Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RADIATION PROTECTION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
PubMed2004

Radiation protection aspects of the cosmic radiation exposure of aircraft crew.

Aircraft crew and frequent flyers are exposed to elevated levels of cosmic radiation of galactic and solar origin and secondary radiation produced in the atmosphere, the aircraft structure and its contents. Following recommendations of the International Commission on Radiological Protection in Publication 60, the European Union introduced a revised Basic Safety Standards Directive, which included exposure to natural sources of ionising radiation, including cosmic radiation, as occupational exposure. The revised Directive has been incorporated into laws and regulations in the European Union Member States. Where the assessment of the occupational exposure of aircraft crew is necessary, the preferred approach to monitoring is by the recording of staff flying times and calculated route doses. Route doses are to be validated by measurements. This paper gives the general background, and considers the radiation protection aspects of the cosmic radiation exposure of aircraft crew, with the focus on the situation in Europe.

Aircraft↗
PubMed2002

Radiation protection during percutaneous nephrolithotomy: a new urologic surgery radiation shield.

BACKGROUND AND PURPOSE: As endourology becomes an important part of the practice of urology, the use of fluoroscopic guidance has increased the exposure of urologists to the possibly deleterious effects of radiation. There is a need for a method of radiation protection for percutaneous nephrolithotomy (PCNL), as the exposure from radiation scatter may be significant, depending on the difficulty of establishing access. PATIENTS AND METHODS: We ascertained the effectiveness of a newly modified radiation shield during PCNL. Exposure readings were taken using a thermoluminescent dose monitor placed different distances from the radiation source during six PCNLs. We compared the exposure readings with and without the shield. RESULTS: The shield was able to reduce the radiation by an average of 96.1% at a distance of 25 cm and 71.2% at a distance of 50 cm from the source. CONCLUSION: The shield can be used as one step toward the goal of reducing surgeon radiation exposure. Other methods, such as dose-minimizing imaging protocols and adaptation of equipment optimized to reduce exposure, are also important measures in creating a safe environment for both the urologist and the patient.

Adult↗
PubMed1988

Radiation protection guidelines for space missions.

The current radiation protection guidelines of the National Aeronautics and Space Administration (NASA) were recommended in 1970. The career limit was set at 4.0 Sv (400 rem). Using the same approach as in 1970 but current risk estimates, a considerably lower career limit would obtain today. Also, there is now much more information about the radiation environments that will be experienced in different missions. Furthermore, since 1970 women have joined the ranks of the astronauts. For these and other reasons, it was considered necessary to re-examine the radiation protection guidelines. This task has been undertaken by the National Council on Radiation Protection and Measurements Scientific Committee 75. Within the magnetosphere, the radiation environment varies with altitude and inclination of the orbit. In outer space missions, galactic cosmic rays, with the small but important heavy-ion component, determine the radiation environment. The new recommendations for career dose limits, based on lifetime excess risk of cancer mortality, take into account age at first exposure and sex. The career limits range from 1.0 Sv (100 rem) for a 24-y-old female up to 4.0 Sv (400 rem) for a 55-y-old male, compared with the previous single limit of 4.0 Sv (400 rem). The career limit for the lens of the eye has been reduced from 6.0 Sv (600 rem) to 4.0 Sv (400 rem).

Female↗
PubMed1990

[Basic and advanced training in radiation protection in stomatology].

Considering the importance of radiation protection in dental radiology and the respective legal regulations of the GDR, objectives and contents of basic and advanced training of responsible co-workers in radiation protection are described. Particular organisational aspects regarding training courses in the National Board for Atomic Safety and Radiation Protection are outlined.

Humans↗
PubMed1996

[Basis of radiation protection].

