Definitions for **"Sievert"**

Sievert (Sv) is the SI derived unit of dose equivalent when the absorbed dose of ionizing radiation multiplied by the stipulated dimensionless factors is 1 J/kg. It is named after the Swedish physicst Rolf Sievert (1896-1966).

1 Sievert equals 100 rem. Abbreviation is Sv.

The quantity obtained by multiplying the equivalent dose to various tissues and organs by a weighting factor appropriate to each and summing the products. Unit sievert, symbol Sv. Frequently abbreviated to dose. (see also Micros, Mills, Megas and Measurements)

The modern unit of radiation does, incorporating quality factors for the biological effectiveness of different types of ionizing radiation (implying that alpha particles are 20 times more dangerous than X-rays depositing the same amount of energy in tissues). See; Ionizing Radiation.

The special name of a biological unit of dose.

The international unit of radiation equivalent dose and effective dose. The equivalent dose in sieverts is numerically equal to the absorbed dose in gray multiplied by a quality factor. One sievert is equivalent to 100 rems (the traditional unit).

A measure of radiation dose which takes into account the type of radiation involved, the energy deposited in the tissues irradiated, and the sensitivity of the different body tissues to radiation. Typically, doses are expressed in terms of micro sieverts (µSv). 1 sievert = 1 million µSv. A dose of around 6.5 Sv, delivered over a few minutes or hours, will lead to death from acute radiation sickness within a few weeks. The annual average dose to an individual in the United Kingdom is 2,200 µSv from natural radiation and 400 µSv from man-made radiation, (of which 370 µSv is from medical uses of radiation and radioactive materials).

an SI unit used for measuring the effective (or "equivalent") dose of radiation received by a human or some other living organism. Various kinds of radiation have different effects on living tissue, so a simple measurement of dose as energy received, stated in grays or rads, does not give a clear indication of the probable biological effects of the radiation. The equivalent dose, in sieverts, is equal to the actual dose, in grays, multiplied by a "quality factor" which is larger for more dangerous forms of radiation. An effective dose of one sievert requires 1 gray of beta or gamma radiation but only 0.05 gray of alpha radiation or 0.1 gray of neutron radiation. One sievert equals 100 rem. The sievert is a large unit, so radiation doses are often measured in millisieverts (mSv). The unit honors the Swedish physicist Rolf Sievert (1898-1966), who worked over many years to measure and standardize the radiation doses used in cancer treatment.

3/4 The SI unit of dose equivalent. 1 Sv = 1 J/kg.

The unit for the dose equivalent of ionising radiation received by a person. The abbreviation is Sv. A dose of 1 Sv is very high. The maximum annual permitted dose level (PDL) for the average person (i.e. one not working with ionising radiation) is just 5mSv - the average dose is about 2mSv.

The SI unit of absorbed dose defined as the number of grays times a quality factor. The sievert represents a dose equivalent or a dose that is correlated with injury due to radiation exposure. Symbol: Sv. Related to gray. Related to quality factor. Related to roentgen equivalent man. Reference: NUREG-0544, Rev. 4.

A unit of radiation dose, equal to the dose delivered by a point source of 1 milligram of radium, enclosed in a platinum container with walls 1/2-millimeter thick, to a sample at a distance of 1 centimeter over a period of 1 hour. 1 sievert = 100 rem.

a derived unit that attempts to express an equivalence of absorbed dosage taking into account biological harm

The unit of radiation dose measurement. Two and a half Millisieverts is the national average dose from background radiation from all sources. (1,000 Millisieverts = 1 Sievert).

a unit used to derive a quantity called dose equivalent. This relates the absorbed dose in human tissue to the effective biological damage of the radiation. Not all radiation has the same biological effect, even for the same amount of absorbed dose. Dose equivalent is often expressed as millionths of a sievert, or micro-sieverts (µSv). One sievert is equivalent to 100 rem. For more information, see " Primer on Radiation Measurement" at the end of this document.

