Abstract: A radiation dosimetry apparatus and method use a scintillating optical fiber array for detecting dose levels. The scintillating optical fiber detectors generate optical energy in response to a predetermined type of radiation, and are coupled to collection optical fibers that transmit the optical energy to a photo-detector for conversion to an electrical signal. The detectors may be embedded in one or more modular, water-equivalent phantom slabs. A repeatable connector couples the collection fibers to the photo-detector, maintaining the fiber ends in a predetermined spatial relationship. The detector fibers may be distributed as desired in a three-dimensional detection space, and may be oriented with their longitudinal axes at different orientations relative to a transmission axis of an incident radiation beam. A calibration method uses two measurements in two spectral windows, one with irradiation of the scintillator at a known dose and one with only irradiation of the collection fiber.

Abstract: A survey method and system for survey method and system for detecting and/or characterizing a radiation field The method may include acquiring energy-dependent radiation spectral data at a location of interest in a radiation field using a detector, wherein the energy-dependent radiation spectral data may include counts versus energy. The method may further include acquiring radiation spectral data at at least one other location wherein the at least one other location is positioned relative to the location of interest.

Abstract: A radiation dosimetry quality assurance system is disclosed that includes a three-dimensional (3D) phantom extending along a longitudinal axis to form an exterior surface and an interior volume and a passage formed to extend into the interior volume of the 3D phantom to removeably receive a detector array therein. The system also includes an angular-compensation system coupled to the exterior surface of the 3D phantom and having a physical contour extending from the exterior surface of the 3D phantom and configured to control an angular dependence of the detector array during measurement of the actual radiation dose delivered by the radiation delivery system. The system further includes a detector-angle adjustment system configured to allow selection of a relative position of the detector array with respect to a radiation source of the radiation delivery system during measurement of the actual radiation dose delivered during the planned medical process.

Abstract: A method and an apparatus for measuring the dose, the dose rate and/or the composition of radiation is disclosed. In the method, a detector means is exposed to a radiation environment, the detector means comprising an array of radiation sensing detector elements. The detector means is switched in a sensitive state for the duration of a sensitive time period, and during said sensitive time period, an interaction pattern generated by individual radiation quanta interacting with one or more of the detector elements is recorded. The duration of the sensitive time period can be precisely adapted to the intensity of the radiation that has to be recorded. The interaction pattern is analyzed to distinguish individual radiation quanta received during the sensitive time period, and a radiation category is assigned to each of the distinguished radiation quanta based on its corresponding interaction pattern.

Abstract: The invention consists of equipment and a process, based on ionizing radiation dosimeters, whereby one or several of these dosimeters are placed in the patient. The identity of these dosimeters, and the information collected by them are entered in a computer system, which applies an algorithm to determine the surface dose and estimate the dose in organs. The preferred embodiment is described, in which the dosimeter is based on the thermoluminescence principle, and also includes a dosimeter identifier, a dosimeter reader, the software, and the process for handling the dosimeters and the information.

Abstract: Methods, systems, devices, and computer program products include positioning disposable single-use radiation sensor patches that have adhesive means onto the skin of a patient to evaluate the radiation dose delivered during a treatment session. The sensor patches are configured to be minimally obtrusive and operate without the use of externally extending power chords or lead wires.

Abstract: A method and an apparatus for measuring the dose, the dose rate and/or the composition of radiation is disclosed. In the method, a detector means is exposed to a radiation environment, the detector means comprising an array of radiation sensing detector elements. The detector means is switched in a sensitive state for the duration of a sensitive time period, and during said sensitive time period, an interaction pattern generated by individual radiation quanta interacting with one or more of the detector elements is recorded. The duration of the sensitive time period can be precisely adapted to the intensity of the radiation that has to be recorded. The interaction pattern is analyzed to distinguish individual radiation quanta received during the sensitive time period, and a radiation category is assigned to each of the distinguished radiation quanta based on its corresponding interaction pattern.

Abstract: Disclosed is a thyroid uptake measurement apparatus, in which a radiation attenuation filter is detachably provided at the leading end of a collimator of a radiation detector. The radiation attenuation filter inhibits the saturation of signals when gamma rays exceeding the maximum counting rate are entered. Accordingly, it is possible to inhibit the distortion of signals when the pile-up of the signals increases by an increase in the radiation decay. Moreover, the use of the radiation attenuation filter can significantly improve the scatter fraction, that is, the ratio of scattered radiation/total radiation generated by material scatter of radiation.