After an introduction, three selected contributions to the 10th Course on Radiation Protection held at the University Hospital of Basel are presented. The principles of radiation protection and new Swiss legislation are discussed as the basis for radiological protection. Ways are proposed of reducing radiation exposure while optimizing the X-ray picture with a minimum dose to patient and personnel. Radiation effects from low doses. From the beginning, life on this planet has been exposed to ionizing radiation from natural sources. For about one century additional irradiation has reached us from man-made sources as well. In Switzerland the overall annual radiation exposure from ambient and man-made sources amounts to about 4 mSv. The terrestrial and cosmic radiation and natural radionuclids in the body cause about 1.17 mSv (29%). As much as 1.6 mSv (40%) results from exposure to radon and its progenies, primarily inside homes. Medical applications contribute approximately 1 mSv (26%) to the annual radiation exposure and releases from atomic weapons, nuclear facilities and miscellaneous industrial operations yield less than 0.12 mSv (< 5%) to the annual dose. Observations of detrimental radiation effects from intermediate to high doses are challenged by observations of biopositive adaptive responses and hormesis following low dose exposure. The important question, whether cellular adaptive response or hormesis could cause beneficial effects to the human organism that would outweigh the detrimental effects attributed to low radiation doses, remains to be resolved. Whether radiation exerts a detrimental, inhibitory, modifying or even beneficial effect is likely to result from identical molecular lesions but to depend upon their quantity, localization and time scale of initiation, as well as the specific responsiveness of the cellular systems involved. For matters of radiation protection the bionegative radiation effects are classified as deterministic effects or stochastic effects respectively. The various histopathological reactions of tissues and organs following localized tissue irradiation, and the radiation syndromes following total body irradiation, constitute the deterministic effects. There will be a threshold below which deterministic effects do not appear and spontaneous incidences are not known. For low dose risk considerations deterministic effects are of no significance. Genetic effects and carcinogenesis are said to be stochastic effects. Characteristically the probability of stochastic effects increases with dose but the severity of the effects is independent of the dose. The shape of the dose-response relationship at intermediate to high dose levels is linear-quadratic. For exposure to low doses the response becomes linear, as is to be expected for a linear-quadratic function at low dose. No threshold is assumed for stochastic effects. The estimate of probability of fatal cancer by the ICRP is 4 x 10(-2) per Sv for the working population and 5 x 10(-2) per Sv for the total population. Their estimate of probability of serious hereditary disorders within the first two generations is 1 x 10(-2) per Sv. The highest probability coefficient is attributed to mental retardation following exposure in utero. Within the sensitive period at 8-15 weeks of gestation, a risk probability of 40 x 10(-2) per Sv is assumed but a threshold at 0.1 Sv is not excluded. Conclusions drawn from experiments, clinical observations and epidemiological studies following intermediate to high radiation exposures attribute a mutagenic and carcinogenic competence to all radiation doses. Microdosimetric considerations support this assumption. This conclusion cannot be confirmed experimentally nor by epidemiological studies of populations living under different conditions from natural sources of radiation. Nevertheless, a change in the present restrictive radiation protection policy does not yet appear appropriate.

Diagnostic Imaging↗
PubMed2004

Radiation protection principles of NCRP.

The current recommendations of the National Council on Radiation Protection and Measurements (NCRP) relative to ionizing radiation are based on radiation protection principles that developed historically as information about radiation effects on human populations became available. Because the NCRP Charter states that the NCRP will cooperate with the International Commission on Radiological Protection (ICRP), the basic principles and recommendations for radiation protection of the NCRP are closely coupled with those of the ICRP. Thus, the fundamental principles of justification, optimization, and dose limitation as initially stated in ICRP Publication 26 have been adopted and applied by the NCRP in its recommendations. ICRP and NCRP recommendations on dose limitation for the general public and for occupationally exposed individuals are based on the same analyses of radiation risk, and, while similar, there are differences reflecting the aspects of radiation application and exposure circumstances unique to the United States. The NCRP has recently extended its guidance to address exposure to individuals engaged in space activities. Several reports have been issued or are in preparation to provide recommendations on dose limitation and the development of radiation safety programs to apply the radiation protection principles in space activities. The biological basis for these recommendations is provided in these and accompanying NCRP reports. Recommendations for the application of basic radiation protection principles have been made in many reports over the years. Those that are most current appear in approximately 50 reports published in the last 15 y. These address radiation safety practices in industrial and medical institutions, control of radionuclides in the environment, protection of the public, and assessment of radiation risk. Some of the aspects of these recommendations will be discussed. Current recommendations related to radiation safety practice are based on the principles and dose limits specified in Report No. 116. The limits are based on estimates of the risk of fatal cancer and an assessment of the risk that should be tolerated by workers who are occupationally exposed and by the general public. These levels of risk are related to other risks that individuals accept in their lives. Looking to the future, one might consider other directions that the NCRP could take in developing radiation safety recommendations that are still based upon the stated principles, such as relating dose to loss of life expectancy instead of fatal cancer risk. It may also be that the principles of justification, optimization, and dose limitation should be reconsidered. For example, the NCRP may make recommendations about the relationship of radiation dose to various biological effects or outcomes and the resulting estimates of risk, but not specify dose limits. This would relieve the NCRP of the necessity to speculate about acceptable risks. One can also imagine that the principle of justification could be applied not only to the introduction of a new source of radiation, but also to the removal of an existing source of radiation, i.e., the idea of justifying decontamination efforts. It is clear that as we move into the 21st century there will be a continuing need for the NCRP to identify the principles upon which radiation protection is to be based and to provide guidance on the application of those principles for the many beneficial uses of radiation and radioactive materials in society.

