BRET units are used as a measure of low level radiation exposure. The health hazards of low doses of ionizing radiation are unknown and controversial, because the effects, mainly cancer and genetic damage, take many years to appear, and the incidence due to radiation exposure can't be statistically separated from the many other causes of these diseases. The purpose of the BRET measure is to allow a low level dose to be easily compared with a universal yardstick: the average dose of background radiation, mostly from natural sources, that every human unavoidably receives during daily life. Background radiation level is widely used in radiological health fields as a standard for setting exposure limits.[1] Presumably, a dose of radiation which is equivalent to what a person would receive in a few days of ordinary life will not increase his rate of disease measurably.
Definition
The BRET is the creation of Professor J R Cameron.[2] The BRET value corresponding to a dose of radiation is the number of days of average natural background dose it is equivalent to. It is calculated from the equivalent dose in sieverts by dividing by the average annual background radiation dose in Sv, and multiplying by 365:
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 India as high as 30 mSv (3 rem).[3][4] Using the 2.4 mSv value each BRET unit equals 6.6 μSv.
BRET values for diagnostic radiography procedures range from 2 BRET for a dentalx-ray to around 400 for a barium enema study.
background, radiation, equivalent, time, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sources, news, newspapers, books, sc. This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Background radiation equivalent time news newspapers books scholar JSTOR April 2011 Learn how and when to remove this template message Background radiation equivalent time BRET or background equivalent radiation time BERT is a unit of measurement of ionizing radiation dosage amounting to one day worth of average human exposure to background radiation BRET units are used as a measure of low level radiation exposure The health hazards of low doses of ionizing radiation are unknown and controversial because the effects mainly cancer and genetic damage take many years to appear and the incidence due to radiation exposure can t be statistically separated from the many other causes of these diseases The purpose of the BRET measure is to allow a low level dose to be easily compared with a universal yardstick the average dose of background radiation mostly from natural sources that every human unavoidably receives during daily life Background radiation level is widely used in radiological health fields as a standard for setting exposure limits 1 Presumably a dose of radiation which is equivalent to what a person would receive in a few days of ordinary life will not increase his rate of disease measurably Definition EditThe BRET is the creation of Professor J R Cameron 2 The BRET value corresponding to a dose of radiation is the number of days of average natural background dose it is equivalent to It is calculated from the equivalent dose in sieverts by dividing by the average annual background radiation dose in Sv and multiplying by 365 B R E T S V d o s e S V b a c k g r o u n d 365 displaystyle BRET frac SV dose SV background cdot 365 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 India as high as 30 mSv 3 rem 3 4 Using the 2 4 mSv value each BRET unit equals 6 6 mSv BRET values for diagnostic radiography procedures range from 2 BRET for a dental x ray to around 400 for a barium enema study See also EditBackground radiation Banana equivalent dose Flight time equivalent dose RadiologyReferences Edit Radiation Dose Descriptors BERT COD DAP and Other Strange Creatures1 Archived from the original on 2013 04 12 Retrieved 2013 03 13 http www chiropractic uk co uk gfx uploads textbox Members 20area Xray 20guidelines BERT 20table 20reference pdf bare URL PDF Background Radiation Natural versus Man Made Washington Stet Department of Health Monazite sand does not cause excess cancer incidence The Hindu WayBack archive https web archive org web 20060105033541 http www radiationcontrol utah gov XRAY BRET HTM Retrieved from https en wikipedia org w index php title Background radiation equivalent time amp oldid 1106282952, wikipedia, wiki, book, books, library,
