Abstract: A person intervening on the site is fitted with a plurality of radioactivity meters (1, 2, 3, 4, 11, 12) distributed over the body at locations such that at least two meters receive radiation doses that are different due essentially to the screen constituted by the body of the intervener, and the radiation doses received simultaneously by the meters are compared to deduce therefrom information concerning the direction towards the source relative to the intervener.

Abstract: An improved apparatus for collecting and analyzing an airborne particulate radionuclide having a filter mounted in a housing, the housing having an air inlet upstream of the filter and an air outlet downstream of the filter, wherein an air stream flows therethrough. The air inlet receives the air stream, the filter collects the airborne particulate radionuclide and permits a filtered air stream to pass through the air outlet. The improvement which permits real time counting is a gamma detecting germanium diode mounted downstream of the filter in the filtered air stream. The gamma detecting germanium diode is spaced apart from a downstream side of the filter a minimum distance for a substantially maximum counting detection while permitting substantially free air flow through the filter and uniform particulate radionuclide deposition on the filter.

Abstract: A vehicle imaging system for producing an integrated video image of a scene about a vehicle. The system includes sensors for detecting radiation in the range of wavelengths of 250 nm to 12 .mu.m. The radiation sensors transmit signals to a video mixer to produce an image of the scene in a display assembly. The display assembly may also incorporate information from a RADAR receiver as well as navigational data.

Abstract: A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacting a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.

Abstract: A cone-tipped penetrometer for in situ analysis of soil or sediment by X-ray fluorescence spectroscopy. Rather than using a radioactive source, a miniature x-ray tube is powered by a filament isolation transformer located inside the penetrometer pipe which has an outside diameter of about 2 inches or less. The x-rays pass out through a special x-ray transmissive window, such as a low metal impurity-containing high strength boron carbide, into the soil or sediment below the surface and the resulting x-rays from the metals in the soil or sediment return through the window to a detector. The signal is transmitted back up to the surface where the x-rays are quantitatively analyzed to determine the concentration of metals in the soil. This real-time in situ x-ray fluorescence spectroscopy of soil or sediment samples permits field analysis of hazardous waste sites and other underground soil and underwater sediments.

Abstract: Capillary pressure curves can be derived from nuclear magnetic resonance (NMR) pore size distributions. These derived capillary pressure curves can be used to derive the displacement pressure, the fractional bulk volume of mercury at infinite pressure and a geometrical factor. These factors can be used to accurately predict permeability from an NMR derived capillary pressure curve.

Abstract: A method of detecting an object in an examination zone is well-suited for detecting land mines buried in the soil. The mean atomic numbers of the object is different from that of the examination zone. The examination zone is irradiated by gamma radiation. The annihilation radiation thus generated is measured and evaluated. The gamma radiation, which is sufficiently strong to generate electron-positron pairs, amounts to less than 10 MeV. The radiation generated in the examination zone by the gamma radiation beam is detected by a plurality of detector elements, which are arranged in such a manner that they can always detect only a respective segment of the gamma radiation beam.

Abstract: A mobile robotic system that conducts radiological surveys to map alpha, beta, and gamma radiation on surfaces in relatively level open areas or areas containing obstacles such as stored containers or hallways, equipment, walls and support columns. The invention incorporates improved radiation monitoring methods using multiple scintillation detectors, the use of laser scanners for maneuvering in open areas, ultrasound pulse generators and receptors for collision avoidance in limited space areas or hallways, methods to trigger visible alarms when radiation is detected, and methods to transmit location data for real-time reporting and mapping of radiation locations on computer monitors at a host station. A multitude of high performance scintillation detectors detect radiation while the on-board system controls the direction and speed of the robot due to pre-programmed paths.

Abstract: The present invention relates to a soil anslysis system for determining various soil characteristics. Various soil characteristics may include moisture content, organic matter content and the presence of nitrogen phosphate, potassium and other elements. The soil analysis system includings a plurality of testing assemblies for determining soil characteristics. The soil analysis system further includes a soil testing device or probe which is operatively inserted into the soil to support the testing assemblies. Preferably, the soil analysis system is used in cooperation with a positioning system and a data collection system for recording soil characteristic data based upon the geographic location to which the soil characteristic data relates.

