Final answer:
A hospital employee who reaches the radiation exposure limit must cease working for a while to prevent health risks such as cancer or genetic defects. Work involving medical imaging, nuclear medicine, and tasks at nuclear facilities are susceptible to increased radiation exposure. Understanding individual exposure compared to occupational limits can highlight potential health risks.
Step-by-step explanation:
Once a hospital employee reaches the limit for radiation exposure, he or she must stop working for a time. This is to prevent any additional exposure that could increase the risk of health effects, such as cancer or genetic defects. Occupational exposure to radiation is monitored closely, and limits are set to protect workers. Comparing the annual exposure rate of an individual to the present maximum allowed for radiation workers can provide insight into the level of risk involved.
Types of work that are likely to cause an increase in radiation exposure include medical imaging, nuclear medicine, and radiation therapy roles in healthcare, as well as jobs at nuclear power plants and certain industrial applications. Workers in these fields may encounter both planned and unplanned exposure scenarios.
The long-term effects of radiation, such as cancer and genetic defects, arise from the disruption of cellular processes. A lower lifetime risk from lower doses (e.g., 0.03 percent from 1 rem) cannot be easily detected demographically, but higher doses (such as the 1 Sv received by Hiroshima and Nagasaki survivors) present a more observable 3 percent risk of cancer.
An example of an occupational exposure is a plumber at a nuclear power plant who received a dose of 30 mSv in 15 minutes; such instances would contribute to the worker's annual exposure and could potentially increase the risk of radiation-induced health effects. The risk of cancer is assumed to be proportional to exposure, based on the linear hypothesis, while the genetic effects of radiation have varying models depending on the organism studied, suggesting that more research is needed to fully understand these risks in humans.