California Code, Health and Safety Code - HSC § 114750

(a) That there is shown to be a substantial public interest in the information intended to be obtained by the study.

(b) That the study will be performed by persons or agencies competent to handle and use the radioactive material safely and with due regard for potential effects on public health.

(c) That the study is planned so as to impose the least possible exposure to ionizing radiation consistent with achieving the study's desired objectives.

(d) That there is no likelihood that any person will be exposed to ionizing radiation in excess of guide levels published by the Federal Radiation Council. The department may, as a condition to its approval of a field tracer study, require a representative of the department to be present during the study.