Abstract: A method and an apparatus for measuring the dose, the dose rate and/or the composition of radiation is disclosed. In the method, a detector means is exposed to a radiation environment, the detector means comprising an array of radiation sensing detector elements. The detector means is switched in a sensitive state for the duration of a sensitive time period, and during said sensitive time period, an interaction pattern generated by individual radiation quanta interacting with one or more of the detector elements is recorded. The duration of the sensitive time period can be precisely adapted to the intensity of the radiation that has to be recorded. The interaction pattern is analyzed to distinguish individual radiation quanta received during the sensitive time period, and a radiation category is assigned to each of the distinguished radiation quanta based on its corresponding interaction pattern.

Abstract: A detector response correction arrangement and method is proposed for online determination of correction factors for arbitrary positions from arbitrary incident fluence distributions. As modern radiotherapy utilizes more of the available degrees of freedom of radiation machines, dosimetry has to be able to present reliable measurements for all these degrees of freedom. To determine correction factors online during measurement, Monte Carlo technique is used to precalculate fluence pencil kernels from a monodirectional beam to fully describe the particle fluence in an irradiated medium. Assuming that the particle fluence is not significantly altered by the introduction of a small detector volume, the fluence pencil kernels (212) can be integrated (214), and correction factors (216) determined, e.g. by Cavity Theory, in different positions for the detector material.

Abstract: An implantable medical apparatus comprises a solid state electronic circuit, an ionizing radiation exposure sensor, an ionizing radiation dose rate sensor, and a controller circuit. The ionizing radiation exposure sensor is configured to detect an exposure of the solid state electronic circuit to ionizing radiation, and generate an indication of a non-single-event-upset (non-SEU) effect to the solid state electronic circuit from the exposure to ionizing radiation, wherein the sensor comprises an accumulated ionizing radiation exposure sensor. The controller circuit is configured to blank the indication from the accumulated ionizing radiation exposure sensor when the radiation dose rate sensor indicates that flux ionizing radiation exceeds a flux ionizing radiation threshold.

Abstract: This invention provides a radiation dosimeter and new method of operation which comprise two types of the metal-oxide-semiconductor field-effect transistor (MOSFET) circuits allowing to amplify the threshold voltage changes due to radiation and provide temperature compensation. The first type dosimeter is a radiation integrated circuit (RADIC) which includes two radiation field-effect transistors (RADFET) and two MOSFETs, integrated into the same substrate. The second type of radiation circuit includes two RADFETs, integrated into the same substrate, and two resistors. The amplification of the threshold voltage change is achieved by using amplification principles of an MOSFET inverter. In both cases, under the ionizing irradiation, the gate of first RADFET is forward biased and the gate of second RADFET is biased off. In the reading mode the amplified differential threshold voltage change is measured. The increased radiation sensitivity allows to measure of the milli-rad doses.

Abstract: A dosimeter comprising an ionizing radiation detector array is used to generally encompass a three dimensional geometric shape such as that employed as a phantom in radiation dosimetry measurements. The ionizing radiation detector array may include passive or active detectors. The active detectors in the array may comprise diodes, ionization chambers, luminescent sensors or amorphous silicon. The three dimensional geometric shape may comprise a shape defined by a closed directrix, wherein each of a plurality of detectors within the ionizing detector array is within an envelope defined by a generatrix of the directrix. The closed directrix may be an open or closed cylinder, or a structure having a cross section described by a polygon. The plurality of detectors may only be positioned on or at least proximate the envelope.

Abstract: Methods, systems, devices, and computer program products include positioning single-use radiation sensor patches that have adhesive onto the skin of a patient to evaluate the radiation dose delivered during a medical procedure or treatment session. The sensor patches are configured to be relatively unobtrusive and operate during radiation without the use of externally extending power cords or lead wires.

Abstract: The present invention relates to a device and method for determining one or more characteristics of radiation using a sensor comprising one or more detector units capable of counting the number of photon or charged particle of said radiation impinging on said sensor in or above a determined energy range.

