During radiographic non destructive testing, harmful radiation particles are used to gather insight into the internal structure of test objects, like casings and welds. X-Rays and gamma radiation are exceptionally useful in determining when components or structures need to be replaced or repaired, however are also very dangerous if they come into contact with organic tissue. During radiographic NDT, industrial radiography exposure devices use sources of radiation as a fundamental part of their operation. Safety compliance therefore must be complied with to ensure the risk of developing cancer is completely minimised for all NDT workers.
What Are The Dangers of Radiation?
When radiation passes through living cells it transfers some of its energy to the atoms which make up these cells. This can lead to chemical changes which cause cell modification or cell death. Somatic or hereditary mutations can occur following cell modification and, as mentioned, can cause cancer or other abnormality in the person who has been exposed to radiation or such person’s progeny, respectively.
How To Prevent Radiation Affecting NDT Workers?
The primary concern of NDT workers using radiographic non destructive testing methods is to cordon off a safe area around the site the radioactive particles are applied. The goal of this strategy is to prevent members of the public breaching the area where radioactive particles are active. This can be achieved with use of hard or soft barricades, warning lights and warning signs.
The formula for calculating the distance of the cordoned off area is d = √(WUT)/P.
In this equation, d stands for distance, W stands for workload, which is equal to dose rate x present activity of your source x working hours in a week. U is equal to 1, T is equal to the occupancy factor around the site, where a full site is equal to 1 and P is equal to the permissible dose of radiation which may be absorbed by a member of the public (2mR/wk).
Best practice is to cordon off the area around the site of radiographic NDT where a meter shows a 0.0mR rating.
Workers using radiographic NDT equipment should always wear the appropriate PPE too, to prevent harm befalling them. A lead apron, along with lead glass mask, a thyroid shield and goggles must be worn at all times during operation of radiographic NDT equipment. At the end of the day, anybody who is not unequivocally required to be on-site should stand outside the cordoned off zone.
Contact NDT Australia
If you are looking for radiographic non-destructive testing equipment, check out NDT Australia’s online store. We supply a range of NDT technology, including particle testing, radiographic and ultrasonic non-destructive testing equipment. We are open for business Monday to Friday, 7:30am to 4:00pm. Contact our friendly sales team on (02) 9524 0558 to ask any questions or to place an order for any of the products listed on our online store.