Nuremberg Code
Directives for Human Experimentation

1. The voluntary consent of the human subject is absolutely essential. 

2. The experiment should be such as to yield fruitful results for the good of society. 

3. The experiment should be so designed and based on the results of animal experimentation and a knowledge of the natural history of the disease.

4. The experiment should be so conducted as to avoid all unnecessary physical and mental suffering and injury.

5. No experiment should be conducted where there is an a priori reason to believe that death or disabling injury will occur.

6. The degree of risk to be taken should never exceed that determined by the humanitarian importance of the problem to be solved by the experiment.

7. Proper preparations should be made and adequate facilities provided to protect the experimental subject against even remote possibilities of injury, disability, or death.

8. The experiment should be conducted only by scientifically qualified persons.

9. During the course of the experiment the human subject should be at liberty to bring the experiment to an end.

10. During the course of the experiment the scientist in charge must be prepared to terminate the experiment at any stage, if he has probable cause to believe, in the exercise of thegood faith, superior skill and careful judgment required of him that a continuation of the experiment is likely to result in injury, disability, or death to the experimental subject. (Link)