Abstract: A portable monitoring system for detecting a radiated electrostatic field and producing an audible warning when the detected field exceeds a selected value is characterized by a switching device which can be used to reset the threshold warning level and which is not affected by the hand proximity effect. An alarm is sounded when a signal corresponding to the detected field exceeds a value which is stored. The stored value can be reset by a manually operated switching circuit including a delay device operable to delay the storage of a reference level corresponding to the intensity of the field currently detected.

Abstract: An instrument for measuring levels of concentration of tritium and tritium oxides in environmental air includes a scintillation detector, such as a photomultiplier, and a controlled device for exposing scintillators to the detector in succession. Air being monitored is passed over the scintillators. A thermoelectric device is used to cool and warm one of the scintillators for condensing air moisture onto its surface and for evaporating moisture from it, the count rate being measured in both instances. The other scintillator is a reference scintillator, the count rate from which is also measured, and a measurement is taken with neither of the scintillators exposed to the scintillation detector. The concentration levels of tritium and tritium oxides are computed from the set of measurements.

Abstract: An electric field strength indicator for use with high voltage conductors comprises a capacitive probe mounted within a tubular shield having an insulating spacer at one end for locating the unit with respect to a conductor under test. The probe is electrically coupled to a signalling circuit and is movable axially within the shield to a position at which a threshold response is obtained. Such position, which denotes the conductor voltage, is read on a scale provided. Because of the shield the device is directional, the probe being shielded from neighboring conductors.