[en] In 2001, the major nuclear organisations in the United Kingdom started development of a document that would identify and facilitate consistent the application of good practice within the industry for clearing and sentencing of articles, substances and wastes which may be clean, or radioactive at very low levels below thresholds of regulatory control. The document includes: (i) Clarification of the industry's interpretation of legislation associated with the clearance and sentencing of articles, substances and wastes which are or have the potential to have been contaminated by radioactivity or activated by nuclear radiations; (ii) Industry agreement on what is considered to be the good practice where legislation is imprecise or unclear, (iii) A standard management framework, adopted by all organisations within the nuclear industry, that should justify safe and efficient clearance of potentially radioactive articles, substances and wastes; and (IV) Agreed guidance on the principles, processes and practices which should be followed for clearances and sentencing The Document mandates a system that allows articles and substances to be released from further control, where this is appropriate, using robust radiological protection principles. The need to avoid sentencing of clean materials as radioactive waste where this is not appropriate, the primacy of bulk, rather than surface radioactivity clearance criteria, and the need to disallow such clearances until all relevant legislation has been satisfied, are all clear principles contained within the document. An interim issue of the Code of Practice was issued in May 2003. This version has been formally adopted by all of the major users of radioactive material in the United Kingdom, and has two main objectives: -Trial use of the concepts at the working level, and - As a basis for further discussion with interested stakeholders. The paper summarises: - How the interim version of the Code of Practice was developed; - The Principles, processes and practices contained within the document, and - How the document will be developed in future. (Author)

[en] The EEC Directive on Qualified Experts in Radiation Protection has been implemented in the United Kingdom by the Ionising Radiations Regulations 1999 (IRR99). These Regulations require Radiation Employers to appoint suitable Radiation Protection Advisers (RPA) who must be consulted in certain circumstances when starting work with, or using ionising radiations. Radiation Protection Advisers have to have a current certificate of competence and, to gain one of these, must have demonstrated their competence in one of two ways either by achieving a National Vocational Qualification in Radiation Protection Practice or by being Certificated by an Assessing Body. Assessing Bodies have to be recognised by the Health and Safety Executive, who undertake a rigorous assessment process to determine whether the proposed Assessing Body is fit to undertake RPA Assessments. By July 2003, only two such Assessing Bodies had been approved in the UK. These two Assessing Bodies are ? RPA 2000 a company established by the four leading Radiation Protection Professional Societies in the UK for assessing anyone in the UK as Radiation Protection Advisers, And ? BNFL established by BNFL to assess the competence of BNFL's own Radiation Protection Advisers. This paper will describe the standards against which Radiation Protection Advisers are assessed, the manner in which each of these two Assessing Bodies carry out the assessment process and their experience to date. The way in which Radiation Employers carry out the appointment process will also be described. Potential future developments of the Assessment Process and standards will also be discussed. (Author)

[en] The monitoring of the LHC (Large Hadron Collider) operation is performed by the OASIS system (Open Analogue Signal Information System). OASIS deals with signals coming from different places to see if the LHC operates as expected. OASIS uses a series of digital converters but to limit the number of digital converters, a switch system is used to select the signal to digitize. Up to 16 analogue signals coming from 104 sensors must be made available for digitizing. Then a 104*16 switching matrix was necessary with a good cross talk behavior and with a few tens of MHz bandwidth. Pickering Interfaces has proposed a large bandwidth matrix based on the LXI platform and including a self-test function

[en] D0 has calculated the luminosity monitor constant for √s= 630 GeV. The inelastic p anti p cross section was interpolated between measurements performed at √s = 546 and 1800 GeV. The geometric acceptance, hardware efficiency, and luminosity-dependent corrections are similar to those previously published for the full Tevatron energy. We find a luminosity-weighted value of σ_L0 = 34.04 ± 1.05 mb, yielding a precision of ± 3.08%