Abstract: The invention is based in part on the discovery that a plastic housing that is lightweight is surprisingly efficient inasmuch as background signals from any gamma radiation are significantly reduced by using a plastic housing instead of a metal housing. A further aspect of the present invention is the profile of the housing as a bi-linear approximation to a parabola resulting in full optical response from any location on the scintillation material to the photomultiplier tube. A yet further aspect of the present invention is that the survey probe is resistant to magnetic fields. A yet further aspect of the present invention is the use of a snap-fit retaining bracket that overcomes the need for multiple screws.

Abstract: Radiological surveys for the discovery and mapping of subterranean fossilized relics, notably dinosaur bones utilize a detector shielded by a lead casing having a collimating window oriented approximately parallel and slightly above ground surface to receive gamma radiation traveling approximately vertically upward.

Abstract: Method and apparatus for determining the presence and identity of predetermined gases in the atmosphere such as would be found on a natural gas, natural gas liquid or oil pipeline if such pipeline was subject to leakage. An infrared transmitter and an infrared receiver are each mounted on a movable platform such as a fixed or rotary wing aircraft or on a vehicle. As the moving platform follows its predetermined assigned route, the presence of gases is determined by the infrared transmitter and receiver and at least one data acquisition module. The geographic position of the movable platform is determined so that the geographic location of the predetermined gases in the atmosphere is known.

Abstract: A system for the in-situ detection of chemicals, including water, in soil comprises: a penetrometer for penetrating the soil, the penetrometer including interior and exterior surfaces, and a window for allowing infrared radiation to be transmitted between the interior and exterier surfaces of the penetrometer; a driver for driving the penetrometer into the soil to a plurality of different depths; a source for providing infrared radiation which passes through the window to irradiate the soil adjacent to the window; an infrared transmitting chalcogenide optical fiber; an optical system disposed within the penetrometer adjacent to the window for transmitting infrared radiation from the source through the window into the soil and for collecting infrared radiation reflected from the soil back through the window into a first end of the chalcogenide fiber; and a spectrometer coupled to a second end of the infrared transmitting chalcogenide optical fiber for receiving and analyzing the reflected infrared radiation pa

Abstract: The present invention provides a new method to determine corrected characteristics of materials using the measured quantities obtained by a measurement and an extensive set of database points representing laboratory and modeled results in well defined environments. In particular the invention relates to the measurement of the characteristics of the formation around a wellbore as well as of the borehole with a well logging tool. Using a dynamic parametrization technique, the environmental corrections and the transformations from the measured to the physical characteristics can be achieved in a more accurate, robust and flexible way. The dynamic local parametrization is based on a weighted multiple linear regression over the entire database to obtain the local coefficients for the transformation which can be expressed as a simple equation.

Abstract: A penetrometer sensor probe and system with a detachable sleeve section which performs radiation measurements in subsurface formations. The penetrometer sensor probe measures radiation particularly gamma radiation in real time as the sensor probe is retrieved from a subsurface formation following an initial penetrometer push operation. A sacrificial sleeve surrounding the sensor probe's radiation detector is separated from the penetrometer after an initial push operation at a particular subsurface depth. During a retraction process, a sleeve section containing the radiation detector is detached from the sacrificial sleeve of the penetrometer. The sleeve provides both strength to the penetrometer and protects the probe's radiation detector from damage. Additionally, the detachable sleeve results in significantly reduced bremsstrauling scattering radiation attributed to gamma radiation that otherwise would strike a steel casing adjacent to the radiation detector.

Abstract: A system for assistance in landing a helicopter and for the detection of electro-magnetic anomalies utilizing helicopter blades as carriers of receiving devices in a wide spectrum of electro-magnetic fields with a predicted sensitivity and resolution far in advance of previous systems.

Abstract: A method of surveying a surface to determine the existence of a radiation source, e.g., a radioactive source, providing a procedure for determining an optimum scan velocity for scanning past a source so as to provide the required degree of confidence to detect the presence of radiation sources while avoiding false source detection. A first scan velocity is selected based upon detector information and the nature of the survey surface, following which spreadsheet-type calculations are made based upon the expected maximum source count rate, background rate and the selected velocity. The spreadsheet calculations provide an indication of the confidence of distinguishing source activity from background radiation at the selected scan velocity. The indicated confidence is compared to the required confidence level, and when the indicated confidence is not optimally close to the required confidence, another scan velocity is selected and the spreadsheet calculations are repeated.

