Laboratory standard

National Institute of Standards and Technology (NIST). The NIST is the source of many of the standards used in chemical and physical analyses in the United States and throughout the world. The standards prepared and distributed by the NIST are used to caUbrate measurement systems and to provide a central basis for uniformity and accuracy of measurement. At present, over 1200 Standard Reference Materials (SRMs) are available and are described by the NIST (15). Included are many steels, nonferrous alloys, high purity metals, primary standards for use in volumetric analysis, microchemical standards, clinical laboratory standards, biological material certified for trace elements, environmental standards, trace element standards, ion-activity standards (for pH and ion-selective electrodes), freezing and melting point standards, colorimetry standards, optical standards, radioactivity standards, particle-size standards, and density standards. Certificates are issued with the standard reference materials showing values for the parameters that have been determined. 

Any site-related activities such as bench-scale laboratory and R D activities should comply with the OSHA Laboratory Standard (29 CER 1910.1450). R D activities involving pilot- or full-scale field operations should comply with HAZWOPER when there is reasonable possibility for worker exposure to hazardous wastes or substances or emergency response. 

The identity of the various models that will be used to demonstrate achievement of design requirements. (Some models may be simple space models, others laboratory standard or production standard depending on the need.)... 

Underwriters Laboratories Standard UL 525 (1994) applies to both deflagration and detonation flame arresters. It has also been approved as an ANSI standard. Its development is discnssed in Section 2.3.1. 

An important field of development is the batched flow production of metal nanoclusters attached to biomolecules such as DNA under GMP laboratory standards. This conjures up hopes of applying metallic nanomaterials coupled with drugs, antibodies, or with oligonucleotides for cell-specific cancer diagnosis and therapy. With the help of such nanometallic tools, it can be expected that diseases or predispositions to diseases will be diagnosed earlier with the help of nanodrugs than is possible at present. 

For a detailed discussion of the art of sample handling and data acquisition for blood gas measurements, see National Committee for Clinical Laboratory Standards. Blood gas pre-analytical considerations specimen collection, calibration, and controls Proposed Guideline. NCCLS publication C27-P, Villanova, Pennsylvania, NCCLS, 1985... 

NCCLS, National Committee for Clinical Laboratory Standards provides a medium for communication among professionals in healthcare, government, and industry in developing guidelines for clinical laboratory practices. 

NCCLS Infobase 99 (1999) NCCLS approved standards and guidelines. National Committee for Clinical Laboratory Standards, Wayne, PA. 

Wagner LR (1997) The college of American pathologist, 1946-1996 laboratory standards. Arch Path Labor Med 121 536-541. 

Institut de Recherches de la Siderurgie, France International Organization for Standardization ISO Council Committee on Reference Materials International Union for Pure and Applied Chemistry Laboratory of the Government Chemist, UK, formerly NPL National Bureau of Standards, USA, now NIST National Committee for Clinical Laboratory Standards, USA National Institute for Biological Standards and Control, UK Japanese National Institute for Environmental Studies National Institute of Occup. Health, Oslo, Norway National Institute of Standards and Technology, USA, formerly NBS,... 

A quick glance at Equations (1) through (5) shows sources of error that contribute to error in age, presuming that the assumptions used in calculating the equations hold (initial condition assumptions and the closed-system assumption). These include errors in the decay constants/half-lives, errors in the measurement of the pertinent isotope ratios, and in the case of Equation (3), the error in our estimate of initial °Th/ Th. Relationships among error in half-lives, laboratory standardization procedures, and °Th age are discussed in detail by Cheng et al. (2000b). 

Development of resistance to P -lactam antibiotics, including penicillins and cephalosporins, has significantly impacted the management of bacterial meningitis. Approximately 17% of United States pneumococcal CSF isolates are resistant to penicillin, and 3.5% of CSF isolates are resistant to cephalosporins.26 The Clinical and Laboratory Standards Institute (CLSI) has set a lower ceftriaxone susceptibility breakpoint for pneumococcal CSF isolates (1 mg/L) than for isolates from non-CNS sites (2 mg/L). Increasing pneumococcal resistance to penicillin G... 

