The document specifies minimum requirements for the use of animals in biological testing. This part is also intended; a) to establish guidelines which allow the scientist to respect life in general; b) to reduce the number of animal experiments and the number of animals used in experiments, among other ways by optimization of those performed; c) to minimize suffering and maintain the quality of life of the animals used in the experiments. This part applies to the experimentation performed on vertebrates. It does not apply to experimentation performed on less differentiated animals; nor does it apply to that part of the experimental work performed on isolated tissues and organs. This part also makes recommendations concerned with the aim of reducing the number of animals used of biocompatibility testing and when possible abolishing animal experiments in this areas.