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The increase in background radiation due to these tests peaked in 1963 at about 0.15 mSv per year worldwide, or about 7% of average background dose from all sources. The Limited Test Ban Treaty of 1963 prohibited above-ground tests, thus by the year 2000 the worldwide dose from these tests has decreased to only 0.005 mSv per year. [35]
The definition of the BRET unit is apparently unstandardized, and depends on what value is used for the average annual background radiation dose, which varies greatly across time and location. The 2000 UNSCEAR estimate for worldwide average natural background radiation dose is 2.4 mSv (240 mrem), with a range from 1 to 13 mSv. A small area in ...
USA average medical and natural background Human internal radiation due to radon, varies with radon levels [8] 2 2 × 10 ^ 0: Acute-Head CT [7] 3 3 × 10 ^ 0: Annual: 0.34: USA average dose from all natural sources [6] 3.66 3.66 × 10 ^ 0: Annual: 0.42: USA average from all sources, including medical diagnostic radiation doses [citation needed ...
The worldwide average background dose for a human being is about 3.5 mSv per year , mostly from cosmic radiation and natural isotopes in the earth. The largest single source of radiation exposure to the general public is naturally occurring radon gas, which comprises approximately 55% of the annual background dose.
Background radiation is from naturally radioactive materials and cosmic radiation from space. [5] People are exposed to this radiation from the environment continuously, with an annual dose of about 3 mSv. [5] Radon gas is a radioactive chemical element that is the largest source of background radiation, about 2mSv per year. [17]
For purposes of comparison, the world average dose rate from naturally occurring sources of background radiation is 2.4 mSv per year, equal for practical purposes in this application to 2.4 mGy per year. [182] While there is some variation, most people (99%) received less than 7 mSv per year as background radiation. [186]
Small local populations, for example radiation workers, may not have a typical population profile. Both LNT and the concept of "collective dose" are criticized as speculative, lacking empirical evidence and based on unproved assumption that radiation "effect is cumulative over one’s lifetime, regardless of how low the rate of delivery of that ...
A unit sometimes used for low-level doses of radiation is the BRET (Background Radiation Equivalent Time). This is the number of days of an average person's background radiation exposure the dose is equivalent to. This unit is not standardized, and depends on the value used for the average background radiation dose.