Abstract: An X-ray detector includes an X-ray photoelectric conversion layer configured to produce electric charges in proportion to X-ray irradiation incident on the layer, a collecting electrode configured to collect the electric charges produced by the X-ray photoelectric conversion layer, a common electrode disposed on a surface of the X-ray photoelectric conversion layer opposite to the collecting electrode, a storage capacitor configured to store the electric charges collected by the collecting electrode, and a readout unit configured to read out the electric charges stored in the storage capacitor. A voltage is to be applied between the collecting electrode and the common electrode. The X-ray photoelectric conversion layer is formed of a polycrystalline oxide.

Abstract: A radiological imaging apparatus using a semiconductor radiation detector to make it possible to reduce a radiation measurement off time that may result from an attempt to avoid polarization, the radiological imaging apparatus comprising a capacitor that applies a voltage to a semiconductor radiation detector that detects a radiation from a subject, first current regulated means for conducting a charge current to the capacitor, and second current regulated means for conducting a discharge current from the capacitor, or comprising a capacitor that applies a voltage to the semiconductor radiation detector, a first resistor that conducts a charge current to and a discharge current from the capacitor, and a second resistor connected in parallel with the first resistor to subject the capacitor to charging and discharging.

Abstract: Methods, systems, devices, and computer program products include positioning single-use radiation sensor patches that have adhesive means onto the skin of a patient to evaluate the radiation dose delivered during a treatment session. The sensor patches are configured to be minimally obtrusive and operate without the use of externally extending power cords or lead wires.

Abstract: A method of spectrometric photon dosimetry for integrally and nuclide-specifically determining a gamma dose rate for X-ray and gamma radiation. The method includes measuring a spectrum in at least one energy group or at least one interval group. The pulse height distribution is with a spectrometer and a pulse height analyzer. The number of channels of the spectrometer is such that a map of the pulse height distribution at a requisite resolution over an energy can be made. The measured pulse height distribution is converted into a photon spectrum using a deconvolution procedure that uses response functions having the same energy resolution as the pulse height distribution. The dose spectrum is calculated using dose conversion factors that are energy-dependent and related to the mean energy of a respective corresponding energy interval. The integral dose or dose rate is determined by summing the dose spectrum.

Abstract: A system for determining an amount of radiation includes a dosimeter configured to receive the amount of radiation, the dosimeter comprising a circuit having a resonant frequency, such that the resonant frequency of the circuit changes according to the amount of radiation received by the dosimeter, the dosimeter further configured to absorb RF energy at the resonant frequency of the circuit; a radio frequency (RF) transmitter configured to transmit the RF energy at the resonant frequency to the dosimeter; and a receiver configured to determine the resonant frequency of the dosimeter based on the absorbed RF energy, wherein the amount of radiation is determined based on the resonant frequency.

Abstract: A radiation beam analyzer for measuring the distribution and intensity of radiation produced by a Cyberknife®. The analyzer employs a relative small tank of water into which a sensor is placed. The distance between the sensor and the radiation source is not varied. There are two methods to maintain the SAD (source to axis distance) constant. A first method maintains the position of detector fixed, utilizing a holder designed to retain the detector, and raises or lowers the small tank of water. A second method moves the detector up or down with a raising and lower mechanism in one direction and synchronically moves the small tank of water in the opposite direction with another raising and lowering mechanism. The second method also keeps the SAD constant. These methods position the detector relative to the radiation source to simulate the location of a malady within a patient's body.

Abstract: An assembly (13) for monitoring ionising radiation comprises a detector substrate (2) for generating electronic charge responsive to incident ionising radiation, the detector substrate (2) having an array of ionising radiation sense volumes (12) formed in it. A circuit substrate (14) supporting an array of read-out circuits (16) corresponding to the array of sense volumes is mechanically and electrically coupled to the detector substrate (14). Each of the read-out circuits (16) is switchable between first and second charge integration modes for receiving charge from a corresponding sense volume. A charge integration circuit (30) is configured in the first charge integration mode to integrate charge corresponding to sensing of a single ionising radiation detection event in a corresponding sense volume and in the second charge integrating mode to integrate charge corresponding to sensing a plurality of ionising radiation detection events in the corresponding sense volume.

Abstract: Methods, systems, devices, and computer program products include positioning single-use radiation internal dosimeters with MOSFETs into a patient to evaluate the radiation dose delivered during a medical procedure or treatment session. The MOSFETs can be unpowered during irradiation.

