What doses of radiation are dangerous to humans?

It is generally accepted that the man-made increase in the radiation background by an average of 1 mSv in one year and no more than 5 mSv in one year is considered acceptable for the population.
For the personnel of nuclear power plants and other enterprises associated with the possible exposure of people to ionizing radiation, in Russia, the maximum permissible dose of irradiation is 20 m3 per year on average for 5 years, but not more than 50 mSv per year.