Encyclopedia
Cave
Cave-in - change in well diameter
Source: ORDER OF Gosatomnadzor of Russia dated December 25, 2003 No. 135
"ON APPROVAL AND INTRODUCTION INTO FORCE OF METHODOLOGICAL GUIDELINES FOR IMPLEMENTING SUPERVISION TO ENSURE RADIATION SAFETY AT OBJECTS CONDUCTING GEOPHYSICAL STUDIES USING RADIOISOTOPIC SOURCES"
(along with "METHODOLOGICAL GUIDELINES... RD-07-16-2003")