergoes multiple audits each year and has become stronger and more robust with each review. We hold regular interdepartmental Non-Conformance meeting , in accordance with our ISO work instructions. The failure analysis determines the root cause and the appropriate corrective action for each non-conformance. |
| How do I know the shelf life before I purchase a standard? |
| Most Inorganic Single Standards have a shelf life of 3 years while most mixes have a shelf life of 12-18 months. Most Organic Standards have shelf life of a year or more. Some Organic Standards are more thermally labile and last a shorter period. These are marked with a penguin icon in the catalog, and they should be ordered with a cold pack to lessen the temperature effects during shipment. |
| What is AccuStandard’s Expiration Dating Policy? |
| Chemical Reference Standards, like
all chemicals, can undergo changes or decomposition under certain thermal
conditions or as a result of interactions with air, moisture, and other
chemicals and solvents. The likelihood and extent to which this happens
is dependent on the specific chemical structure, and can be predicted based
on experience and an extensive knowledge of the behavior of the particular
chemical. Most Standards manufacturers state Expiration Dates and Storage Conditions on their products. For the chemist who uses the product, understanding the way these dates are generated will allow them to choose products with the best accuracy and reliability. AccuStandard uses the “On-Going Stability Program” data to determine Expiration Periods (over 21 years of data on over 35,000 chemical products). We compare data from the latest lot of a given product to historical data. Based on this information, we assign a period ranging from three months to three years to each product. If a customer has product left at the end of its expiration period, our QC Department may re-analyze the product and may extend the expiration period if it is still within specification. This saves money, especially on specials, and reduces your facility's waste stream, which is good for the environment. Customers sometimes get confused if another Standards manufacturer offers them a longer expiration date on a product than AccuStandard assigns to ours. As long as the chemicals and their environment are the same (same analytes, solvent, concentrations, and holding conditions), the stabilities will be the same, too. Any differences in time will be due strictly to a lack of knowledge or understanding by the party promising a longer stability. There is a wide range of approaches to assigning Expiration Dates to reference standards. We invite customers to compare the approaches from other manufacturers and to contact us when a question arises. In this way the chemist using the product can understand the capability and professionalism of their Standards manufacturer. |
| Understanding the Uncertainty Value on your Certificate of Analysis |
| Several regulating bodies require
reporting the uncertainty in a certified value. These include ISO-17025:1999,
which says in section 5.4.6.3: “When estimating the uncertainty of
measurement, all uncertainty components which are of importance in the given
situation shall be taken into account using appropriate methods of analysis.
Note 1 Sources contributing to the uncertainty include, but are not necessarily
limited to, the reference standards and reference materials used…” In addition, quantifying uncertainty aids in understanding the possible errors that can occur when assigning a value for a particular analysis. However, in order to be useful the chemist using the value for a Certified Reference Material needs to understand what the uncertainty means. Uncertainty IS NOT the same as error. “Error is defined as the difference between an individual result and the true value.” An error value can be used to correct a value, for example a temperature correction for a pH reading. Uncertainty IS essentially the amount of doubt that can be cast onto a value. The uncertainty range represents a summation of the estimates of the unpredictable variations that can reasonably be expected to occur during a measurement. In many ways the uncertainty represents a “worst case” scenario. The range reported for uncertainty represents the chance that if everything that could go wrong, did, and all in one direction (high or low), the value could be off by this amount. Essentially, the uncertainty is the amount of doubt that can be cast onto a value. It is NOT the amount of error in the value. The reported value may indeed be very close to the true value, and therefore have a negligible error. However, the uncertainty may be very large, simply because the analyst is unsure of how close the result is to the true value. Therefore, when looking at an AccuStandard certificate, if the expanded uncertainty is reported as ± 4% this does not mean that the value has a possible error range of 8%. The uncertainty represents the combination of all the uncertainties of all the steps that went into the preparation of the material, and the assignment of the value. Uncertainty calculations and theory can be very confusing. For more in depth information, the Eurachem/CITAC Guide, examples of uncertainty calculations, and other useful information can be found at: http://www.measurementuncertainty.org/ 1 Quantifying Uncertainty in Analytical Measurement, Second Edition, Eurachem/CITAC Guide. SLR Ellison, Ed., p. 5. 2 Ibid |
| What does my Certificate Mean? |
| There are many different ways of describing
uncertainty, or ranges that are reported on certified values. The uncertainty
value discussed above is one of the more useful. Other wording you may encounter