Environmental Exposure↗
PubMed2006

An analysis of public-interest group positions on radiation protection.

The history of radiation risk management is replete with contentious public debate between public interest groups and the technical community of radiation protection professionals. To promote a deeper understanding of this phenomenon, this paper describes the rationales and values underlying public-interest group positions in one radiation risk domain (low-level waste) and contrasts them with those of the technical community. Public interest group objections to recycling of radioactivity-contaminated materials and to discarding of other low-level wastes are made on fairness, risk assessment, and energy-policy grounds. Concerns about procedural fairness stem from the continuing use of top-down expert-driven, rather than deliberative, systems for low-level waste policy-making. Concerns about distributional fairness arise because the benefits and risks of alterative low-level waste policies accrue to different stakeholders. Risk assessment is faulted for failure to acknowledge hidden subjective assumptions (e.g., on screening vigilance in materials recycling, on integrity of disposal facilities in the far future). Skepticism of technological risk management arises from a history peppered with unexpected untoward events that lay outside the design bases of protection systems. Finally, public interest groups view low-level waste issues as part of a larger debate on wise and legitimate energy policy, and are reluctant to support measures that provide relief to a nuclear industry that, in their view, established itself outside the democratic process.

Consumer Advocacy↗
PubMed1991

A proposed biophysical framework for radiation protection calculations using summation of iso-risk contributions of different radiations.

A biophysical framework for administrative radiation protection calculation using summation of iso-risk contribution of different radiation components is presented. It addresses some of the concerns with the present system but would preserve the present linear mathematical framework and hence the massive literature of numerical calculations in radiation protection.

Biophysical Phenomena↗
PubMed1980

Risk assessment for radiation protection purposes.

In defining criteria for good protection against ionizing radiation, it is important to assess quantitatively the likely risk of any radiation exposure. The 'somatic' risks to the individual result mainly from induction of cancer in the organs irradiated, and these risks can now be estimated on the basis of numerous detailed epidemiological surveys of exposed human populations. Estimates of the risk of hereditary effects, from genetic changes induced in germ cells, are based largely on the frequency with which such effects are induced in other species. In both cases the risk at very low dose can be inferred using knowledge of the way in which radiation damage is caused in tissues. Coherent systems of radiation protection are based on a restriction of doses to the whole body and to individual organs, such that the induction of cancer and genetic harm is infrequent, and the threshold dose for causing other, 'non-stochastic', effects is not exceeded.

Dose-Response Relationship, Radiation↗
PubMed1988

Future development of biological understanding of radiation protection: implications of nonstochastic effects.

Radiation-protection standards are based on minimizing or preventing biological effects in exposed populations. Radiation-induced biological effects can be classified as stochastic--malignant and hereditary diseases for which the probability of an effect occurring is a function of dose without threshold--and nonstochastic--inflammatory and degenerative diseases for which the severity and frequency of the effect varies with the dose and for which a threshold is present. The current International Commission on Radiation Protection (ICRP) approach for setting limits for intakes of radionuclides by workers, which accounts for doses to significantly exposed organs of the body, is based on limitation of stochastic effects in most situations. When setting exposure limits, nonstochastic effects are generally considered to be unlikely at the limits for stochastic effects. In some situations, limits based on prevention of nonstochastic effects are lower than for stochastic effects. This review considers the threshold radiation doses for thyroid, bone, liver and lung and their relationship to the limits recommended by the ICRP and the cancer risks at the limits. This review indicates that the threshold dose for nonstochastic effects in thyroid and lung is much above the dose limit as advocated by ICRP. The threshold dose for nonstochastic effects in bone and liver is much closer to the dose limit, but protection from nonstochastic effects should still be afforded by the dose limits.

