Radiation has created immense breakthroughs in both clinical and research applications, such as X-rays machines, CT scan, nuclear medicine. Problems arise with unsupervised and careless use of radiation which can create potentially hazardous situations for both the patients as well as the personnel who work at a hospital.
There are various regulatory bodies at the international and national level, which lay down norms for radiation protection. These are the International Commission for Radiation Protection (ICRP) the National Commission for Radiation Protection (NCRP) in America, and the Atomic Energy Regulatory Board (AERB) in India. These bodies recommend and regulate the site specifications for installation of various equipment used in medical imaging as well as recommend the safe limits of occupational radiation exposure for both the general public and radiation. The implementation of these norms are however conducted on a day to day basis at micro level at each hospital or centre harbouring such equipments by a team of specialists who look at maintaining adequate radiation protection measures. Such a team of specialists from different disciplines is often headed by the Radiation Safety Officer (RSO). The RSO serves as a liason between the radiation protection committee of a hospital and the regulatory bodies and is responsible for maintaining adequate radiation surveillance and radiation safety.
What is radiation safety?
Protection against harmful effects of ionising radiation by taking steps to ensure that people will not receive its excessive dose by monitoring all sources of radiation to which they may be exposed. There are two ways of getting contaminated by radioactive material-
External contamination: Occurs when radioactive material, in the form of dust, powder or liquid, comes into contact with a person’s skin, hair or clothing. In other words, the contact is external to the human body. One can become internally contaminated if radioactive material gets into the system.
Internal contamination: Occurs when people swallow, breathe-in or an open wound on the skin absorbs radioactive material. Some types of radioactive material stay in the body and are deposited in different organs. A few are eliminated from the body through sweat, urine and faeces.
That is why strict radiation safety should be followed within the hospitals and all possible radiation prone areas.
The basic principle of radiation protection in hospitals
The maximum use of radiation material with the highest number of people being exposed to radiation knowingly or unknowingly is at hospitals. Every hospital needs to establish a committee which will look after the norms and actions to measure the level of radiation. The team should see to it that all guidelines are followed. A status report needs to be submitted to the regulatory bodies on a regular basis.
The guiding principle of radiation protection is to keep radiation exposure ‘As Low As Reasonable Achievable’- (ALARA). To follow this principle it is essential that the use of radiation be both justified and optimised. A simple guide to reduce radiation exposure from a radiation source is to follow the time-distance and shielding principles
Time: The exposure time is related to radiation exposure and exposure rate. If the exposure time is kept to the minimum, then dose to the individual is small.
Distance: The second radiation protection action is related to distance between the source of radiation and the exposed individual. Exposure to an individual decreases inversely as the square of the distance.
Shielding: The third radiation protection action related to shielding. Shielding implies that certain materials will attenuate radiation when they are place between the source of radiation and the exposed individual, for instance lead is a good shielding material and lead aprons are often worn by the radiation workers to reduce their radiation exposure.
Every individual around the radio active area is prone to some kind of exposure. Safe use of hazardous materials in the workplace demands cooperation of individuals who have technical knowledge/ training specific to their application, follow administrative and technical procedures established to ensure a safe and orderly workplace.
It is compulsory for the staff to wear a dosimeter. Data from the dosimeter is reliable only if it is properly clocked and returned within the specified time. No matter what source of radiation one works with, an effective way to enhance safety is to allow access only to those with business in the area.
Places where radiation in hospitals are extreme-
Nuclear medicine department, Radiotherapy department, Radiology department
The use of radiation in medicine has brought in a lot of benefits to both clinical and research applications. The use of radiation in medicine is expected to keep rising, since benefits to patients are great and technologies gain wider use. It is however essential that the radiation exposures be optimized. Newer developments in equipments are being done every day not just to reduce the radiation exposures of the radiation workers but also for patient undergoing these procedures. The use of technologies not using radiation such as MRI and ultrasound is also rising which can give similar information at places without the radiation exposure. However there is a long way to go before the use of radiation can be totally done away with in medicine. The use of radiation today saves millions of lives. The safe use of radiation is however paramount and can be achieved only by the concerted and collaborative efforts of the regulatory bodies, the doctors, the radiation professionals, equipment manufacturers and all others involved in the use of radiation in medicine.