U.S. Nuclear Regulatory Commission
Question 411: Under 10 CFR 19.12, what is the minimum training that licensees must provide to visitors who will enter a restricted area (where the occupational dose limits apply)?
Answer: 10 CFR 19.12, "Instructions to Workers," requires that training (instruction) be provided to "all individuals working in or frequenting any portion of a restricted area." Frequenting an area means to pay frequent visits to the area or to be in the area often. Therefore, 10 CFR 19.12 does not apply to infrequent visitors who will not be working in the restricted area.
However, 10 CFR 19.12 does apply to visitors or other individuals (a) who will be working in the restricted area or (b) who are expected to be in the area often. (Thus, 10 CFR 19.12 does require instruction of anyone working in a restricted area, even if that work is infrequent.) Licensees have the responsibility to determine which individuals are frequent visitors and which are not. Although not required by 10 CFR 19.12, in accordance with good radiation protection practice, infrequent visitor(s) should be provided with a trained escort who will provide the visitor(s) with the information needed for protection from any potential radiological hazards.
(Reference: 10 CFR 19.12)