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.
- Measuring radon/thoron concentrations in indoor or outdoor air
- Measuring in situ radon and thoron emanation from rocks and soils
- Quantifying radon concentrations in, or exhalation rates from, gaseous, liquid, solid and mixed phase samples
Please refer to the laboratory 'fact sheet' for more 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 gamma detector is used to measure rates of radon emanation from solid samples (sands, soils, crushed ores etc; sample grain size not exceeding 1-5mm). The difference in gamma 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, or from a pressurised source. Exposed traps need to be shipped directly back to ANSTO for analysis on our Radon Rig.
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 in buildings, tunnels and caves, 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 weeks, to years. With a lower limit of detection of 30-40 mBq m-3, these detectors are suitable for monitoring atmospheric radon concentrations with a high precision down to very low concentrations (e.g marine air).
|Summary of the Radon Analytical Laboratory Facilities|
|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|
|Solid / liquid / gas||20 per day||Instrumental BG <0.5 cpm; LLD depends on volume sampled|
|Gamma spectrometer||Emanation (sample)||Solid||30 days per analysis*||0.5 kg sample, grainsize <5mm.|
|Rn Emanometer|| Emanation |
|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.
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
Phone: +61 2 9717 3694