ISO 19017:2015 is applicable to gamma radiation measurements on radioactive waste.Radioactive waste can be found in different forms and exhibit a wide range of characteristics, including the following:- raw or unconditioned waste, including process waste (filters, resins, control rods, scrap, etc.) and waste from dismantling or decommissioning;- conditioned waste in various forms and matrices (bitumen, cement, hydraulic binder, etc.);- very low level (VLLW), low level (LLW), intermediate level (ILW) and high level radioactive waste (HLW);- different package shapes: cylinders, cubes, parallelepipeds, etc.Guidance is provided in respect of implementation, calibration, and quality control. The diversity of applications and system realizations (ranging from research to industrial systems, from very low level to high level radioactive waste, from small to large volume packages with different shapes, with different performance requirements and allowable measuring time) renders it impossible to provide specific guidance for all instances; the objective of this International Standard is, therefore, to establish a set of guiding principles. Ultimately, implementation is to be performed by suitably qualified and experienced persons and based on a thorough understanding of the influencing factors, contributing variables and performance requirements of the specific measurement application.This International Standard assumes that the need for the provision of such a system will have been adequately considered and that its application and performance requirements will have been adequately defined through the use of a structured requirements capture process, such as data quality objectives (DQO).It is noted that, while outside the scope of this International Standard, many of the principles, measurement methods, and recommended practices discussed here are also equally applicable to gamma measurements of items other than radioactive waste (e. g. bulk food, water, free-standing piles of materials) or to measurements made on radioactive materials contained within non-traditional packages (e. g. in transport containers).