REPORT FOR ANALYTICAL CHEMISTS
90% of the laboratories reported that they obtained reference ma terials from the National Bureau of Standards. Most of the labora tories utilized at least three of the listed sources. The particular type of analysis involved governed, to a great extent, the source of the stan dard, of course. No significant re lationship could be determined be tween the source and the analytical technique. It is apparent that whenever the NBS has a specific standard of interest available, lab oratories will utilize this source. For more specialized areas, the other sources are also used to a sig nificant degree. Foreign sources, such as the British Society of Glass
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ANALYTICAL CHEMISTRY
Technology, were prominently men tioned. Replies to this question are sum marized in Table II. Many laboratories reported that they are partially supplying their own reference materials when suit able standards are not available. This source was defined as "inhouse." Cooperative efforts be tween mutually interested labora tories are under way to meet the needs of the laboratories. About 59% of the laboratories reported they were engaged in using "inhouse" reference materials. The adequacy of these noncertified ref erence materials was termed satis factory by about 56% of the users.
Table 1. Analytical Techn ques That Require New or Improved Standard Reference Materials Infrared, near i n f r a r e d , a n d ultraviolet spectroscopy Phosphorescence Fluorescence C o l u m n a n d thin-layer c h r o m a t o g r a p h y Nuclear m a g n e t i c resonance spec rometry H o t extraction o f gases, inert gas f usion A m i n o acid analysis Organic microanalysis Gel p e r m e a t i o n c h r o m a t o g r a p h y Gas c h r o m a t o g r a p h y BET surface area X-ray spectroscopy, diffraction A t o m i c a b s o r p t i o n spectroscopy Flame e m i s s i o n spectroscopy Electron probe microanalyzer Spark source m a s s s p e c t r o m e t r y Viscometry Tensile t e s t i n g Pyrohydrolysis A c t i v a t i o n analysis Vapor pressure o s m o m e t r y , molecu lar wei ght d e t e r m i n a t i o n
Table I I . Replies to Question Concerning Sources of Star dards»
Source
Number of Laboratories That Reported Using This Source
NBS C o m m e r c i a l , Domestic In-House C o m m e r c i a l , Foreign API AEC U. S. Pharmacopoeia FDA National Formulary U. S. Geological Survey U. S. Bureau of Mines " Total n u m b e r of laboratories r e p o r t i n g == 78
70 62 46 26 23 17 15 12 11 7 6