Abstract: The present invention relates to a radiation image capturing system. A radiation detector of a radiation detecting cassette detects a radiation that has passed through a patient, and an accumulated exposed radiation dose calculator calculates an accumulated exposed radiation dose by accumulating radiation image information detected by the radiation detector, at every image capturing. The calculated accumulated exposed radiation dose is transmitted, together with cassette ID information, to a console. In the console, a status determining unit compares the accumulated exposed radiation dose with an allowable accumulated exposed radiation dose for the radiation detecting cassette to determine the status of the radiation detecting cassette, and issues a warning based on the determined status.

Abstract: This document discusses, among other things, an implantable apparatus comprising a plurality of solid state electronic circuits disposed at a plurality of different locations in the apparatus, a plurality of ionizing radiation exposure sensors disposed at the different locations and configured to generate an indication of a non-single-event-upset (non-SEU) effect to the solid state electronic circuit from an exposure to ionizing radiation, wherein the ionizing radiation exposure sensors respectively monitor at least two different types of operating parameters of respectively correspondingly located solid state circuits, and a controller circuit communicatively coupled to the ionizing radiation exposure sensors, wherein the controller circuit is configured to quantify the effect to the solid state electronic circuits using the different monitored operating parameters.

Abstract: A dosimeter is disclosed for use in container including outer walls defining an interior volume, the dosimeter including: a radon detection element adapted to detect a radon level for the interior volume; a neutron detection element adapted detect a neutron level for the interior volume. The dosimeter is adapted to measure the radon level and neutron level for a period of time, compare the measured radon level to a first threshold, compare the measured neutron level to a second threshold, and determine information indicative of the presence or absence of fissile material within the interior volume based on the comparisons.

Abstract: A radiation image detection method including the steps of: detecting from a radiation image detector including multitudes of pixels disposed two-dimensionally, each having a TFT switch, an analog image signal of each pixel flowing out through each data line by sequentially switching ON the TFT switches connected to each scanning line on a scanning line-by-scanning line basis; detecting an analog leak level flowing out through each data line with the TFT switches connected to each of the scanning lines being switched OFF each time before switching ON the TFT switches on a scanning line-by-scanning line basis when converting the detected analog image signal to a digital image signal and outputting; and correcting the analog image signal before being converted to the digital image signal based on the leak level.

Abstract: Methods, systems, devices, and computer program products include positioning single-use radiation sensor patches that have adhesive means onto the skin of a patient to evaluate the radiation dose delivered during a treatment session. The sensor patches are configured to be minimally obtrusive and operate without the use of externally extending power cords or lead wires.

Abstract: A personal radiation monitor worn by a person who may be exposed to potentially harmful radiation includes a main unit and a radiation sensor cartridge which is matable with and removable from the main unit of the monitor. The removable sensor cartridge includes one or more radiation sensor elements for detecting radiation, and further includes an electronic memory having stored therein calibration and identification information relating to the type of radiation and/or frequency bands of radiation which the sensor or sensors are designed to detect. The sensor cartridge is easily removable from the main unit of the monitor so that one sensor cartridge is interchangeable by the end user with another sensor cartridge.

Abstract: A method for real-time measurement of a local dose received by a region of a target upon bombardment of the target by an incident beam of hadrons generates at least prompt gamma rays and neutrons. The particles emitted by the target are measured by collimating the region of the target and by placing a detector at a distance L from the region of the target to be measured. The detector is linked to a device for particle energy and time-of-flight measurement, in which the number of prompt gamma rays received by the detector is determined by selecting the recorded events, and a two-directional charged-particle detection system, placed in the beam of incident hadrons before the target, is used so as to obtain the transverse position of the incident hadrons in order to provide spatial information about the prompt gamma rays.

Abstract: A method for determining parameters of a beam is disclosed. As a part of a disclosed method, a beam is received at an image detection array where charges are generated and collected, at a plurality of pixels. Values associated with at least one of a plurality of parameters of the beam are determined by integrating information supplied from each of the pixels. Feedback is generated that represents the values.