A unit of measure of radiation dose equivalent. It is equal to dose in grays multiplied by certain modifying factors. I sievert=100 rem.

The SI unit for dose equivalent. It is gradually replacing the rem. 1 rem = 0.01 Sv.

The SI unit of dose equivalent equal to 1 Joule/kilogram.

unit of radiation dose equivalent; 100 rem = 1 Sv.

The international unit (SI) of dose equivalent (DE, human exposure unit), which is equal to 100 rem. It is obtained by multiplying the number of grays by the quality factor, distribution factor, and any other necessary modifying factors.

The SI unit of absorbed dose equivalent (1 Joule/Kilogram or 100 rems).

The metric unit of dose equivalent (biological effect) of radiation to humans. 1 Sievert = 100 rem.

The sievert is a measure of the biological effectiveness of radiation. For X-rays and gamma rays, 1Sv coresponds to the deposition of 1 joule of energy per kilogram of material. Strictly speaking, this unit should only be used when discussing delayed effects. The appropriate unit for early effects is the gray.

SI unit of equivalent dose or effective dose. 1 Sv = 100 rem.

The international standard unit of measurement of effective dose, dose being the the amount of energy delivered to a mass of material by ionising radiation passing through it. The average person receives a dose of approximately 1.5 milliSieverts of background radiation each year. For more information on radiation doses, click here (PDF 253 Kb).

A measure of dose (technically, dose equivalent) deposited in body tissue, averaged over the body. Such a dose would be caused by an exposure imparted by ionizing x-ray or gamma radiation undergoing an energy loss of 1 joule per kilogram of body tissue (l gray). One sievert is equivalent to 100 rem.

The international unit of dose equivalent, measuring the effect of radiation dose on persons. Commonly used subunits are the milli-Sievert (one thousandth) and the micro-Sievert (one millionth).

The SI unit of dose equivalent; 1 Sv = 100 rem.

Unit of equivalent absorbed dose equal to 100 rems.

Standard international unit of any of the quantities expressed as dose equivalent. The dose equivalent in sieverts is equal to the absorbed dose in grays multiplied by the radiation weighting factor (1 Sv=100 rems).

A unit of dose equivalent. 1 Sv= 100 roentgens, 10 µSv/hr = 1 milliroentgen/hr. (µSv micro-Sievert, micro is one millionth, milli is one thousandth.)

Unit indicating the biological damage caused by radiation. One Joule of beta or gamma radiation absorbed per kilogram of tissue has 1 Sv of biological effect; 1 J/kg of alpha radiation has 20 Sv effect and 1 J/kg of neutrons has 10 Sv effect.

the newer, international unit of measurement of radiation exposure. One sievert equals 100 rem. Often reported in millisieverts (mSv), which are thousandths of a sievert. A mSv is 1/10 of a rem. See also rem.

is the SI unit of any of the quantities expressed as dose equivalent. The dose equivalent in sieverts is equal to the absorbed dose in grays multiplied by the quality factor (1 Sv=100 rems).

See effective dose.

The international unit of dose equivalent. The dose equivalent in sieverts is equal to the absorbed dose in grays (see gray above) multiplied by the radiation weighting factor and tissue weighting factors. One Sv = 100 rem.

Radiation dose measured in Sieverts (Sv) millisieverts (mSv), or microsieverts (µSv). 1 Sv = 1000mSv, 1 mSv = 1000 µSv. These units take into account the type of radiation involved, its effect on the body's tissue, and the sensitivity of the different body organs to radiation

The sievert (symbol: Sv) is the SI derived unit of dose equivalent. It attempts to reflect the biological effects of radiation as opposed to the physical aspects, which are characterised by the absorbed dose, measured in grays. It is named after Rolf Sievert, a Swedish medical physicist famous for work on radiation dosage measurement and research into the biological effects of radiation.