Table 1.

Sources of environmental radiation.⁷

Source	Exposure (mSv)
Airport scannerAir travel:	0.005 per exposure0.005 per short flight*0.03 per long flight*
Aircrew/frequent flyers	1–5 per year
Background radiation
• UK or Australia	1.8 per year
• USA	6.2 per year
• Kerala, India	30 per year
• Some areas of Brazil and Sudan	40 per year
• Ramsar in Iran	Up to 260 per year
Uranium miners/ nuclear industry workers	Additional to background: 1.5–2.5 per year

The unit mSv refer to exposure whilst the absorbed dose is measured in mGy.*At higher latitudes, multiply by a factor of 2--3.