If you are traveling with a radiation monitor, it is recommended that you also bring a control monitor.
What should I do if I need to travel with my monitor?
PRMS guidelines state that monitors should not be taken off-site and should always be kept with the control monitor at the workplace when not in use. However, if you need to travel for work, we highly recommend taking a spare monitor with you to use specifically as a travel control monitor. This will allow you to measure the background radiation at your destination and during travel. The radiation dose recorded by the travel control monitor will be subtracted from your personal monitor by our lab to calculate your occupational dose. If you are travelling with a group to the same locations, you can use a single travel control monitor for the entire group. Please indicate which monitor was used as the travel control monitor when returning the used monitors.
How should a travel control monitor be used?
During transit and when not in use, it is important to keep your personal monitor and the travel control monitor together. When you reach your destination and start using your personal monitor, the control monitor should be stored in a location that accurately reflects the local background radiation. It should be kept away from any radioactive sources or radiation-generating equipment but avoid storing it in a shielded container. For additional guidance on storing a control monitor, please refer to our control monitor factsheet.
Why is travelling with a control monitor important?
When you travel for work, the background radiation level at your destination is likely to be different from that of your usual workplace. In Australia, the average annual background radiation is approximately 1.5 mSv, but this can vary greatly depending on the location. Internationally, background levels can be much higher. To ensure that your occupational dose assessments are accurate and dependable, it's essential to subtract the appropriate background radiation contribution recorded on the travel control monitor from your personal monitor.
What are potential sources of radiation during travel?
Potential sources of radiation during travel can include (but are not limited to):
- Differences in background radiation levels in different locations
- Higher levels of cosmic radiation when flying
- Certain types of baggage scanners
What happens if my monitor was scanned by a baggage scanner?
Older style X-ray baggage scanners give out a small amount of radiation and are unlikely to give workers a false occupational dose. For each pass of the baggage X-ray scanner there would be a maximum dose delivered of 0.01 mSv (Section 5.2(b) of Radiation Health Series 21). A monitor would have to pass through a baggage scanner more than 10 times to receive a dose greater than 0.1 mSv.
However, the newer CT-style baggage scanners, which allow you to keep your laptop in your bag, can deliver a higher dose of approximately 0.5 mSv per scan, depending on the scanner’s settings. This radiation is considered part of the monitor’s background radiation dose. That’s why it’s important for the control and personal monitors to stay together during travel, so that an accurate occupational dose can be determined by subtracting the background radiation.
To maintain the integrity of dose records of radiation workers who frequently require hand baggage security screening, monitors should not be scanned by X-ray-based scanners. Radiation workers should be permitted to carry the monitors on their person after declaring the possession of their monitor to security screening points and be checked by alternative screening processes.
To minimise the impact of baggage scanners on background dose, we advise carrying both the personal monitor and the travel control monitor with you during airport passenger screening. By keeping the monitors on your person, you can ensure that the background dose recorded on both devices remains consistent, while also minimising any additional background dose.
What if I wear my monitor when going through airport passenger screening?
The latest technologies for airport security screening are whole-body imaging machines that use millimetre-wave technology to scan an individual’s form. Millimetre waves are a form of non-ionising radiation, meaning they do not emit ionising radiation like X-rays. Therefore, passing through a whole-body machine in Australia will not expose the monitor to any radiation dose.
In some overseas airports, body scanners may use backscatter X-ray technology. These scanners apply very low levels of ionising radiation and measure the reflected X-rays from the person being screened. Typically, the radiation dose from these scanners is many times lower than that of medical X-rays. It is unlikely that these types of scanners would result in a measurable radiation dose to the monitor.
For an optimal approach, we recommend carrying both the personal monitor and the travel control monitor with you when undergoing passenger screening. This practice minimises the influence of baggage scanners on the background dose and ensures a consistent background dose reading on both devices.
Will air travel cause a false reading on my monitor?
Flying exposes you to more cosmic radiation than being on the ground. For people who don't fly frequently, the increase in exposure is very small and won't significantly add to the dose recorded on their monitor. For instance, a flight from Melbourne to London may result in a 0.065 mSv dose from cosmic radiation. Shorter flights will result in a lower dose. To ensure that this background dose is properly removed from your personal monitor, it's advisable to travel with a travel control monitor.