on certificates include: The uncertainty is expressed as the “expanded uncertainty”… —Reporting expanded uncertainty allows the uncertainty to be expressed so that it encompasses a larger interval around the value, typically an expanded uncertainty is reported as being at the 95% confidence interval. —To obtain the expanded uncertainty, a coverage factor is used. A coverage fact is typically between 2 and 3. Therefore, if the original uncertainty calculation shows an uncertainty of 2%, but you want to report this value in the 95% confidence interval, you must multiply it by 2 to get an expanded uncertainty of 4%. —The expanded uncertainty often results in a number that appears to be very large, however, statistically it is the preferred manner of reporting uncertainty. This product is guaranteed accurate to ± x% of the certified value… —This means that the manufacturer is confident enough to certify that their preparation methods, analysis, and history with this product will provide a certified value in a range of ± x% of the certificate value. —This statement is generally more generic than the uncertainty, and is NOT independent or contradictory of uncertainty. It is a guarantee of the confidence of the manufacturer to support their product. Tolerance of the weighing procedure and dilution error add a maximum of ± 0.5%. —This if very similar to the above. It is basically a statement of the tolerance of their internal procedures. Uncertainty based upon balance and glassware accuracy… —A statement like this means that an uncertainty calculation was done, but rather than assessing ALL the possible sources of uncertainty (such as purity, repeatability, moisture, etc.), they are only using the items stated. This will generally give a better-looking number, but may not encompass the full scope of contributing factors. The most important part of the uncertainty is that you understand how it fits into your laboratories’ analysis and work accordingly from there. |
| Why is a Cold Pack recommended with some standards? |
| Certain of the Chemical Reference
Standards are thermally labile. This means they are highly susceptible to
change at room temperature or above. For this reason, AccuStandard states
the storage conditions on the label. In some of these cases, AccuStandard
also recommends that the product ship in a “Cold Pak”, which
is a styrofoam container that has an ice pack in it. The purpose of the Cold Pak is to delay the exposure of the product to higher temperatures. The purpose is NOT to keep the product frozen. The product will not immediately go out of specifications when the Cold Pak melts or when the product reaches room temperature. Temperature related effects would begin to exhibit themselves at various times (up to many months) after this happens. The Cold Pak simply delays exposure to higher temperatures. When a product is shipped with a Cold Pak, the customer should also consider requesting next-day delivery (where available) and should avoid having the shipment sent on a Friday unless it is approved for Saturday Delivery. |
| What is the "On-Going Stability Program" and how does that save money? |
| It means you may be able to use that expired standard instead of paying for a new one. Here's how it works: AccuStandard has faithfully logged every analysis and re-test of every product for the last twenty years, along with all the parameters. Customers call daily asking if a particular expired lot can get re-certified for a longer expiration period. Our QC Department will review the data, including re-analyzing the retain for that lot if necessary. A high percentage of the time we can re-certify the product for additional time. In those cases we send new labels and Certificates of Analysis (free of charge!). That's the value to our customers of the AccuStandard "On-Going Stability Program". |
| Do you have a Distributor in my country? |
| Can I order directly through you? |
| How do I save on shipping costs on web orders |
| How fast can we get custom mixes quoted? |
| Why are expiration dates so different (often shorter) than other companies for the same product? |
| What shipping charges can I expect? |
| We have authorized distributors in over 70 countries. For a list of Exclusive Distributors click here. All inquiries and orders should be directe to them. Other distributors are Non-Exclusive and customer may contact them directly or contact AccuStandard directly. |
| Can I order directly through you? |
| We have authorized distributors in over 70 countries. For a list of Exclusive Distributors click here. All inquiries and orders should be directe to them. Other distributors are Non-Exclusive and customer may contact them directly or contact AccuStandard directly. |
| How do I save on shipping costs on web orders |
| A credit will be issued on the order, in the approximate amount of the average ground transportation cost, which is $10 on Domestic orders, and $20 on International orders. This offer applies to all web orders of at least $250 on Domestic orders and $500 on International orders (after discounts) on AccuStandard brand catalog items. |
| How fast can we get custom mixes quoted? |
| We try to get custom mixes quoted within 12 hours of request. If you have a special request that is urgent, please let us know and we will try to accommodate your needs as soon as possible/immediately (depending on ability and type of mix being formulated). |
| Why are expiration dates so different (often shorter) than other companies for the same product? |
| AccuStandard is very quality conscious and doesn’t like to take chances with the products that we supply to our customers. We value our reputation as a supplier that wants to only provide our customers with products that we are comfortable in our knowledge of their working for that period of time. |
| What shipping charges can I expect? |
| There are some rare charges especially
for International shipments that we will not list, but the main shipping
charges are as follows: Shipping (FedEx, UPS, etc.), Hazardous shipping fees, International orders often require Customs, Duty, and other charges. These cost can be reduced or eliminated: No "expediting charge" for same day shipments, NoHaz single element AA and ICP standards require no hazardous charges. AccuStandard's CSRs can prepare a "Pro-Forma" invoice which will show you all these costs before the order is placed (except International costs such as customs, etc. Visit "101 Ways to Save" link for ways to reduce shipping and handling costs. |
