tritium surface activity monitor

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No more scintillation measurement time delays.

Smearing or wiping, is the most common and reliable method of determining tritium surface contamination in pipes, on the surfaces of drums, gloveboxes, laboratory benches, or any other device that may have tritium contamination on surfaces.  A smear is normally measured by dissolving the smear paper in a "cocktail", putting it into a vial and measuring disintegrations in a scintillation counter. There are subsequent problems associated with storage of the active liquid and cleaning the apparatus. The scintillation counter is known to be an accurate instrument, but because making a smear sample is less accurate, it is the efficiency of creating the smear that controls the overall accuracy of the process.

Tyne Engineering has developed an instrument that overall is as accurate as the scintillation counter for reading smears. The Tritium Surface Monitor takes about 2 minutes to arrive at a smear activity measurement.  In comparison, the time for a scintillation measurement may be hours or days depending on availability laboratory facilities.

The SAM, which is battery operated, may be placed close to an operator for maximum convenience when taking smears.  The operator simply opens a drawer in the SAM, places in the smear paper, waits 2 minutes and reads the measurement.

Measurements are displayed on a large LCD screen on the top of the instrument.  Various settings such as alarm activation thresholds and measurement units can be configured using two push buttons on the top panel.

Tyne can provide an amorphous tritium source of known activity which can be used daily to confirm the calibration of the instrument.  If a particular reading is important, a calibration check can easily be made both before and after the reading.  The calibration-checking source is mounted in a plate which slides into the same drawer used for the smear paper.

The SAM can also be used directly, without smear paper, on flat conducting surfaces such as a stainless steel drum, glovebox, or a laboratory bench to check for tritium on surfaces.  A direct reading, measures not only the removable activity which can be picked up in a smear paper, but also the non-removable near surface contamination which would otherwise not be recorded by the smear.