Abstract: A radon test package of simplified and low cost construction. A generally flat outer packet is formed from a single sheet of radon barrier material folded to define two panels with facing inner surfaces sealed along side edge portions, leaving a closeable open edge portion. The outer packet is expandable so as to define a chamber, having an access opening corresponding to the open edge portion. The facing inner surfaces have a surface layer of fusible low density polyethylene, and a sheet of gas-permeable kraft paper is adhered by heat sealing directly to the inner surface of one of the panels in an adhesion pattern which defines a closed triangular pocket containing activated charcoal. When the packet is expanded, the access opening is square, and a block of open cell foam material is inserted to maintain the opening in a standardized configuration, as well as to eliminate the effect of air currents.

Abstract: A casing-less down hole sampling system for acquiring a subsurface sample for analysis using an inductively coupled plasma system is disclosed. The system includes a probe which is pushed into the formation to be analyzed using a hydraulic ram system. The probe includes a detachable tip member which has a soil point mad a barb, with the soil point aiding the penetration of the earth, and the barb causing the tip member to disengage from the probe and remain in the formation when the probe is pulled up. The probe is forced into the formation to be tested, and then pulled up slightly, to disengage the tip member and expose a column of the subsurface formation to be tested. An instrumentation tube mounted in the probe is then extended outward from the probe to longitudinally extend into the exposed column. A balloon seal mounted on the end of the instrumentation tube allows the bottom of the column to be sealed.

Abstract: A probe device for in-situ detection of contaminants such as petroleum prcts in a subsurface media such as soil. The device comprises an elongated probe housing which is driven into the media. An ultraviolet lamp located in the housing provides excitation energy which is reflected through a UV transparent window in the housing to the media by at least one reflecting element in the housing. The reflecting element allows longitudinal offset of the lamp from the window providing space for high intensity UV lamps. A radiation receiver receives fluorescent radiation emitted from contaminants in the media transmitted through the window and provides a signal for analysis equipment on the surface. A concentrating reflector between the lamp and the housing and a focusing lens between the lamp and the reflecting element collect and focus excitation energy from the lamp.

Abstract: A system for determining depth profiles of concentrations of hazardous elements in soils comprises a neutron source for generating neutrons of a first energy level and irradiating a volume of soil with the neutrons. Nuclear reactions are effected within the soil and gamma radiation is emitted from the soil. The system also includes an array of gamma detectors for detecting gamma radiation emitted from the soil; source electronics for controlling the width of regularly repeated pulses of neutrons generated by the neutron source; detector electronics associated with the gamma detectors for amplifying and digitalizing signals generated by the gamma detectors and storing data representing the digitalized signals; spectral analysis software for analyzing the data and determining the concentrations of selected target elements in the soil; and an acquisition interface module (AIM).

Abstract: A method of determining the concentration of incombustible material in a predetermined volume of coal includes irradiating the volume with .gamma.-rays from a first source having a first, low energy; and simultaneously irradiating the volume with .gamma.-rays from a second source having a second, higher energy. Rays of back-scattered radiation from the irradiated volume are detected. An analogue signal for each ray that is detected is generated, an amplitude of said signal being representative of the energy of the ray. Each analogue signal is converted into an equivalent digital signal. For all values of signals in a predetermined range, the number of digital signals having the same value that are detected in a predetermined time period is determined and said signals of the same value are stored together to provide a frequency spectrum. The frequency spectrum is processed to provide the concentration of incombustible material in the volume.

Abstract: A photoneutron detection apparatus comprises an X-ray generator and a neutron detector adapted for placement in proximity to subsurface soil. The X-ray generator produces timed pulses of X-ray photons having a range of electronically controlled energies which penetrate the subsurface soil to produce photoneutron emissions that are received by the neutron detector. The neutron detector generates a signal representative of the neutron flux. A signal analysis system time correlates the signal with the timed X-ray pulses to determine the presence of selected contaminants.

Abstract: A radon detector employs an electrically charged pressed, porous metal filter that allows radon gas diffusion, while blocking ambient light, so that it readily traps both attached and unattached Po-214 and Po-218 ions, that may be present in gas passing through the filter, the filter being charged positively relative to an unbiased PN junction of a photodiode detector within a detection chamber. As a consequence, radon daughter products are prevented from corrupting the radon measurement. Since no voltage differential is applied across its PN junction, the photodiode detector operates in a photovoltaic mode, which avoids the problem of Schottky noise, producing low amplitude current pulses, which are amplified, passband filtered, and thresholded to provide well-defined pulses that are counted over a given measurement interval and converted to radon concentration in terms of picocuries per liter.

