Problem: Industrial Hygiene and Ergonomics
Case Study:
What happens when medical workers are exposed to radiation? KUALA LUMPUR (Bernama): Human beings are on a daily basis exposed to background radiation directly or indirectly coming from cosmic rays, mobile phones, television sets, building materials, agricultural produce, and even their own bodies. The health risks posed by exposure to certain types of radiation are well known, medical science has long proven the benefits of radiation in the field of diagnostic imaging such as radiography, computed tomography (CT), mammography, radiotherapy and nuclear medicine. The application of radiation is particularly useful for cancer detection and treatment, as diagnostic tools allow medical experts to determine the exact location of tumours while treatments such as radiotherapy are used to kill the cancerous cells. A pertinent issue that arises here is occupational radiation exposure and its health effects on interventional medical workers - and to what extent they are protected considering the fact that they handle hundreds of patients every day who have to undergo radiography, CT scans, radiotherapy or fluoroscopic procedures for diagnostic and treatment purposes.
According to radiation protection officer at Hospital Ampang's Radiology Department Mohammad Azwin Abdul Karim, one of the major challenges faced by the hospital in radiation safety is creating a protected environment for the staff handling radiation equipment. Radiation safety refers to protecting workers from the harmful effects of radiation by taking the necessary measures to reduce unnecessary exposure. "What concerns us is the scattered radiation that can arise from the rays penetrating the patient's body, which the staff handling the radiation machine are exposed to, " he said. Azwin said the radiation protection system is in general governed by three basic principles: justification, optimisation of protection, and dose limit. "Optimisation of protection should be given top priority by ensuring exposure to radiation is as dose as low as reasonably achievable, " he said.
Reducing the period of time spent near the radiation source, increasing the distance from the radiation source, and using appropriate protective gear can indirectly reduce the radiation dose workers are exposed to, he added. Impact of radiation on staff Although medical workers are not directly exposed to radiation, its effects are known to have a short-term and long-term impact on their health and can affect their quality of life and even that of their offspring. Azwin said the biological effects of radiation can be classified as deterministic and stochastic effects. Deterministic effects are evident when an individual is exposed to radiation exceeding the threshold point.
The higher the dose, the worse the effects suffered by the victim, including cataracts, skin injury and hair loss. Stochastic effects can likely appear irrespective of the amount of radiation dose received by an individual and can lead to cancer and genetic damage. In view of its harmful effects, improvements have been made in terms of radiation protection, including providing radiation workers with personal protective gear made of lead, which is a good material for radiation shielding. All radiation staff must now wear protective gear such as an apron, thyroid shield, lead cap and lead goggles that were designed to protect their bodies from exposure to radiation. He said under Regulation 8 of the Atomic Energy Licensing Regulations (Basic Safety Radiation Protection) 2010, the limit on the effective radiation dose for a worker shall be 20 millisieverts (mSv) in a calendar year.
Azwin added that it is also compulsory for staff to go for periodic health checks to detect any effect of radiation due to workplace exposure. Rooms with a view on safety Medical imaging rooms in hospitals where radiation equipment is installed must also conform to strict guidelines and standards. The building structure of the room or space where radiation services are provided in a hospital or health centre has to meet the required minimum standards to minimise the incidence of scattered radiation. As for staff, in order to monitor their level of exposure to radiation, it is compulsory for them to wear personal radiation monitoring devices such as the radio photoluminescence dosimeter, optical stimulated luminescence dosimeter and thermoluminescence dosimeter. Malaysian Nuclear Agency director-general Dr Siti A'iasah Hashim, meanwhile, said it is crucial for them to wear such monitoring devices due to the characteristics of radiated particles as they are invisible, odourless and tasteless.
Safety precautions Siti A'iasah said in Malaysia, the Atomic Energy Licensing Act 1984 provides for strict regulation and control of atomic energy. The Act also requires workers likely to be exposed to radiation to wear approved personnel-monitoring devices, to keep records of dose and type of radiation the worker is likely to be exposed to, to install or use monitoring devices at the workplace to record the amount of radiation present, and to undergo regular medical examinations.
Task
According to the above case, analyze how radiation exposure affects the health of medical workers in the short and long term. Why does it need optimization of protection?