If you are travelling 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
- monitors should always be kept with the control monitor at the workplace when not in use.
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. On average, Australians are exposed to 1.7 mSv of radiation per year from natural sources. Internationally, background levels can be much higher. By keeping the control monitor with the personal monitor, dose assessments are more accurate and dependable.
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.
Newer CT-style baggage scanners, which allow you to keep your laptop in your bag, can deliver a higher dose of about 0.5 mSv per scan, depending on the scanner settings. This radiation counts as part of the monitor’s background radiation dose. That’s why it’s important to keep both the control and personal monitors together during travel. This ensures that the background radiation can be subtracted properly to calculate an accurate occupational dose.
To maintain accurate radiation records for workers who frequently go through hand baggage screening, their monitors should not be scanned by X-ray scanners. Instead, radiation workers should be allowed to carry their monitors with them and declare them to security. They can then go through alternative screening methods.
To reduce the impact of baggage scanners on background dose, we recommend keeping both your personal monitor and travel control monitor with you during airport screening. This ensures both devices record the same background radiation and helps avoid any additional exposure.
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.
We recommend carrying both the personal monitor and the travel control monitor with you when undergoing passenger screening. This will minimise the impact of baggage scanners on the background dose and ensure 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.
Further information
Flying and health: Cosmic radiation exposure for casual flyers and aircrew | ARPANSA
Airport passenger screening and health | ARPANSA
Statement on wearable personal dosimetry and X-ray security scanners | ARPANSA