Abstract: A system for making airborne surveys uses first and second surveys made at opposite points on the thermal cycle and collects hyper-spectral image data forming continuous bands in the visible, solar infrared and thermal infrared regions.

Abstract: An on-the-go probe for determining the presence of chemical residue in a soil using Transient Infrared Spectroscopy by pulling a soil implement through the soil with the soil implement having a heating or cooling source for temporarily creating a temperature differential between a layer of soil proximate the soil implement and a layer of soil remote from the soil implement, and moving the soil sufficiently fast with respect to heating source to enable measuring the radiation characteristics of the thin layer of soil before the thin layer of soil begins to self-absorb and substantially change its emission characteristics.

Abstract: A method for airborne surveying is disclosed to acquire, process and calculate the apparent thermal inertia of earth surface materials during flight and by post-flight processing. Two separate airborne surveys are conducted during a diurnal solar cycle to determine the maximum and the minimum radiant temperatures of the earth surface materials. The albedo of the earth material is determined and is used to calculate the apparent thermal inertia of the earth surface materials. Spatial rectification of the two surveys is accomplished by use of differential global positioning.

Abstract: A method for detecting flaws in structures using dual band infrared radiation. Heat is applied to the structure being evaluated. The structure is scanned for two different wavelengths and data obtained in the form of images. Images are used to remove clutter to form a corrected image. The existence and nature of a flaw is determined by investigating a variety of features.

Abstract: A chlorinated hydrocarbon sensor is substituted as a portion of a cone perometer. The sensor includes a titanium casing in which a cylindrical sleeve of beryllium alpha target material is fixed. A rod-shaped americium alpha particle source is disposed within the casing and is moved by an electromagnetic relay into an interacting state in which the beryllium sleeve encases the americium alpha particle source. The interfacing beryllium and americium emit high energy neutrons used to detect the chlorinated hydrocarbons. The emission takes place only when an electromagnetic relay is energized so that cessation of energy will cause a cessation of neutron generation. The rod-shaped alpha particle source will then be withdrawn from the cylindrical beryllium sleeve by a retracting spring. The generated neutrons interact with hydrogen and chlorine in the soil surrounding the sensor to produce characteristic gamma radiation that is detected and measured by a sodium iodide scintillation crystal.

Abstract: A method for determining the depth of a gamma emitting element beneath the surface of a volume of soil is disclosed. The disclosed method includes the steps of detecting gamma rays at a first height h.sub.1 above the surface; detecting gamma rays at a second height h.sub.2 above the surface; determining a ratio R representative of the ratio of the number of gamma rays detected at h.sub.2 to the number of gamma rays detected at h.sub.1, or vice versa; and inferring, on the basis of the ratio R, an estimate of the depth of the gamma emitting element beneath the surface.

Abstract: An improved method for detecting, measuring, and distinguishing crop residue, live vegetation, and mineral soil. By measuring fluorescence in multiple bands, live and dead vegetation are distinguished. The surface of the ground is illuminated with ultraviolet radiation, inducing fluorescence in certain molecules. The emitted fluorescent emission induced by the ultraviolet radiation is measured by means of a fluorescence detector, consisting of a photodetector or video camera and filters. The spectral content of the emitted fluorescent emission is characterized at each point sampled, and the proportion of the sampled area covered by residue or vegetation is calculated.

Abstract: A elecret substrate (10), which is exposed to the environment so as to collect molecular contamination, lies at the bottom of a holder (20). Above the substrate a sensor head (100) is supported. Signals from the sensor head are relayed to an electrostatic voltmeter (130). The voltage reading at electrostatic voltmeter (130) is a function of the amount of polar molecule contamination on substrate (10).

Abstract: Apparatus for helping predict the occurrence of an earthquake or a volcanic eruption by detecting and recording the direction of a neutron flow generated in the earth's magma and the intensity of the neutron activity.

