IEC 61874:2025 pdf download,Nuclear instrumentation – Geophysical borehole instrumentation to determine rock density (‘density logging’).

IEC 61874:2025 covers the specification and requirements for nuclear borehole logging equipment. It applies to systems comprising:

a borehole probe with a collimated gamma-ray source and a detector for measuring scattered radiation;
a hoisting and depth measurement system;
associated electronics and readout units.

IEC 61874:2025 establishes the terminology, apparatus types, general design, and technical requirements. It details the radiation, electrical, mechanical, safety, and environmental performance criteria, along with corresponding test and calibration methods. Issues related to electrical safety and radiation protection are addressed, and guidance is provided for the manufacturer’s operation and maintenance documentation.