What is the annual occupational dose limit for the lens of the eye?

• A. 50 mSv (5 rem)
• B. 100 mSv (10 rem)
• C. 150 mSv (15 rem)
• D. 500 mSv (50 rem)

Answer: (C)

The lens of the eye is one of the most radiosensitive tissues in the body, so the dose limit is set separately from the whole body to specifically protect vision. Historically, the annual occupational dose limit for the lens of the eye has been 150 mSv per year (about 15 rem). This figure reflects the level at which the risk of radiation-induced cataracts becomes a concern and gives workers a clear, manageable target for monitoring and shielding.

In this context, selecting 150 mSv as the limit makes sense because it directly protects the eye from cumulative damage while still allowing practical work. It’s worth noting that newer guidance has reduced the recommended limit to 20 mSv per year averaged over five years, with no single year exceeding 50 mSv, but many exam sources and older standards still cite the 150 mSv figure.