Abstract: A device for detecting radiation within a pipe having one or more carriages adapted for movement through the pipe. A set of radiation sensors is mounted on each carriage for detecting radiation on the interior of the pipe. The radiation sensors are positioned to cover a complete circumferential strip on the pipe interior while maintaining the geometry required to meet U.S. government criteria for the unconditional release of the pipe. Readings from the radiation sensors are transmitted out of the pipe and recorded to establish a detailed radiological survey of the pipe interior.

Abstract: A radiation-sensing assembly adapted for sensing radiation emitted from a source of radiation which may be non-coal layers (shale and other materials) in a coal mine tunnel. The sensor assembly incudes a housing forming an enclosure for a radiation-sensing medium. A cover is provided on the top of the lower portion of the housing, and radiation passes through the cover to impinge on the sensing machine. The cover includes a collimator, which is built into the cover, to direct the radiation from the source to the sensing medium.

Abstract: An apparatus for conducting radiologic surveys. The apparatus comprises in the main a robot capable of following a preprogrammed path through an area, a radiation monitor adapted to receive input from a radiation detector assembly, ultrasonic transducers for navigation and collision avoidance, and an on-board computer system including an integrator for interfacing the radiation monitor and the robot. Front and rear bumpers are attached to the robot by bumper mounts. The robot may be equipped with memory boards for the collection and storage of radiation survey information. The on-board computer system is connected to a remote host computer via a UHF radio link. The apparatus is powered by a rechargeable 24-volt DC battery, and is stored at a docking station when not in use and/or for recharging.

Abstract: A fan-less long range alpha detector which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces.

Abstract: Organically contaminated earth-bound material is treated in-situ by positioning one or more x-ray converters in chambers formed in an earth and/or water site containing such earth-bound material and irradiating the contaminated material in-situ adjacent to each chamber with x-radiation from the x-ray converter to decompose the organic compounds. A high energy electron beam from a electron beam source is directed to the x-ray converter to produce the x-radiation. The electron beam source, such as a linear induction accelerator or an RF linear accelerator may be positioned either within the chamber near the x-ray converter or above ground.

Abstract: A method and apparatus for remote detection of an oil slick at or near the surface of the water using a combination of two or more ultraviolet lasers and comparing the relative magnitude of the received Raman backscattering signal magnitudes to determine the existence of the oil slick. The use of two different laser frequencies provides for elimination of atmospheric transmission variations and wave modulation.

Abstract: A high-energy radiation survey system capable of imaging and determining the distances of, sources of incident radiation and of determining the energy of such radiation, incorporating a shaped radiation detector shield and detector configured therein for low-noise collimation of the radiation for directional mapping. The system is capable of being mounted on a remotely controllable vehicle and of being operated from an operator's station remote from radiation hazards. The system can be used to generate high resolution radiation dose maps superimposed on a real-time video image of a room or other areas in nuclear power plants and other facilities using radioactive material.

Abstract: A vadose zone monitoring system for detecting leaks from a contaminant storage facility or the like is disclosed in which leaks are detected in a confined radial area around at least one generally horizontal, neutron access tube disposed under the landfill. A wicking layer of material increases the leakage detection coverage area by laterally transmitting leakage to the access tube via capillary action. A clay liner may be disposed between the landfill and wicking layer for controlling the rate of leakage to prevent build-up of a pressure head large enough to force liquid through the wicking layer before it is conducted laterally to the access tube. Leak detection may be carried out by neutron moderation techniques or other moisture detection schemes for developing logs indicative of the leakage from the landfill. The wicking layer permits an entire network of access tubes or other leak detection means to be installed under substantially the entire landfill for monitoring leaks therefrom.

Abstract: A geophysical survey system including a remotely piloted vehicle, a geophysical sensing payload mounted thereon and ground based control and data receiving means.

Abstract: Methods for distinguishing among oil samples, and more particularly between a fluid containing oil base mud and formation oil samples are described. The methods all rely on the discovery that the optical absorption spectrum of all crude oils in the visible and near infrared spectra can be described according to the equation OD=ae.sup.Eb, where (OD) is a measured optical density, (b) is a value between 0.37 and 0.55 chosen according to the wavenumber (E) and can be chosen as a constant equal to 4.6.times.10.sup.-4 cm, and (a) is an unknown which classifies the crude oil. By making measurements and solving for (a), a crude oil can be classified. In a flow stream which has a changing oil content, such as may be obtained by a borehole tool which obtains fluid samples from the formation, by monitoring the unknown (a), a determination may be made as to when a formation oil is being obtained as opposed to a mud filtrate.