| I’m not registered on your web site. Can I still place an order? |
| I want my order shipped/billed to a different address from the one I registered. How can I do that? |
| How do I order a custom quoted item on the web site? |
| I found a listing for the catalog number I want, but there is no price. Why? |
| On the Order Confirmation page, what is the User Account number below the shipping choices? Does my AccuStandard Customer Number go there? |
| How do I register on the web site? |
| Do I have to supply an email address? |
| I just registered on your web site, but my password doesn't work. What’s wrong? |
| I am a registered user trying to place an order. Where do I enter my AccuStandard Customer Number? |
| I want to change information that I gave in my original registration |
| Absolutely! Just go to the order form and fill in the catalog numbers you want. If you have an AccuStandard customer number, note that in the Special Instructions box at the bottom of the Order Confirmation form before submitting your order. Once you’ve placed your order, you might want to consider registering so your customer number, address information, and customer specific terms and conditions fill in automatically when you come back. |
| I want my order shipped/billed to a different address from the one I registered. How can I do that? |
| When you reach the Order Confirmation form simply change any information as desired for that order. The system will automatically fill in the information you gave when you registered, but you can change any of it on an order-by-order basis. |
| How do I order a custom quoted item on the web site? |
| Simply fill in the catalog numbers from your quote on the order form on the web site. Then reference your quote number in the Special Instructions box at the bottom of the Order Confirmation form before submitting your order. (Since this is a new custom formulation being made just for you, no description or price will show up on the web site.) |
| I found a listing for the catalog number I want, but there is no price. Why? |
| Only catalog listed items show prices on the web site. Items that are sold only as part of sets (not for individual sale) or that are custom items will not show prices. |
| On the Order Confirmation page, what is the User Account number below the shipping choices? Does my AccuStandard Customer Number go there? |
| No. That is in case you want AccuStandard to bill your shipping charges to your own FedEx or UPS account number. If you are not registered and logged in, put your AccuStandard customer number in the Special Instructions box at the bottom of that page. |
| How do I register on the web site? |
| Although it is not necessary to register in order to
place orders or use the site, registration enables the site to auto-fill
in your company and address information for orders, literature requests,
or custom quote or technical service requests. This information can easily
be changed on individual requests without affecting the registration information
on file. Also, if you include your AccuStandard customer number you will see your discounted prices instead of full list price when viewing or ordering catalog items. You need to complete the registration form on the web site. To reach the form click here or select the 'Customer Login' link at the top of the screen, then clicking on the first line of red text "Register for a user name and password". Once there, fill out the form as indicated. Please be aware that both user name and password are case sensitive, and must be at least 8 alpha-numeric characters long. (no spaces, dashes, or special characters). Once you have submitted your completed registration form your request will be processed by an authorized AccuStandard employee. As soon as your registration has been activated you will receive an e-mail confirming your user name and password. |
| Do I have to supply an email address? |
| Yes. Your registration confirmation will be sent only to your registered email address. Also, request for user name/password reminders or any changes to your user information will only be accepted from the registered email address on file. |
| I just registered on your web site, but my password doesn't work. What’s wrong? |
| Nothing is wrong. Your registration must be processed
by an authorized AccuStandard employee. You will receive an email as soon
as your account has been activated. In the meantime, you can still place
orders on the web site. If you have already received a confirming email and still can’t log in, make sure you are typing your user name and password correctly. Remember that both user name and password are case sensitive! If you continue to have problems, use the 'Ask a Question' link to contact the Help Desk, or call 203-786-5290 / 800-442-5290. |
| I am a registered user trying to place an order. Where do I enter my AccuStandard Customer Number? |
| As long as you are logged on, you don't need to enter it. The system will automatically transmit the AccuStandard Customer Number you supplied when you registered as part of your order. Itf you did not supply your Customer Number when registering, please use the 'Ask a Qustion' link to send the correct number to the Help desk. Be sure to include your name, company name, and user name. Your online account will be corrected. |
| I want to change information that I gave in my original registration |
| Use the ‘Ask a Question’ link at the bottom of the page to send an email to the Help Desk. Be sure to include your name and company name for verification. Include what information you want changed. A confirmation will be sent to you once the changes have been made. Remember to send the email from the email address you used when you registered! |
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