Abstract: Radiation detector (1) for measuring one or more characteristics of a radiation, comprising one or more detector pixels (3), a clock pulse generator, each detector pixel (3) comprising a sensor (20) producing an electrical signal in response to an event of a photon or charged particle of said radiation impinging on said sensor (20); a pixel electronics (24) adapted for receiving and processing said electrical signal, comprising an analog processing unit (62) for amplifying and shaping said electrical signal and producing a shaped pulse said pixel electronics (24) comprises time determination unit (51) for counting the TOT-count, the TOT-count being the number of clock pulses occurring during the time interval when said shaped pulse is above a threshold. Said pixel electronics comprises a plurality of event counters (82), each event counter (82) counting the number of events having a TOT-count in a predefined ranges.

Abstract: A dosimeter and an associated method for detecting radiation are provided. A dosimeter includes a complementary pair of transistors, such as a first transistor that is doped in accordance with a first conductivity type, such as an n-doped metal oxide semiconductor field effect transistor (MOSFET) and a second transistor that is doped in accordance with a second conductivity type, different than the first conductivity type, such as a p-doped MOSFET. The first and second transistors may be configured to generate respective outputs that shift in opposite directions in response to radiation. The dosimeter may also include a circuit element configured to determine a measure of the radiation based upon a difference between the respective outputs of the first and second transistors. The circuit element may include an amplifier configured to amplify the difference between the respective outputs of the first and second transistors.

Abstract: A direct ion storage (DIS) radiation detector or dosimeter has a design that is easy and low cost to manufacture using semiconductor processing techniques. The detectors include internal communications interfaces so they are easy to read. Different interfaces, including wired, e.g. USB ports, and wireless interfaces, may be used, so that the dosimeters may be read over the internet. The detectors can thus be deployed or used in a variety of detection systems and screening methods, including periodic or single time screening of people, objects, or containers at a location by means of affixed dosimeters; screening of objects, containers or people at a series of locations by means of affixed dosimeters, and surveillance of an area by monitoring moving dosimeters affixed to people or vehicles.

Abstract: A phantom for quality monitoring of a medical system, in particular a medical therapy system, or particle therapy system, is described. The phantom has a fixation device for coupling the phantom to a positioning device. In an aspect, a method for quality monitoring in a medical system, in particular a medical therapy system or particle therapy system is described, in which such a phantom is coupled via a fixation device to a positioning device and, with the aid of the positioning device, is brought to a predefined position. In another aspect, a particle therapy system has a treatment chamber, with a positioning device to which a phantom can be coupled so that the phantom can be brought to a predefined spatial position using the positioning device.

Abstract: Radiation dosimeters that are based on carbon materials such as carbon powder, carbon fibers, carbon nanoparticles and carbon nanotubes are developed. The dosimeter may contain a singular element or multiple sensing elements that are arrayed in 1-D, 2-D and 3-D formations. Each sensing element is made up of two electrodes with carbon materials deposited between the electrodes. The sensing elements may be deposited on flexible substrates to create flexible dosimeters. In addition, the carbon sensing materials may be deposited onto transparent substrates to achieve a transparent dosimeter. Transparent and/or flexible dosimeters can be fabricated with the carbon materials. The sensing elements are connected to external power sources. As the elements are exposed to radiation beams, the change in resistivity or conductance of the carbon materials is measured by current detection circuitry.

Abstract: A portable X-ray detector unit includes a portable, hand-held cassette having exposure detection fields for measuring the level of radiation to which a subject to be imaged is exposed. An Automatic exposure control terminates radiation supplied to a subject when it is determined that the level of exposure exceeds a predetermined threshold as interpreted in the portable detector unit. A user-interface is provided to control the exposure detection fields and/or the automatic exposure control.

Abstract: The monitoring of UV radiation has received increased attention recently due to the hazards of accelerated skin ageing and even cancer following excessive exposure. Personalized monitoring gives a more accurate reading than crude weather forecasts of the ‘UV index’. This invention answers both these needs in a personal UV monitor that is incorporated into an existing display. Minimal processing changes are made to an existing display in order to achieve this added functionality, which is therefore achieved at little additional cost.

Abstract: Bidimensional dosimetric detector, comprising: a monolithic base-matrix (1) made of homoepitaxial silicon with a surface for exposition to the radiation, a plurality of radiation-sensible junction diodes (2) for producing a plurality of electrical signals in response to the radiation, electrical terminals (3) connected to said diodes for feeding said produced electrical signals to an acquisition and processing unit (5), wherein the perimeter of one or more said diodes is defined by a boundary region of the electrical field of same diode.