Abstract: A method of analysis of rock samples taken from the bore of a well being drilled or from the Earth's surface and performed upon the apatite grains contained within the samples. The apatite grains are separated from the surrounding rock, polished to expose internal surfaces, and etched with acid to reveal the presence and characteristics of fission tracks within the apatite to determine the geological characteristics of the apatite. The grains containing the apatite are viewed under an optical microscope or other imaging apparatus and apatite crystals or crystal fragments which contain etched fission tracks are selected for analysis. If selected for analysis, measurements may be taken to determine the size and shape of the etched pits intersecting the apatite grain surface. The measurements are taken using a digitizing apparatus interconnected to a computer and containing a point light source superimposed upon the apatite grains viewed through the microscope.

Abstract: This invention provides method and apparatus to predict accurately volcanic eruptions or the occurrence of earthquakes without the use of a seismometer or an incline level meter. The apparatus includes a neutron sensor, a counter and a displaying device to indicate an integrated count number or changes in count number of neutrons radiated from the earth's magma with the prediction being performed on basis of the changing count or integrated count number for a given period of time.

Abstract: A system for remotely detecting liquid contaminants on surfaces, including hemical agents and their simulants is presented. The system includes a Fourier Transform Infrared Spectroradiometer aligned to optionally develop graybody photoluminescence spectra from the generation of a plurality of interferograms co-added to provide a favorable signal to noise ratio for use with and thereafter transforming the co-added interferograms. A laser is used for surface irradiating a substrate potentially having the chemical agents to heat the substrate. A shutter controls the laser to receive and record photoluminescence emissions from the heated substrate, and generate a plurality of interferograms co-added to provide a favorable signal to noise ratio for use with the Fourier Transform Infrared Spectroradiometer. The co-added interferograms are used to generate molecular absorption resonant peaks which are mathematically processed in the Fourier Transform Infrared Spectroradiometer.

Abstract: This invention relates to the field of prospecting to locate mineral deposits particularly gravel and clay deposits. The method of prospecting to locate these mineral deposits includes the steps of traversing an area of the earth's surface and obtaining measurements of gamma radiation corresponding to the presence of uranium, potassium and thorium at spaced points along the traverse. The data collected are used to determine an area mean value for the gamma radiation measurements obtained. The mineral location is obtained by noting areas within the area traversed in which the variations of the measurements of gamma radiation corresponding to each of uranium, potassium and thorium relating to the respective area mean values are indicative of the particular mineral being located.

Abstract: A spectroscopic method to rapidly measure the presence of plutonium in soils, filters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium and .gamma.-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n-type germanium spectrometer which is equally efficient for the detection of low-energy x-rays (10-2000 keV), as well as high-energy .gamma. rays (>1 MeV). A 8192- or 16,384 channel analyzer is used to acquire the entire photon spectrum at one time. A dual-energy, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, and detector resolution. The L x-ray portion of each spectrum is analyzed by a linear-least-squares spectral fitting technique. The .gamma.

Abstract: A system for determining the health risk, due to alpha emitters attached to particles of various sizes, these alpha emitters being due to the level of radon, to persons within an environment where radon may be present. In one embodiment, a sample of air is passed through a filter element having a collection characteristic such that essentially all particulate material, with their associated radon progeny, is removed from the air. The alpha particles emitted by the decay of these radon progeny are detected with an appropriate alpha particle spectrometer. The realtime resolving of the energies of individual of the daughter atoms permits a determination of the working level or PAEC associated with the radon. In those instances where lung dose is to be determined, the filter element has two portions. The first portion is designed to remove particles in a manner like that which occurs in the human nasal passage.

Abstract: An automatically processed alpha-track radon monitor is provided which includes a housing having an aperture allowing radon entry, and a filter that excludes the entry of radon daughters into the housing. A flexible track registration material is located within the housing that records alpha-particle emissions from the decay of radon and radon daughters inside the housing. The flexible track registration material is capable of being spliced such that the registration material from a plurality of monitors can be spliced into a single strip to facilitate automatic processing of the registration material from the plurality of monitors. A process for the automatic counting of radon registered by a radon monitor is also provided.