NCCLS Document 1/L A 19-A. Primary reference preparations used to standardize calibration of immunochemical assays for serum prostate-specific antigen (PSA) Approved Guideline. NCCLS, Villanova, PA National Committee for Clinical Laboratory Standards (1996). 

Field spikes with laboratory standards as well as spraying solutions were taken at a wide range of concentrations to determine the stability of the samples during both sampling and storage and possible contamination during the sampling procedure. Field blanks were also taken. 

Comparison of test values with a conventional true value ( reference value ) of a (certified) reference material (RM, CRM). In method development and validation of analytical procedures, the comparison of experimental results with standards of diverse kind (laboratory standards, certified reference materials, primary standards) plays an essential role. The decision as to whether an experimental result hits the reference value depends not only from the result itself but also from its uncertainty interval. 

If or represents the reproducibility standard deviation and ar represents the repeatability standard deviation, the between-laboratory standard deviation, CTl, is calculated from the following ... 

SACHEM Inc. of Cleburne, Texas, manufactures various concentrations of tetramethylammo-nium hydroxide (TMAH) solutions to meet customer specifications. To ensure consistent performance, electronic industry requires very narrow concentration specifications for the solutions. In SACHEM s quality control laboratory, standardized acids such as HC1 or H2S04 are used as titrants for the TMAH solutions to check their concentrations. The performance of the assay titration is controlled by daily analysis of internal reference standards (IRSs). If the IRS results are within controlled limits, then the assay results of a product can be reported. If not, the results cannot be reported until the root cause is uncovered and eliminated. Safety glasses and gloves are worn while performing this work in the laboratory. 

Figure 7. A few examples of isotopic patterns of Ne, Ti and heavy elements in SiC and graphite grains are displayed. Absolute ratios are plotted for Ne (a) whereas abundance ratios relative to solar wind composition are plotted for Kr (c) and Xe (f). The remaining elements are plotted as %o deviations from laboratory standards. The data have been obtained on bulk SiC separates by traditional mass spectrometry for Ne (Jungck and Eberhardt 1979), Kr (Ott et al. 1988 Lewis et al. 1994), Sr, Ba (Ott and Begemann 1990 Prombo et al. 1993) and Nd (Richter 1995). SIMS techniques (caption continued on facing page)...

National Committee for Clinical Laboratory Standards. 1995, Performance Standards for Antimicrobial Disk Susceptibility, 5th Edition, Approved standard. NCCLS Document M2-A5, Villanova, PA. 

Flower chamomile drag (Chamomilae Flos) were dried in shielded room under laboratory standard temperature. 

National Committee for Clinical Laboratory Standards, 1996, Method for Broth Dilution Antifungal Susceptibility Testing Yeast Approved Standard, M27-A, 15, 10, NCCLS, VA Medical Center, Tucson, AZ. 

Procedures should be organized and indexed in the form of manuals and must be written in compliance with National Committee for Clinical Laboratory Standards (NCCLS) GP2-A2 (3). Technical procedures designed for use at the bench should be complete, easy to follow, and readily available to testing personnel. These procedures must contain the following information for each assay performed ... 

The study was performed in patients exposed to ionizing radiation after Chernobyl accident. Comparison groups included patients and healthy individuals exposed to the natural radiation levels. Control group included healthy volunteers who resided in Kyiv since Chernobyl accident Distribution by diagnosis is presented at table 1. Investigated persons were at the age of 43-72 (mean+SD for the exposed group 52,3 + 10,1 yrs for control group- 46,3 + 11,3 yrs). All studied persons participated by informed consent. Peripheral blood and bone marrow samples were obtained by a standard procedure (National. Committee for Clinical Laboratory Standards, 1991). Flow... 

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