Animals↗
PubMed1981

Effect of glutaurine and its derivatives and their combinations with radiation protective substances upon irradiated mice.

The radiation protective effects of glutaurine (gamma-L-glutamyl-taurine, Litoralon), and of some of its derivatives, as well as of their combinations with substances of the amino-alkyl-thiol group, have been investigated in mice. The results suggest that glutaurine possesses a radiation protective effect in animals irradiated with LD50/30 of roentgen rays and 60Co gamma rays. The compound has a favourable effect also when administered after irradiation. Its protective effect is especially marked in case of prolonged irradiation. Among the combinations best results were obtained by its simultaneous administration with subminimal doses of AET or cystamine. Some of its derivatives also exhibited considerable protection against irradiation with roentgen rays.

Animals↗
PubMed2001

Training and accreditation in radiation protection for interventional radiology.

Training in radiation protection is a basic aspect of the optimisation of medical exposures. Council Directive 97/43/EURATOM establishes the need for an adequate theoretical and practical training of the staff working in radiological practices, and competence in radiation, for which Member States shall ensure the establishment of appropriate curricula. Keeping in mind the different specialities and professional responsibilities, training curricula must be proposed and endorsed to achieve a common core of knowledge in radiation protection throughout Europe, for different groups of health workers. In interventional radiology, previous initiatives led to the definition of a syllabus of educational objectives and to its testing in a specific course. The present paper presents educational objectives for interventional radiology, developed in the framework of the DIMOND European concerted action.

Accreditation↗
PubMed2002

Fluence-based and microdosimetric event-based methods for radiation protection in space.

The National Council on Radiation Protection and Measurements (NCRP) has recently published a report (Report #137) that discusses various aspects of the concepts used in radiation protection and the difficulties in measuring the radiation environment in spacecraft for the estimation of radiation risk to space travelers. Two novel dosimetric methodologies, fluence-based and microdosimetric event-based methods, are discussed and evaluated, along with the more conventional quality factor/LET method. It was concluded that for the present, any reason to switch to a new methodology is not compelling. It is suggested that because of certain drawbacks in the presently-used conventional method, these alternative methodologies should be kept in mind. As new data become available and dosimetric techniques become more refined, the question should be revisited and that in the future, significant improvement might be realized. In addition, such concepts as equivalent dose and organ dose equivalent are discussed and various problems regarding the measurement/estimation of these quantities are presented.

Cosmic Radiation↗
PubMed2002

Radiation protection system for interventional procedures of the upper extremity: evaluation in a phantom model.

PURPOSE: To design a radiation protection system for interventional procedures of the upper extremity and to evaluate the effectiveness of the system. MATERIALS AND METHODS: The radiation protection system consisted of an image intensifier (I-I) hood and x-ray tube cover. The I-I hood encircled the I-I to protect against scattered radiation from the patient's upper extremity and the table. The I-I hood consisted of four components: a device for attaching the hoods, two acrylate hoods with an 0.50-mm Pb equivalent, and a lead curtain hood with a 0.35-mm Pb equivalent. The x-ray tube cover was constructed of lead curtain to protect against backscattering radiation from the catheter table. An extremity phantom was used to measure the scattered radiation around the angiographic apparatus. The scattering dose rates were measured with an ionization dosimeter with and without a radiation protection system. The heights of the measuring points from the floor were 50 cm (operator's lower limbs), 100 cm (operator's abdomen), and 150 cm (operator's head/neck). RESULTS: The dose rates were reduced most with the combination of the I-I hood and the x-ray tube cover. The x-ray tube cover was effective in reducing scattering when it was set close to the table and the phantom. The maximum percentage decreases in dose rates by the radiation protection system were 99% at 50 cm, 73% at 100 cm, and 100% at 150 cm. Therefore, at 50 cm and 150 cm, the high-dose-rate area around the angiographic apparatus was reduced almost completely by the radiation protection system. CONCLUSION: The radiation protection system for interventional procedures of the upper extremity was effective in reducing scattered radiation around the angiographic apparatus.

Angiography↗