Twenty-four hour notification means telephoning CDPH within 24 hours with prompt follow-up letter when individuals are exposed to an eye dose equivalent within 24 hours exceeding:

• A. 5 rems
• B. 15 rems
• C. 25 rems
• D. 50 rems

Answer: (B)

The key idea is that reporting requirements are tied to the regulatory limit for the lens of the eye. The occupational dose limit to the eye is 15 rem per year, so if a single 24-hour period delivers an eye dose equivalent that reaches or exceeds this annual limit, it triggers a mandatory 24-hour notification to the state with a follow-up letter. That’s why 15 rems is the threshold—it represents the point at which rapid reporting is required. A smaller dose, like 5 rem, would not meet the threshold, while larger doses (such as 25 or 50 rem) would also require reporting, but the value that defines the triggering point is 15 rem.