No abstract available

[en] An analysis was made of the radioactivity of enamel samples, containing depleted Uranium and Uranium ore, such as employed by the ceramic industry to produce paving and lining tiles. An investigation was also made of various types of tiles with depleted Uranium containing enamels, in order to evaluate the use hazard for dwelling houses, in particular in regard to the wear of tiled floors by children as a critical group. The risk to the population due to the use of tiles dyed with enamel containing depleted Uranium was considered an undue risk and as such not permissible. (U.K.)

[en] An automatic station for measuring the beta total radioactivity of air has been designed. The station consists in an intake section with a capacity of 384 cubic metres of air a day and a glass fibre ribbon filter and in a detection section with three shielded Geiger counters, a plastic beta detector and a NaI (Tl) crystal detector. This stage is linked to the counting section that processes the data and outputs the values of the radioactivity minimum, mean and maximum. The minimum radioactivity measurable is almost 0.015 pC; for such a radioactivity the relative error is 45%. For the mean values the relative error amounts to almost 10%. This station is therefore particularly reliable for its high sensitivity and for the little relative error

No abstract available

[en] The qualified expert is a well established professional role, presently defined in its duties and responsibilities according to the European Directive 96/29, even if a first definition of his main duties and responsibilities was already given in the Italian law in the first Sixties. According to the most recent law disposal, the qualified expert has a university education level and has received an appropriate training, varying from 120 to 360 work days, in a centre (industries, research centers, hospitals, etc.) with use of ionizing radiations and under the tutor ship of the local qualified expert. The qualification is recognized after passed an exam before special commission of the Ministry of Labour. There are 3 levels of expertise for the qualified expert, related to the level of complexity of the ionizing radiation source

[en] A PF (Plasma Focus) device is being built at the Montecuccolino Laboratory. The machine is now being characterized, however, all radiation protection details had to be worked out before operation could start, with no experimental data available: it proved necessary to extrapolate data from existing PF devices, obtaining (conservative) upper limiting values for radiation emission: 5·10⁸ neutrons (of an energy of 3 keV) per discharge. This value was then used to design all the needed protective measures to reduce dose values to all persons involved to below the Italian legal limit for the general public. As a result, there is no classified personnel, nor any classified areas outside the labyrinth hosting the PF. Thanks to the labyrinth, this was obtained without need for doors, and the control area, albeit safe for personnel, is in direct communication with the PF area. Only concrete shields were used, avoiding entirely the risks of flammable materials such as paraffin or polythene. (author)

[en] A former industrial site was left contaminated by phosphogypsum waste from the production of phosphoric acid. Following prescription by the authorities, a decontamination plan was designed and implemented. Following the plan, a containment pool was built, contaminated grounds were excavated to a depth of 1 m, and the resulting dirt stored in the containment pool, that was then covered with reinforced concrete. Uncontaminated, compatible dirt was brought in to replace the dirt removed. Measurements and evaluations proved that design objectives were met or exceeded and the site fully reclaimed. (author)

[en] Measurements on dirt samples from dismissed quarries located in the Venice lagoon area and immediate surroundings yield evidence that the quarries have been used (probably near the end of the fifties) as dumps for phosphogypsum waste from the production of phosphoric acid and fertilisers. In the production of phosphoric acid, approx. 90% of the ²²⁶Ra present precipitates into a solid phase as insoluble radium sulphate, a slurry called phosphogypsum. ²²⁶Ra and its daughters, particularly ²¹⁰Pb, ²¹⁰Po and gaseous ²²²Rn, are extremely dangerous. Mean and peak concentrations of ²²⁶Ra of its daughters ²¹⁴Bi and ²¹⁴Pb were measured. To evaluate the solubility of the radionuclide, a chemical elution of the samples was obtained by addition of distilled water and acetic acid and gamma- and alfa- spectrometry measurements of the resulting liquid samples were performed. On the basis of the results obtained, the authors have performed an 'evaluation of radiological impact' for the area population, that showed that phosphogypsum waste is best left in site. (author)

[en] For an optimal tuning of the radiation protection planning, a Monte Carlo model using the MCNPX code has been built, allowing an accurate estimate of the spectrometric and geometrical characteristics of photoneutrons generated by a Varian TrueBeam Stx© medical linear accelerator. We considered in our study a device working at the reference energy for clinical applications of 15 MV, stemmed from a Varian Clinac©2100 modeled starting from data collected thanks to several papers available in the literature. The model results were compared with neutron and photon dose measurements inside and outside the bunker hosting the accelerator obtaining a complete dose map. Normalized neutron fluences were tallied in different positions at the patient plane and at different depths. A sensitivity analysis with respect to the flattening filter material were performed to enlighten aspects that could influence the photoneutron production. - Highlights: • A Monte Carlo model of a medical LINAC and of the hosting bunker is presented. • The photoneutrons production is analysed. • The related radiation protection issues have been considered.

[en] In a Plasma Focus device the plasma collapses into the pinch where it reaches thermonuclear conditions for a few tens of nanoseconds, becoming a multi-radiation source. The nature of the radiation generated depends on the gas filling the chamber and the device working parameters. The self-collimated electron beam generated in the backward direction with respect to the plasma motion is one of the main radiation sources of interest also for medical applications. The electron beam may be guided against a high Z material target to produce an X-ray beam. This technique offers an ultra-high dose rate source of X-rays, able to deliver during the pinch a massive dose (up to 1 Gy per discharge for the PFMA-3 test device), as measured with EBT3 Gafchromicâ’¸film tissue equivalent dosimeters. Given the stochastic behavior of the discharge process, a reliable on-line estimate of the dose-delivered is a very challenging task, in some way preventing a systematic application as a potentially interesting therapy device. This work presents an approach to linking the dose registered by the EBT3 Gafchromicâ’¸films with the information contained in the signal recorded during the current discharge process. Processing the signal with the Wigner-Ville distribution, a spectrogram was obtained, displaying the information on intensity at various frequency scales, identifying the band of frequencies representative of the pinch events and define some patterns correlated with the dose.