Reply #34: 1,000 millisieverts per hour = 1 sievert per hour! Use the smaller number to make it look like no [View All]

[sce56]

big deal! 1 Sievert is DEADLY!
http://en.wikipedia.org/wiki/Sievert
The unit gray measures absorbed radiation which is absorbed into any material. The unit sievert specifically measures absorbed radiation which is absorbed by a person. The equivalent dose to a person is found by multiplying the absorbed dose, in gray, by a weighting factor (w). The weighting factor (sometimes referred to as a quality factor) is determined by a combination of: the radiation type, the tissue absorbing the radiation, and other pertinent factors.<1>

In terms of SI base units:

1 Sv = 1 Gy • w (where Sv=sievert, Gy=gray, w=weighting factor specific to each type of radiation and tissue).
big deal!


1 Gy = 1 J / kg of absorbing material
therefore:

1 Sv = 1 J / kg of absorbing material • w


Dose examples Single dose examplesDental radiography: 0.005 mSv<4>
Average dose to people living within 16 km of Three Mile Island accident: 0.08 mSv during the accident<5>; maximum acceptable dose for the public: 1 mSv/year<6>
Mammogram: 3 mSv<4>
Brain CT scan: 0.8–5 mSv<7>
Chest CT scan: 6–18 mSv<7>
Gastrointestinal series X-ray investigation: 14 mSv<8>
International Commission on Radiological Protection recommended limit for volunteers averting major nuclear escalation: 500 mSv<9>
International Commission on Radiological Protection recommended limit for volunteers rescuing lives or preventing serious injuries: 1000 mSv<9>
Hourly dose examplesAverage individual background radiation dose: 0.23μSv/hr (0.00023mSv/hr); 0.17μSv/hr for Australians, 0.34μSv/hr for Americans<10><5><11>
Highest reported level during Fukushima accident: 1000 mSv/hr reported as the level at a pool of water in the turbine room of reactor two.<12><13><14>
Yearly dose examplesLiving near a nuclear power station: 0.0001–0.01 mSv/year<8><10>
Living near a coal power station: 0.0003 mSv/year<10>
Sleeping next to a human for 8 hours every night: 0.02 mSv/yr<10>
Cosmic radiation (from sky) at sea level: 0.24 mSv/year<8>
Terrestrial radiation (from ground): 0.28 mSv/year<8>
Natural radiation in the human body: 0.40 mSv/year<8>
Radiation produced by the granite of the United States Capitol building: 0.85 mSv/year<15>
Average individual background radiation dose: 2 mSv/year; 1.5 mSv/year for Australians, 3.0 mSv/year for Americans<10><5><11>
Atmospheric sources (mostly radon): 2 mSv/year<8><16>
Total average radiation dose for Americans: 6.2 mSv/year<17>
New York-Tokyo flights for airline crew: 9 mSv/year<11>
Smoking 1.5 packs/day: 13-60 mSv/year<15><16>
Current average limit for nuclear workers: 20 mSv/year<11>
Background radiation in parts of Iran, India and Europe: 50 mSv/year<11>
Elevated annual regulatory limit for workers during Fukushima emergency: 250 mSv/year<18>
Dose limit examples Criterion for relocation after Chernobyl disaster: 350 mSv/lifetime<11>
In most countries the current maximum permissible dose to radiation workers is 20 mSv per year averaged over five years, with a maximum of 50 mSv in any one year. This is over and above background exposure, and excludes medical exposure. The value originates from the International Commission on Radiological Protection (ICRP), and is coupled with the requirement to keep exposure as low as reasonably achievable (ALARA) – taking into account social and economic factors.<19>
Public dose limits for exposure from uranium mining or nuclear plants are usually set at 1 mSv/yr above background.<19>
Symptom benchmarksSymptoms of acute radiation (dose received within one day):<20>

0 – 0.25 Sv (0 – 250 mSv): None
0.25 – 1 Sv (250 – 1000 mSv): Some people feel nausea and loss of appetite; bone marrow, lymph nodes, spleen damaged.
1 – 3 Sv (1000 – 3000 mSv): Mild to severe nausea, loss of appetite, infection; more severe bone marrow, lymph node, spleen damage; recovery probable, not assured.
3 – 6 Sv (3000 – 6000 mSv): Severe nausea, loss of appetite; hemorrhaging, infection, diarrhea, peeling of skin, sterility; death if untreated.
6 – 10 Sv (6000 – 10000 mSv): Above symptoms plus central nervous system impairment; death expected.
Above 10 Sv (10000 mSv): Incapacitation and death.
See also Radiation poisoning.