Abstract: A method of monitoring radioactive emissions which includes obtaining a data set, the data set including a record of an event together with an indication of the time of the event and/or the detector which detected the event. The method also includes processing the data set by analyzing the whole of the data set according to a first set of criteria to provide a first analysed data set and analysing the whole of the data set according to a second set of criteria to provide a second analysed data set, one or more criteria of the second set being different to the criteria of the first set. The first set of criteria and the second set of criteria both include a first time period and a second time period.

Abstract: A method of collecting data on radioactive material includes: positioning a detector unit at a first position relative to the environment; collecting at least a part of a first set of data from a first position using a detector unit; and collecting at least a part of one or more subsequent sets of data on the environment from one or more subsequent positions using the detector unit; wherein one or more of the subsequent positions is determined, at least in part, by considering at least a part of the data of one or more of the sets of data previously collected. The subsequent positions are determined so as to improve the information on the radioactive material provided as a result of the data collected from that position.

Abstract: Monitoring radioactive emissions includes providing a processor having a plurality of potential data input channels, providing data input to the processor the potential data input channels, that data input being generated by an instrument, and combining all the data inputs in the processor. The processor is configured to handle data input from at least two of each of the following groups: (i) a gamma detector, a low resolution gamma detector, a high resolution gamma detector, a beta detector, an alpha detector, an ion detector, an X-ray detector, a neutron detector, a detectors responding to passive emissions, a detector responsive to active emissions, a detector responsive to a transmission source; and (ii) a distance measurer, such as a range finder, a visual radiation detector, such as a still camera and/or digital camera and/or video camera, a measurer of weight, a measurer of mass, a measurer of size.

Abstract: A method of obtaining information about radiation arising from within an environment includes providing a directionally sensitive radiation detector which has a field of view and providing a visual image capturing device which has an area of vision. The radiation for a field of view is measured, the field of view including a part of the environment. The measurement of radiation is recorded together with an indication of the space or position of the respective field of view relative to the detector. A visual image of an area of vision is obtained, the area of vision including the part of the environment within the field of view. The image is recorded together with an indication of the spatial position of that field of view relative to the detector. Selecting the set of data from the measurement of radiation according to a criteria set after completion of the measurements of radiation. The information is overlaid from one or more of the measurements of radiation with one of the visual images.

Abstract: A method and apparatus are provided for determining radiation dose rates at selected locations within an environment. Incident gamma ray energy and count rate are measured at one or more measured locations within the environment to obtain a measured spectrum for those measured locations. The spatial position of the measured locations is also measured. An emitted spectrum is then determined for the measured locations based on the measured spectrum. The emitted spectrum may then be used to determine the dose rate at one or more selected locations (which may be different than the measured locations). In this way the invention provides an accurate solution for the dose rate at any point of interest within the environment based on the measured count and incident energies.

Abstract: An event monitoring system has a plurality of detector units for detecting neutrons or other emissions from radioactive materials (i.e., events). At least one of the detector units has a detector for the events and an amplifier to amplify signals generated by the detector. A signal handler receives the amplified signals and an adder adds to the signals an indication of the detector unit from which the signals originated. A combiner combines the signals. A serial link conveys the combined signals from the signal handler to a signal processor which includes a signal receiver for the combined signals. A time stamper applies to the signal an indication of time of the generation of the signal by the detector unit, and a computer processes the signals, including the time and detector unit indications, using software to produce information on the signals or events they represent.

Abstract: A method and apparatus are provided for determining radiation dose rates at selected locations within an environment. Incident gamma ray energy and count rate are measured at one or more measured locations within the environment to obtain a measured spectrum for those measured locations. The spatial position of the measured locations is also measured. An emitted spectrum is then determined for the measured locations based on the measured spectrum. The emitted spectrum may then be used to determine the dose rate at one or more selected locations (which may be different than the measured locations). In this way the invention provides an accurate solution for the dose rate at any point of interest within the environment based on the measured count and incident energies.

Abstract: The invention provides improved methods and apparatus for investigating emissions from radioactive sources within an environment. In particular, the method deploys a collimated detector to scan the environment and obtain approximate position information on sources within that environment together with further investigations using a moveable shielding component which is moved relative to the field of view of the collimator. In an alternative technique, the collimator is moved in two different directions to achieve positional information using scanning.

Abstract: A method and apparatus are provided for determining radiation dose rates at selected locations within an environment. Incident gamma ray energy and count rate are measured at one or more measured locations within the environment to obtain a measured spectrum for those measured locations. The spatial position of the measured locations is also measured. An emitted spectrum is then determined for the measured locations based on the measured spectrum. The emitted spectrum may then be used to determine the dose rate at one or more selected locations (which may be different than the measured locations). In this way the invention provides an accurate solution for the dose rate at any point of interest within the environment based on the measured count and incident energies.

Abstract: A logic circuit monitors the outputs of R, F and T probability generators, provides an output pulse, and increments or decreases a counter, the output of which is fed back to the T probability generator. R represents the rate or frequency of a random background, F represents the fraction of events in the random background R that will have associated coincident pairs, and T a respective die-away time. The parameters R, F and T are decided by the user. Such a pulse generator may simulate the output from a neutron well, and may be used to test neutron coincidence systems in a simple and rigorous manner.

Abstract: A calorimeter is disclosed comprising a sample chamber (12) adapted to enclose a sample, a thermally conductive reference surface (14) surrounding and insulated from the sample chamber (12) and a casing (16) surrounding and insulated from the reference surface. Temperature transducers, in communication with a micro-computer, record the temperatures of the sample chamber (VS) and reference surface (V1) at periodic intervals. The micro-computer is programmed to calculate the theoretical temperature (VT) of the sample chamber from the measured values of the temperature of the reference surface (V1) and estimated values of the thermal power of the sample (I), the thermal resistance from the sample to the sample chamber (RS) and the thermal capacity of the sample (CS), and to optimize the fit between the theoretical calculations (VT) and the corresponding measured values (VS) of the temperature of the sample chamber.