[en] After a brief review of the principle of operation and principal calibration characteristics of accelerometers, this article presents in the middle frequency range ie, 5 Hz to 10 kHz, two absolute methods of calibration of their sensitivity. These two methods consist of: a method of interference measurement of the accelerometers displacement which for a given frequency will permit calculation of the resultant level of acceleration; an electrical reciprocity method. They require the measurement of mechanical and electrical levels which can be easily referred to National Standards and the interrelation between their frequency range and their acceleration levels permits their cross-comparison

[en] Accurate dose measurements is an important parameter to ensure the effective irradiation process. Developments of the accurate dose measurement system and an effective standardization of radiation beam at Unit Tenaga Nuklear are discussed. Emphasis is given on the selection of the suitable dosemeter system, beam standardization and quality control programme to ensure the established system is traceable to the International standards. The dosimeter was supplied to the irradiation plants in Malaysia for monitoring of irradiation process. The measured dose is used as an evident indicating the reliability of accurate irradiation process especially for the product to be exported to other countries

No abstract available

[en] The fabrication, conditioning and analytical checking of a series of Pu metal standards realized by the ''Commission d'Etablissement des Methodes d'Analyses'' at the CEA, are described. They can be employed for the calibration of the chemical and physical determination methods of Pu and used as calibration standards in the analysis of traces. The results obtained are given

[en] An essential part of any measurement control program is adequate knowledge of the uncertainties of the measurement system standards. Only with an estimate of the standards'' uncertainties can one determine if the standard is adequate for its intended use or can one calculate the total uncertainty of the measurement process. Purchased standards usually have estimates of uncertainty on their certificates. However, when standards are prepared and characterized by a laboratory, variance propagation is required to estimate the uncertainty of the standard. Traditional variance propagation typically involves tedious use of partial derivatives, unfriendly software and the availability of statistical expertise. As a result, the uncertainty of prepared standards is often not determined or determined incorrectly. For situations meeting stated assumptions, easier shortcut methods of estimation are now available which eliminate the need for partial derivatives and require only a spreadsheet or calculator. A system of simplifying the calculations by dividing into subgroups of absolute and relative uncertainties is utilized. These methods also incorporate the International Standards Organization (ISO) concepts for combining systematic and random uncertainties as published in their Guide to the Expression of Measurement Uncertainty. Details of the simplified methods and examples of their use are included in the paper

No abstract available

[en] Solid, unquenched, radiophosphorescent standards for use in the day-to-day calibration of bottom viewing photometers (luminometers) were prepared by encapsulating commercially-available phosphor powders that are excited to phosphoresce by the β^- decay of ⁶³Ni (t_0.5 = 96 yr) or ¹⁴C (t_0.5 = 5730 yr). The encapsulated photometer standards have remained mechanically and photometrically stable since their fabrication, which in some cases is 3 years ago. An equivalent level of visible luminescence emitted from the standards of up to 2.3 x 10¹⁰ photons.s^-1 was achieved by using an appropriate amount of radioactivity and the proper phosphor. The phosphor used in the standards could be chosen such that the radiophosphorescence emission spectrum corresponded approximately to the chemiluminescence or bioluminescence spectrum under investigation. (author)

[en] The D₂O concentration of the Canadian Primary Standard has been reviewed and an accurate redetermination of the deuterium content has been made using the absolute method recently developed at CRNL. A new value of 99.9720 +- 0.0006 wt percent has been determined and its use is recommended. On and after November 1, 1984 the assigned concentration values of secondary standards based on the Canadian Primary Standard should be changed correspondingly as should the value for heavy water in reactors and inventory and the associated reactor grade specifications. The new value of the Canadian Primary Standard is in good agreement with results from international intercomparisons, is directly established with absolute determinations, and is easily verifiable in the future. An appendix describes a container which facilitates intercomparisons and long term storage of standards and their handling in interlaboratory comparisons

[en] Polydisperse, non-porous microspheres are required with well-defined aerodynamic properties to determine if enhanced settling of micron-sized aerosol particles occurs in the presence of larger particles (gravitational agglomeration). Glass spheres with claimed unimodal narrow distributions were evaluated using a TSI Aerodynamic Particle Sizer (APS33B). The size fractions containing particles in the range from 1 to 5 μm aerodynamic diameter were truly unimodal, but the fractions which were supposed to consist solely of particles larger than 5 μm aerodynamic diameter contained a significant proportion of submicron particles. (author)

No abstract available