X-Ray Standardization Program of the Bureau of Standards

Abstract

HomeRadiologyVol. 14, No. 4 PreviousNext EditorialX-Ray Standardization Program of the Bureau of StandardsPublished Online:Apr 1 1930https://doi.org/10.1148/14.4.416bMoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In AbstractIThe solution of the problems of X-ray standardization has arrived at a point where the Bureau of Standards is in a position to calibrate ionometers for the public.The discrepancies between different standardizing laboratories in regard to the magnitude of the r-unit are now small enough to be neglected in connection with medical applications. The basis for this conclusion is the agreement within 2 per cent, recently obtained by a comparison, through the cooperation of Dr. Glasser, of two instruments from the Cleveland Clinic with those used by the Bureau; and the fair agreement found earlier between the Cleveland Clinic instruments and those of the Reichsanstalt of Germany. Further comparisons will, of course, be made between the different national laboratories.IIAn ionometer sent to the Bureau may be calibrated for any condition of voltage and filtration desired, although all such instruments to be accepted for calibration, must be adequately controlled by such means as radium or uranium oxide. This will minimize the possibility of undetected damage occurring to the ionometers in transit.The following procedure is necessary to avoid delays and complication. Notify the Bureau as far as possible in advance of the shipment of the instrument, giving at the same time the type of instrument, date of purchase, method of controlling its calibration, type of X-ray machine with which it is used, peak voltage applied to the X-ray tube as actually measured with a sphere gap, and the half value layer in copper or the effective wave length of the radiation, with an explanation of how the measurement was made.IIIIf the ionometer has been calibrated previously, a copy of the calibration should be supplied in order to complete the Bureau's records for every instrument it handles.The cost of this service will depend upon the number of calibrations made for each instrument. A schedule of fees may be had upon request after sending in the information required above, in addition to stating the number of calibrations desired.Bureau of StandardsDepartment of Commerce, washington, D. C.Article HistoryPublished in print: Apr 1930 FiguresReferencesRelatedDetailsRecommended Articles RSNA Education Exhibits RSNA Case Collection Vol. 14, No. 4 Metrics Altmetric Score PDF download