|
 |
| NEWS |
|
| Year : 2011 | Volume
: 34
| Issue : 2 | Page : 147 |
|
|
News and Information
Pushparaja
Ex. RSSD, BARC
| Date of Web Publication | 12-Jul-2012 |
Correspondence Address:
Pushparaja
Ex. RSSD, BARC
 Source of Support: None, Conflict of Interest: None  | Check |
How to cite this article:
Pushparaja. News and Information. Radiat Prot Environ 2011;34:147 |
Latest Publication from ICRP
Conversion Coefficients for Radiological Protection Quantities for External Radiation Exposures, ICRP Publication 116, Ann. ICRP 40(2-5), 2010
The above publication gives fluence to dose conversion coefficients for both effective dose and organ absorbed doses for various types of external exposures, consistent with the 2007 recommendations of the ICRP. These coefficients were calculated using the official ICRP/ICRU computational phantoms representing the Reference Adult Male and Reference Adult Female, in conjunction with Monte Carlo codes simulating the transport of radiation within the human body, such as EGSnrc, FLUKA, GEANT4, MCNPX, and PHITS.
The incident radiations and energy ranges considered were external beams of mono-energetic photons of 10 keV-10 GeV, electrons and positrons of 50 keV-10 GeV, neutrons of 0.001 eV-10 GeV, protons of 1 MeV-10 GeV, pions (negative/positive) of 1 MeV-200 GeV, muons (negative/positive) of 1 MeV-10 GeV, and helium ions of 1 MeV/u-100 GeV/u.
From simulations, the absorbed dose to each organ within the reference phantoms was determined. The fluence to effective dose conversion coefficients was derived from the obtained organ dose conversion coefficients, the radiation weighting factor W R , and the tissue weighting factor W T , following the procedure described in ICRP Publication 103.
The operational quantities for photons, neutrons, and electrons continue to provide a good approximation for the conversion coefficients for effective dose for the energy ranges considered in ICRP Publication 74 and ICRU Report 57, but not at the higher energies considered in the present report.
Separate Monte Carlo simulations were made to determine the absorbed dose to the lens of the eye for incident photons, electrons, and neutrons using a stylized model of the eye. Similarly, localized skin-equivalent dose conversion coefficients for electrons and alpha particles are given as derived by Monte Carlo calculations simulating the transport of a normally incident, parallel beam on a tissue-equivalent slab.
Additionally, photon and neutron dose-response functions are given in this report, defined as the absorbed dose per particle fluence. Their use would compensate for the limited spatial resolution of the voxel geometry, as well as for dose enhancement or dose depression at the microscopic level of the marrow cavities.
| Document Under Public Consultation | |  |
Radiological Protection against Radon Exposure
The draft ICRP report "Radiological Protection against Radon Exposure" is under public consultation. ICRP welcomes comments from individuals and groups. The draft document can be downloaded, and comments submitted, through the ICRP website.
In this report, the commission provides updated guidance on radiological protection against radon exposure. The report has been developed considering the recently consolidated ICRP general recommendations, the new scientific knowledge about the radon risk, and the experience gained by many organizations and countries in the control of radon exposure.
The report describes the characteristics of radon exposure, covering sources and transfer mechanisms, the nature of the risk, the exposure conditions, the similarities with other existing exposure situations, and the challenges to manage radon exposure.
The report also provides recommendations on control of radon exposure in workplaces when workers' exposure can reasonably be regarded as being the responsibility of the operating management. In such a case, workers' exposures are considered as occupational and controlled using the corresponding requirements on the basis of the optimization principle and the application, as appropriate, of the dose limit (source: th www.icrp.org)
|
Search Pubmed for