Committed effective dose equivalent

Occupational - the committed effective dose equivalent (Internal) and annual effective dose equivalent (external) combined... 

The ALI is the activity of a radionuclide that can be taken into the body in a year, by inhalation or ingestion, without exceeding a committed effective dose equivalent (CEDE) of 5 rem/year or a committed dose equivalent to any organ of 50 rem/year, whichever is more limiting. The total effective dose equivalent TEDE is the sum of the CEDE and any penetrating external dose (10 CFR 20). If any external dose is present the ALI must be reduced by a proportional amount to ensure that the dose limits are not exceeded. For example, if a worker received an external dose of 1 rem/year, the ALI would have to be reduced by 20% to ensure that the TEDE did not exceed 5 rem/year. 

The SITP is a quantity derived from the Annual Limit on Intake (ALI), an internationally accepted concept that has been acknowledged by the Government s Radioactive Waste Management Committee (RWMAC) as a valid method of establishing equivalent hazards of different waste types. The ALI is a derived limit for the permissible amount of radioactive material taken into the body of an adult radiation worker by inhalation or ingestion in a year. The ALI is the smaller value of intake of a given radionuclide in a year by the reference man that would result in either a committed effective dose equivalent of 0.05 Sv or 0.5 Sv to any individual organ or tissue. 

Total effective dose equivalent (TEDE) is the sum of the deep-dose equivalent (for external exposure) and the committed effective dose equivalent (for internal exposure). 

Derived intervention levels (DIL) are concentrations of radioactivity in food whose consumption would deliver a committed effective dose equivalent equal to the most limiting of the protection action guides (PAGs) developed by FDA (1998). 

Committed effective dose equivalent the sum, over all relevant tissues... 

By considering all possible transfer routes, one can estimate what amount of a radionuclide released to the environment may end up in plants, animals, or man. When these figures are combined with the dose conversion factors ("committed effective dose equivalent per unit intake", according to ICRP) in Table 18.12, it is possible to calculate the dose received by man from intake of a radionuclide in the environment. The dose conversion factors dep d on the mode of intake (usually only inhalation or ingestion). Thus... 

One remaining barrier to significant injury, electric shock (>50 volts AC), radiation exposure (one event >1000 mr uptake, intake or Committed Effective Dose Equivalent [CEDE]) or Industrial Hygience Exposure (>3 times OSHA limits), exceed criticality limit or double contingency is not maintained... 

Dose limits means the permissible upper bounds of radiation doses. These are usually set for a calendar year. They apply to the dose equivalent received during the set interval, the committed effective dose equivalent resulting from the intake of radioactive material during the interval or the effective dose equivalent received in 1 year The external dose and the internal dose must be combined so as not to exceed the permissible limits. The following equation can be used to compute the relative amounts of each, for the annual intake Ij of nuclide J ... 

A committed effective dose equivalent or total effective dose equivalent to any member of the public no greater than 4 mrem may result annually from exposure to and consumption of groundwater contaminated by releases from an LLRW disposal facility. 

At present, the Dq>artment of Energy internal standards require that sites be remediated to an annual committed effective dose equivalent not to exceed 1 mSv per year to a maximally exposed individual, plus a requirement that the potential exposure be As Low As Reasonably Achievable (ALARA). An analysis of previous remedial actions reveals that, in many cases, the actual committed effective dose equivalent is less than 0.01 mSv per year following remediation. 

This means that if a radionuclide is inhaled that produces a 49 rem CDE to the thyroid, an additional whole body exposure of only 1 rem can be allowed in that year. If a CDE of 45 rem or less is attained in an organ, the 5 rem per year whole body exposure still stands. The same addition of internal and external dose applies to whole body exposure if the committed effective dose equivalent (whole body effect of internal dose) is 4 rem, whole body external dose would be limited to 1 rem.)... 

Note that the dose equivalents for extremities (hand and forearms, feet and lower legs), skin, and lens of the eye are not considered in computing the committed effective dose equivalent, but are subject to limits that must be met separately. 

The Total Effective Dose Equivalent (TEDE) is defined as the sum of the deep-dose equivalent and the Committed Effective Dose Equivalent (CEDE). The deep-dose equivalent is related to ... 

In the BSS [2] and in the 1990 Recommendations of the ICRP [6], the approach to calculating the committed effective dose is based on that used for the calculation of committed effective dose equivalent, although as a result of improved information on the late effects of radiation on the tissues of the body some changes have been made to the values of tissue weighting factors and a greater munber of tissues now have specified weighting factors (see Table A-in). 

Throughout this book the term dose is used to denote the sum of the effective dose equivalent resulting from external exposure during one year and the committed effective dose equivalent from that year s intake of radionuclides. 

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