National Institute of Standards and Testing

For very accurate manometer readings, the NIST (National Institute of Standards and Testing) has a compiled list of eight possible errors that can develop while reading manometers. These errors introduce extremely small variations and therefore are not included here. If you need to read a manometer to the sensi-... 

The experimental portion of this work was carried out in two separate laboratories on two very different and important solid substrate materials, carbon chars and natural minerals of geochemical interest. The first involves excellent work performed by Victor Dietz et. al. at the National Bureau of Standards (NBS), now the National Institute of Standards and Testing (NIST). " This research was meticulously carried out before the advent of... 

The LAP equipment tester should have the equipment necessary to carry out the required challenge of the LAP systemJ This equipment should be in good working order and calibrated to a National Institute of Standards and Testing (NIST)-traceable standard at least annually, or more often as indicated by the manufacturer s specifications or equipment performance NIST-traceable calibration ensures the uniformity, accuracy, and serviceability of all test equipment as well as proper maintenance and care by the user. The NIST-traceability of equipment calibration is substantiated by a detailed calibration certification letter, issued by the calibrating authority for each piece of equipment. 

National Institute of Standards and Testing, Gaithersburg, MD, NIST/SEMATECH e-Handbook of Statistical Methods available online at http //www.itl.nist.gov/div898/handbook/index.htm accessed 22 May 2007. 

Reference material sets which are certified by the International Confederation for Thermal Analysis and Calorimetry (ICTAC) are available through the US National Institute of Standards and Testing (NIST), and are listed in Appendix 2.2. High-purity metals and organic compounds including polymers have been certified. If the standard reference material must be dispensed with a syringe into the sample vessel (for example cyclohexane), care must be taken to ensure that only one droplet is formed in the sample vessel. Multiple transition peaks will be observed if there is more than one droplet present. The transition temperatures listed in Appendix 2.2 are the statistical mean values of measurements made in a number of laboratories and institutes. The ICTAC reference materials are certified for temperature calibration only and not for enthalpy calibration. The reference temperatures in Appendix 2.1 should be used if very accurate calibration of the instrument is required. In order to determine the heat capacity Cp ) of a sample, sapphire (a-alumina, AI2 O3) is used as a standard reference material. The Cp of... 

It is assumed here that the pressure and temperature measuring devices are properly calibrated. They should be traceable to the National Institute of Standards and Testing (for USA). The problem is to measure what one thinks is being measured. Here is a hst of potential problems and their consequences. 

With generous federal support, primarily Irom the Defense Advanced Research Projects Agency (DARPA), the Office of Naval Research (ONR), the Army Research Office (ARO), the National Science Foundation (NSF), the US Dept, of Commerce, National Institute of Standards and Testing (NIST), the... 

The accuracy of a spectrophotometer can be checked by measuring absorbances for a series of standard dichromate solutions that can be obtained in sealed cuvettes from the National institute of Standards and Technology. Absorbances are measured at 257 nm and compared with the accepted values. The results obtained when testing a newly purchased spectrophotometer are shown here. Determine if the tested spectrophotometer is accurate at a = 0.05. 

Color and Appearance Collaborative Reference Program, Collaborative Testing Services, Inc., Herndon, Va., previously MCCA-NBS Collaborative Reference Program on Color and Color Differences, National Institute of Standards and Technology, Washiagton, D. C., 1991. 

In Tables 6.3 and 6.4 RMs of three major producers are mentioned, i.e. the World Health Organization (WHO, International Standards), BCR (European Union, CRMs) and the National Institute of Standards and Technology (NIST, USA, SRMs). Some important national producers of clinical reference materials are the Chemicals and Inspection Testing Institute (CITI, Japan), National Institute for Biological Standards and Control (NIBSC, UK), and Deutsche Gesellschaft fiir Klinische Chemie (DGKC). There are numerous commercial producers of secondary reference materials. 

The melt flow rate of a polymer is the weight of polymer in grams that extrudes from a standard capillary die under a standard load, at a standard temperature, over a ten minute period. The term melt index is used exclusively for polyethylene melt flow rate is the preferred term for all other polymers, We measure melt flow rates using a piece of equipment called a melt indexer . The capillary dimensions, testing temperature, and load are specified for a given polymer by the National Institute for Standards and Testing. 

Braun, E. Levin, B.C. Paabo, M. Gurraan, J.L. Clark, H.M. Yoklavich, M.F. Large-Scale Compartment Fire Toxicity Study Comparison with Small-Scale Toxicity Test Results, NBSIR 88-3764. National Institute of Standards and Technology, Gaithersburg, MD, 1988. 

Some reference material producers/suppliers use different names to describe their materials. For example, a Standard Reference Material (SRM) is a certified reference material issued by the National Institute of Standards and Technology (NIST), while European Reference Materials (ERMs) are CRMs produced under a joint collaboration between three European reference materials producers, i.e. BAM (Federal Institute for Materials Research and Testing, Germany), IRMM (European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Belgium) and LGC (UK). 

Currently, there is no mechanism to effectively share reactive chemical test data throughout industry. The feasibility of a publicly available test database has not yet been studied by industry or government. Reactive chemical experts at one company visited by CSB expressed an interest in working with the National Institute of Standards and Technology (NIST) to develop such a database. 

Certificate of Analysis, Standard Reference Material 869a column selectivity test mixture for liquid chromatography (polycyclic aromatic hydrocarbons), National Institute of Standards and Technology (NIST), Gaithersburg, MD, 1998. Available at http //www.nist.gov/SRM... 

Accuracy is determined after a test calibration using one out of the four following ways. The difference between precision and accuracy is clearly shown in Figure 1. In the first case, if available, e.g., from the National Institute of Standards and Technology (NIST), reference samples (e.g., pharmaceutical in matrix) with defined true reference values are analyzed. Then true and measured values can directly be compared, but this case is rare. 

During the same period, NIST (the National Institute of Standards and Technology, formerly the National Bureau of Standards) reported that the cost of nondiagnostic medical tests in the United States at the end of the 1990s was 36 billion, about one-third of the total cost of testing. Not all these tests are chemical, and so not all the retests would have been a result of poor quality in a laboratory, but the figure is very large (U.S. Senate 2001). 

Neutral-Density Filters. The empty reference filter holder (air reference) and then filters of various transmittance values at 440, 465, 546.1, 590, and 635 nm are scanned (these wavelengths are selected to minimize interaction between the absorbance and wavelength scales of the spectrophotometer being tested [12]). Compare the results with the values in the certificates. The certified values for the National Institute of Standards and Technology (NIST) SRM 930-e series glass... 

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