ANSTO's research capabilities, led by the OPAL nuclear research reactor and associated instruments provide access to users investigating areas as diverse as materials, life sciences, climate change and mining/engineering.
Radon Analytical Laboratory: Commercial and Research Capabilities
The radon analytical laboratory specialises in the monitoring and analysis of natural radioactivity resulting from radon (222Rn), thoron (220Rn), radium (226Ra) and their progeny.
Specifically:
- Measuring radon/thoron concentrations in indoor or outdoor air,
- Measuring in situ radon and thoron emanation from rocks and soils, and
- Quantifying radon concentrations in, or exhalation rates from, gaseous, liquid, solid and mixed phase samples.
Please refer to the laboratory “Fact Sheet” for more detailed information.
Laboratory-based facilities
“Radon Rig”: employs a de-emanation technique, whereby radon released from a sample is captured by activated charcoal for subsequent analysis by alpha-decay counting. The rig is used for measuring very low radon concentrations in, and radon exhalation from, solid, liquid or gaseous samples under normal pressures.
Liquid Scintillation Counter: A Tri-Carb 3100TR is available to quantify a broad range of radon concentrations in air and clear water samples for environmental or industrial purposes.
Gamma spectrometer: A germanium crystal y-detector is used to measure rates of radon emanation from solid samples (sands, soils, crushed ores etc; sample grainsize not exceeding 1-5mm). The difference in y-activity of radon progeny in the sample pore space is determined over a 30-day equilibration period.
Facilities for in situ monitoring
Single-trap Radon Sampler: stainless steel traps, containing 115g of activated charcoal, can be exposed in situ with this portable sampler, either using the inbuilt pump, of from a pressurised source. Exposed traps need to be shipped directly back to ANSTO for analysis.
Radon emanometer: employs the flow-through accumulator method to simultaneously measure the radon and thoron flux densities, in situ, from soil or rock surfaces over a 30 minute period.
AlphaGUARD: Five portable Saphymo GmbH Alpha Guard radon monitors are available for the continuous, hourly measurement of moderate to high concentrations of radon in air (2 – 2 000 000 Bq m-³). Although designed for indoor use (buildings, tunnels, caves etc), they may also be placed inside ventilated enclosures for outdoor monitoring.
Dual flow loop, two-filter radon detectors: Two models (700 L and 1500 L) of semi-portable radon detectors are available for continuous, outdoor, hourly monitoring of ambient radon in air for periods of several weeks, to several years. With a lower limit of detection of 30-40 mBq m-3, these detectors are suitable for monitoring even quite pristine air.
| Summary of the Radon Analytical Laboratory Facilities |
| Instrument | Measurement | Medium | Analysis rate | Comments |
| Liquid Scintillation | Concentration (sample) | Liquid/gas | 30 min per run | 20 mL samples; LLD 200 Bq m-3; up to 300 samples per run. |
| Single-trap sampler | Concentration (in situ) | Gas | 20 per day | 1 L min-1 sampling; 60 traps available; analysis performed on radon rig |
| AlphaGuard | Concentration (in situ) | Gas | 10-60 min per measurement | LLD 2 Bq m-3 |
| 700/1500L Rn detectors | Concentration (in situ) | Gas | Hourly measurements | LLD 0.03-0.04 Bq m-3 |
| Radon Rig | Concentration Emanation (sample) | Solid / liquid / gas | 20 per day | Instrumental BG <0.5 cpm; LLD depends on volume sampled |
| y- spectrometer | Emanation (sample) | Solid | 30 days per analysis* | 0.5 kg sample, grainsize <5mm. |
| Rn Emanometer | Emanation (in situ) | Solid | 30 min per measurement | LLD = 4 mBq m-2 s-1; typically 10% measurement error. |
* Numerous samples can be counted sequentially and then left for their 30-day equilibration time.
Contact Details
For general enquiries, or more detailed information regarding radon / thoron measurement capabilities, or research and commercial applications, please contact:
Dr Alastair G. Williams
Leader, Atmospheric Mixing and Pollution Transport group
ANSTO Institute for Environmental Research
Australian Nuclear Science & Technology Organisation
Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
T +61 2 9717 3694
E Alastair.Williams@ansto.gov.au