Document: NRC Regulatory Guide
Document ID: 1859c547-c10c-4ce4-ad2e-e54f7b66d4ef
Document Type: regulatory_guide
Title: Laboratory Investigations of Soils and Rocks for Engineering Analysis and Design of Nuclear Power Plants + HISTORY – HISTORY 07/2014 – DG-1256 , Proposed Revision 3 08/2001 – DG-1109 , Proposed Revision 2 (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1318/ML13186A032.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.138
CFR Part: 
CFR Title: 

Content:
Soil, Rock, and Construction Materials Testing” (Ref. 11), describes specifications for balances and scales. In addition, Reference 7 contains valuable discussions of common problems, precautionary measures, and control of errors in the testing of soils. Scholey et al. (1995, Ref. 12) present a review of instruments for measuring small strain. Germaine and Ladd (1988, Ref. 13) discuss problems associated with triaxial testing of saturated cohesive soils, including errors caused by the equipment or the procedures used. 1.3. Calibration a. Investigators should calibrate all test apparatus and instruments used for quantity measurement against certified calibration standards before putting them into service. Thereafter, they should verify the calibration at regular intervals. The necessary frequency for recalibration varies according to the susceptibility of the apparatus to change and the required precision of measurement. Physical length or volume measuring apparatus such as metallic tapes, rules, pycnometers, cylinders, or graduated cylinders need not be calibrated unless altered by visible wear or damage. b. An external agency with equipment directly traceable to the National Institute of Standards and Technology should periodically recalibrate weights and other equipment used as standards to calibrate test instruments. c. Instrument calibrations may be performed in house using the specific laboratory’s own standards of references. DG-1256, Page 5 For additional information on calibration, U.S. Army Corps of Engineers EM 1110-2-1909, “Calibration of Laboratory Soils Testing Equipment” (Ref. 14) issued in 1986, recommends procedures for calibrating testing equipment. ASTM D3740, “Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction” (Ref. 15) and Sallfors (1989, Ref. 16) offer information on equipment calibration and its importance, respectively. 1.4.