[en] Title 10 Part 20 of the Code of Federal regulations requires that nuclear power plant licensees evaluate worker radiation exposure using a risk-based methodology termed the effective dose equivalent (EDE). EDE is a measure of radiation exposure that represents an individual's risk of stochastic injury from their exposure. EPRI has conducted research into how photons interact with the body. These results have been coupled with information on how the body's organs differ in their susceptibility to radiation injury, to produce a methodology for assessing the effective dose equivalent. The research and the resultant methodology have been described in numerous technical reports, scientific journal articles, and technical meetings. EPRI is working with the Nuclear Energy Institute to have the EPRI effective dose equivalent methodology accepted by the Nuclear Regulatory Commission for use at US nuclear power plants. In order to further familiarize power plant personnel with the methodology, this report summarizes the EDE research and presents some simple guidelines for its implementing the methodology

[en] In a Community that is as integrated, advanced and democratic as ours, the ability to balance a number of different, perhaps almost mutually exclusive, views and requirements is of paramount importance. Health and Safety in general, and radiation protection in particular are a prime example of this in that these is an inherent need to properly balance the benefits received from the use of radioactivity with the risks associated with that use. (orig.)

[en] Composition profiles of the entire film thickness back to the metal-oxide interface were determined using ion bombardment for controlled removal of successive surface layers. Samples of the alloy were exposed to aqueous attack in static and continuous autoclaves at 285⁰C for periods of 1-168 hr. In hydrogen-saturated water of pH 10, a thin (<10 nm) film, rich in chromium oxide forms. This is shown to result from a solid-state growth process. A similar film, rich in chromium oxide, grows on Inconel-600 in pH 10 water containing higher concentrations of dissolved oxygen, but it is rapidly overgrown by a nonpassivating layer of metal hydroxides whose composition and rate of growth vary with the oxygen concentration of the solution. The chemical stability of the alloy surface is likely determined by the magnitude of the solubility of the chromium oxide layer which is formed on initial oxidation

[en] Carbon steel surfaces removed from the boiler inlet and outlet of the coolant system of the nuclear power generating station at Douglas Point, Ontario, have been examined by x-ray diffractometry, scanning electron microscopy, and energy dispersive x-ray spectrometry. In addition to the expected composition product, magnetite, two other phases have been detected: (1) individual particles up to 100μm in diameter on the outermost surface, rich in aluminum and silicon, and having the mica type structure, and (2) a second phase uniformly distributed over the surface at the corrosion film-water interface. The latter phase, present in greater quantity at the boiler inlet, has the same structure (spinel) as does magnetite, and contains in decreasing order of magnitude, Fe, Ni, Al, Si, Mn, and Cr. The composition and structure of the corrosion products are discussed in terms of the composition of the materials in the heat transport system, and current knowledge of corrosion mechanisms and corrosion product stabilities in high temperature aqueous systems

[en] The surface of Monel-400 alloy was exposed to high pH, aqueous corrosion at 285⁰C, under both oxidizing and reducing conditions. After exposures lasting from 0.3 to 335 h, the surfaces were examined by x-ray photoelectron spectroscopy, scanning electron microscopy, and other techniques. Under reducing conditions, no corrosion film forms on the metal surface, but under oxidizing conditions, the first corrosion layer which forms at the solution interface is entirely Ni(OH)₂. This hydroxide, which persists for long times at pH approximately 10 but which rapidly converts to NiO at pH approximately 14, is shown to result from a precipitation process. The composition of the corrosion film is determined by the relative solubilities of nickel and copper at the interface. A composition profile of the corrosion layer beneath the outermost film shows a gradual increase in cuprous ion concentration with increasing depth, probably due to solid-state migration. This suggests that the aqueous corrosion of Monel-400 involves both solid-state oxide growth and an ionic dissolution and precipitation mechanism

[en] The International Labour Office (ILO), based in Geneva, is one of the major UN organisations, and has overall responsibility for occupational safety and health. As part of this overall responsibility, the ILO has adopted a Convention, Code of Practice and supporting documentation on Occupational Radiological Protection. The Convention in particular is a powerful tool to enhance radiological protection, and has been ratified by 47 Member States. The ILO also co-operates closely with the International Atomic Energy Agency (IAEA) in developing supporting documentation and is, for example, one of the co-sponsors of the IAEA Basic Safety Standards. The ILO is a tripartite organisation, representing Employees, Employers and Governments, and has a significant interest in the concepts being proposed by the International Commission on Radiological Protection (ICRP). This presentation represents preliminary views on the latest proposals. (author)