Summary
Industrial radiography workers must be trained in the correct use of industrial radiography equipment. Not following procedures, a lack of awareness and not setting-up the controlled area properly may result in over exposure to high levels of ionising radiation.
What do I need to know?
Manufacturers, and inspection and testing services use a non-destructive method called industrial radiography to check for cracks or flaws in materials. There are two types of industrial radiography equipment, those using radiation generators and those using sealed radioactive sources. Industrial radiographs are performed in fully enclosed sites, partially enclosed sites, or open sites. Industrial radiography equipment can deliver large amounts of radiation in a short time. If the safety procedures are not followed, there is inadequate training and supervision, or a failure in the equipment, then it is possible that operators and other workers can be exposed to significant radiological health hazards including potentially lethal doses.
What is the possible exposure?
The main source of exposure for industrial radiography is by external exposure from the equipment’s source. Once the equipment or source of radiation is removed, the exposure stops.
External exposure from radiation generators or sealed radioactive sources that emit X-rays or gamma rays can interact with your body that may result in health effects that could result in serious injuries.
Internal exposure from sealed radioactive sources due to ingestion or inhalation under normal operating conditions is unlikely. However as these sealed radiation sources age there may be leakage of radioactive material creating a pathway for intake into the body. Good inspection and maintenance practices are essential to ensure industrial radiography equipment remain safe to use.
There is no potential for internal exposure from devices using radiation generators.
What are the possible health effects?
| Dose range (millisieverts) | Description | Possible health effects |
|---|---|---|
| Up to 10 | Very low dose | None observed or expected (typical background range) |
| 10–100 | Low dose | Plausible health effects but not observed |
| 100–1000 | Moderate dose | Increase risk of cancer Acute effects at higher end of range (above 500 mSv) |
| Above 1000 | High dose | Acute effects (burns, vomiting) Death possible at very high doses (above 5000 mSv) |
No health effects have been observed or are expected to be observed at the very low doses normally received in this occupation.
Ionising radiation has been proven to cause harmful short term effects at moderate and high doses received in short periods of time, above 500 mSv, with an increased risk of cancer shown to occur for long term exposures of above 100 mSv.
Moderate and high dose can occur in industrial radiography incidents. With relevant controls in place the risk from normal exposures are very low and comparable with the risks of exposure from background and medical radiation exposure.
In Australia most workers receive very low dose, however there have been incidents that have resulted in severe radiation health effects. These incidents have been caused by one or more for the following factors; human error, equipment failure, or organisation factors.
Case study: Accidental exposure of two radiographers1
The incident was caused by human error and interchangeable control panels. When more than one team is working simultaneous in the same area coordination is essential.
Two radiography teams were operating at opposite ends of a large workshop. Team A took longer to set up than team B. Both teams X-ray control panels and warning systems were in the middle of the workshop out of sight of the teams. Unfortunately team B completed the set up before team A and connected their control panel to team’s B X-ray tube and commenced an exposure and left the area. After the exposure was completed team B realised the control panel was connected to team A’s X-ray tube who were still setting up. Team A’s dosimeter measured a doses of 18 mSv and 39 mSv. However investigation of the incident revealed the estimated doses received would be 160 mSv and 600 mSv. Team A’s dosimeter underestimated the dose because team A had their backs to the X-ray generator and their dosimeters were shielded by their bodies.
Who is responsible for your safety?
In Australia the use of irradiating apparatus and radiation sources is regulated. Each state and territory is responsible for enforcing their respective radiation safety act and regulations in their jurisdictions. The Australian government is responsible of enforcing the radiation safety act and regulations of commonwealth entities only.
Organisations/employers are responsible for:
- devising, implementing, and regularly reviewing their radiation management plan
- regulatory compliance
- induction and ongoing training of workers, including contractors.
Workers are responsible for:
- following radiation protection practices specified in the radiation management plan
- complying with legitimate instructions of the employer or designated radiation safety officer
- participate in radiation protection training.
What are dose limits?
All Australian jurisdictions have uniform annual limits for public and occupational exposure to ionising radiation: 1 mSv for the public and 20 mSv for workers who are occupationally exposed. Despite this, there are different definitions of who is ‘occupationally exposed’ and who should wear personal dosimeters. You can further discuss occupational radiation exposure with your facility’s Radiation Safety Officer or the relevant jurisdictional regulator.
For a pregnant radiation worker, the dose to the unborn child is restricted to the same as a member of the public – 1mSv. (See Management of Pregnant Workers Exposed to Ionising Radiation factsheet)
