Our instruments have several names:
radon counters, portable radon detectors, emanometers, sniffers, lucas cells, alpha scintillometers

Technical specification sheets and pictures of our instruments provided on request.

Portable Radon Detector

Water Degassing System

Lucas Cells

The Lucas-cell counting system like ours is (to our knowledge) the only method with sufficiant sensitivity for lake water surveys. Lucas cells provide the basis of EPA Method 903.1 for radium in water.

Lucas cells can determine thoron (radon-220) and hence radon/thoron ratios. In just a few minutes, our instrument counts 75% of the thoron atoms in the sample, hence giving us an accurate determination of the ratio.
One operator suggested using a gamma-ray spectrometer at the sample site to identify thoron. Given the short (55-second) half-life, it is impossible that enough thoron would migrate into the soil gas to give a gamma signal recognizably above background from gamma emitting daughters of thoron locked in mineral grains.
Several other radon systems have been marketed and used for uranium exploration. I have listed them below for the sake of completeness, but I'm not sure if any of them have the sensitivity for radon/thoron ratios or lake water surveys:
various alpha track (etched track or track etch) detectors using sensitized cellulose nitrate film or filmstrips, alphaNuclear, Electret (EIC), rad elec, e-perm, ionization chambers, granular activated charcoal or carbon filters (canisters), thermoluminescent dosimeters (TLD chips), alpha spectrometers. The electroscope was one of the earliest systems for detecting radon and was earlier than the geiger counter.

We also provide solid state alpha spectrometers and working level meters for health and safety applications.
  • We measure: radon - radium - thoron - radon daughters - alpha radiation.
  • The Lucas cell is recognized as the most sensitive and reliable method for these elements.
  • Intrinsically safe functions.
  • Sensitive to geochemical trace levels necessary for radon in lake water and for radon-thoron isotope ratios.
  • immune to beta and gamma radiation.
  • one monitor works with a number of (less expensive) detectors.
  • Our instruments are used around the world in exploration for uranium, oil & gas, groundwater and hydrothermal, and in environmental protection, health physics, earthquake prediction, and evaluation of hydrocarbon and NAPL contamination etc.
  • Same instruments used for radon and radium in soil, sediment, plant parts, rocks, water, soil gas, air, snow, food, and for radon and thoron daughters in air.
  • Winter and summer, from the Sahara Desert to the Canadian Shield, our instruments have faced up to severe field conditions.
  • In the radon business since 1968, our instruments are updated regularly with the most recent major re-design in 2015. Modern, low-power, field-rugged electronics. Some earlier versions still working after 40 years.
  • Continuous real-time monitoring and data recording.
  • RS232 port/pc software.
  • User programmable measurement intervals, sample and count periods and alarm level settings.
  • Can work in a tent without electricity or be carried from point to point in the field.
  • 50 readings per day. Results available immediately.
  • Portable. Rechargeable battery pack good for a long day in the field and recharges in a few hours.
  • Can be operated by junior personnel if carefully supervised.
  • EPA and CE Mark compliant.
  • Click here (www.finderschoice.com/rn) for more details of our radon instruments, and for other instruments, components and accessories we provide.
  • Technical specification sheets and pictures of our instruments provided on request.
  • Multilingual consulting and training (if required).
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