There comes a point in time where you will most likely find yourself performing radiography, this article is written to help you remain safe
Radiation Protection and Dose Limitation
No radiation practice shall be justified until it produces a net positive benefit.
Doses received during radiation work should be as low as reasonably achievable.
The dose limit should not exceed prescribed limits.
This limit is put in place in order to prevent deterministic effects and limit probabilistic effects. As the deterministic effects have specific threshold values, they can be avoided by lowering the dose value below the threshold value. The probabilistic effects, on the other hand, don’t have any threshold value. Because of this, a certain amount of risk is always involved with radiation work proportional to the dose received.
It’s important to keep an accurate measurement of the radiation doses received by any personnel who happen to be working with radiation. This process is called personnel monitoring. Modern personnel monitoring systems use what are known as thermoluminescent dosimeter (TLD) badges, which are made of two or three TLD discs in a plastic cassette. When the radiation exposed disc is heated, it emits light photons and the flux of light photons is proportional to radiation dose received.
Area monitoring is the process of monitoring the radiation level at different locations around the radiography installation. This process is useful for checking the shielding adequacy and to evaluating the radiation protection system at the facility. The process uses gas base radiation detectors which are installed around the radiography room. The area is cordoned in case of field radiography. Ionization chambers can also be used, but they are bulky and sensitive to environmental conditions.
Radiation Hazard Control
The radiation hazard can be controlled by three fundamental parameters: time, distance, and shielding. Radiation levels for a point source vary inversely with the square of distance between the source and the point of measurement. For that reason, increasing the distance between the operator and the source is the most economical way of controlling the radiation intensity. The use of remote handling devices, such as gamma cameras and long cables between the tube head and control panel, are recommended for site applications.
Radiation Emergency Plan
Even when all the necessary precautions are taken, radiation accidents still occur. For this reason every organization using radiation should have an emergency preparedness plan to tackle unexpected circumstances. Emergency planning includes assessment of radiation hazards in accidental situations, procurement of radiation detection equipment for use in emergency situations, and proper classroom training to handle the emergency situation.
This post is based on an article from the November/December 2012 issue of Inspectioneering Journal by Sanjoy Das, D. Mukherjee and S. Anantharaman at the Bhabha Atomic Research Centre. You can find the original article here: https://inspectioneering.com/journal/2012-11-01/2840/radiation-safety-in-industrial