Abstract: A radiation detector of the ?E-E type is proposed.

Abstract: An in-vivo dose detector (41) for an HDR brachytherapy system (1; 31), wherein the detector is insertable into and movable through a catheter (15), and comprises a sensor (53) operable to detect radiation from a source (52) used to irradiate a tissue to be treated (9) in the course of an HDR brachytherapy treatment. A brachytherapy system and a method of dose monitoring are also disclosed.

Abstract: A radiation detector of the ?E-E type is proposed.

Abstract: A two-dimensional array of memory cells may be used to implement a spatial dosimeter. The two-dimensional array of cells may be implemented by an integrated circuit memory Because of the relatively small size of the integrated circuit memory, the resolution of the resulting array may be less than 100 nanometers. The change in threshold voltage of each of the cells, as a result of radiation exposure, may be used to calculate the dose seen at each cell, allowing dose profiles in two dimensions with sub-micrometer resolution.

Abstract: This invention relates to a system for determining a biodistribution of radioactive agents in a subject. According to the invention, a detector system comprising two or more detectors arranged to be attached to the subject at localized areas is used for detecting the radiation emitted from the imaging agents at localized tissues within the subject. The measuring results in separate radiation data sets associated to the tissues. The detectors are further being arranged to adapt the measuring rate to the pharmacokinetic behavior of the tissues in order to capture all relevant data points. A processor then uses the data sets for determining the radioactivity within each respective tissue and based thereon the biodistribution within the subject.

Abstract: A radiation sensor array is carried on a flexible sheet of film, for placement on the skin of a patient adjacent to a brachytherapy location beneath the skin. With the array approximately centered on a position where radiation source to skin distance is estimated to be minimum, the array of sensors is used to monitor radiation dose received at the skin. With a controller connected to the array and preferably also to the radiation source in the applicator, the radiation dose received at all skin points of interest can be monitored, a point of maximum dose and a projected approach to limit dose can be calculated, and in response the system can warn the operator or control a brachytherapy procedure so as to discontinue radiation or control the radiation level or source position in real time. The system can also include percutaneous sensors.

Abstract: A miniaturized floating gate (FG) MOSFET radiation sensor system is disclosed, The sensor preferably comprises a matched pair of sensor and reference FGMOSFETs wherein the sensor FGMOSFET has a larger area floating gate with an extension over a field oxide layer, for accumulation of charge and increased sensitivity. Elimination of a conventional control gate and injector gate reduces capacitance, and increases sensitivity, and allows for fabrication using standard low cost CMOS technology. A sensor system may be provided with integrated signal processing electronics, for monitoring a change in differential channel current ID, indicative of radiation dose, and an integrated negative bias generator for automatic pre-charging from a low voltage power source. Optionally, the system may be coupled to a wireless transmitter. A compact wireless sensor System on Package solution is presented, suitable for dosimetry for radiotherapy or other biomedical applications.

Abstract: A microdosimeter, comprising an array of three-dimensional p-n junction semiconductor detectors, each providing a sensitive volume-target and a tissue equivalent medium for generating secondary charged particles. The array is manufactured from a semiconductor on insulator wafer and the detectors are located to detect secondary charged particles generated in the tissue equivalent medium.

Abstract: Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes insitu polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out.

Abstract: An array-based C-MOS sensor device is provided with a facility for on the basis of non-destructive cell readout generating a radiation dose-sensing signal. In particular, the facility is arranged for accessing a subset of multiple distributed C-MOS cells across the array and feeding by such accessed cells an algorithmic means for therein generating an overall feedback dose control signalization and/or an over-all trigger signalization.

Abstract: The present invention is related to a water phantom for measuring and determining the dose distribution of radiation produced by a particle beam or photon radiation beam comprising: a water tank, the water tank having a lower base and side walls; supply means for supplying water to the water tank. The water tank comprises an intermediate base that forms, together with side walls and said lower base, a closed lower tank underneath said intermediate base and an upper tank above said intermediate base, the closed lower tank being connected to the supply means and allowing the flow of water toward said upper tank through a plurality of water admission passages defined in the intermediate base to provide an unturbulent water flow within said water tank 2.