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A bilateral intercomparison of disseminated transmittance standards.

O'Halloran, J (1999) A bilateral intercomparison of disseminated transmittance standards. NPL Report. COEM 40

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Spectrophotometry is a widely used technique for both qualitative and quantitative analysis in the pharmaceutical and chemical industries as well as in medical laboratories. The National Physical Laboratory (NPL) in the UK, and the National Institute of Standards and Technology (NIST) in the USA, both issue transfer standards in the form of solid filters that provide traceability for transmittance measurements to users in industry. The two laboratories have held an intercomparison to see how well these disseminated scales agree. The standards included both glass and metal-on-silica filters, with transmittances ranging from 90% to 1 %, calibrated at selected wavelengths between 250 nm and 635 nm. The results show an acceptable level of agreement between the two laboratories for transmittances between 90% and 10%. Further work will be required to establish the reasons for the poorer agreement for transmittances below 10%.

Item Type: Report/Guide (NPL Report)
NPL Report No.: COEM 40
Subjects: Optical Radiation and Photonics
Optical Radiation and Photonics > Materials and Appearance
Last Modified: 02 Feb 2018 13:18
URI: http://eprintspublications.npl.co.uk/id/eprint/1253

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