Radon Calibration Facilities

Since 1981 the Airborne Radionuclides Group of the HPA has operated a radon exposure facility for calibration and research purposes. Radon gas concentrations are measured using instruments with calibrations traceable to the UK National Physical Laboratory and PTB, Germany. The primary facility is a 43 m³ walk-in chamber accessed by an airlock. Radon gas is maintained at a level in this chamber that is high enough to allow exposures to be completed in a relatively short period of a few days whilst allowing staff reasonable access to carry out work.

The chamber is suitable for a wide variety of radon detectors and instruments. HPA staff have experience with most types in current use. The chamber has also been used to test other types of equipment, such as determining the radon response of actinide in air contamination monitors and etched-track neutron dosemeters.

Whilst most calibrations will be carried out by HPA staff, it is also possible for customers to hire the chamber by the day in order to carry out work or calibrate instruments. HPA staff monitor, control and report the conditions in the radon chamber.

The HPA also carries out an annual intercomparison of passive radon detectors using the radon chamber, which is open to anyone wishing to participate.

A secondary facility, the Fast Radon Exposure Device (FRED) is also available. This facility has a very high radon concentration suitable for carrying out radon exposures in a short time interval or for giving high exposures to detectors for such purposes as determining linearity of response. This facility is much smaller than the radon chamber and can only be used for small numbers of detectors. It is not suitable for most active instruments.

For all enquiries please contact:

Chris Howarth (chris.howarth@hpa.org.uk) or Richard Algar (richard.algar@hpa.org.uk)

Radon Dosimetry Team

Dosimetry Services Department
Health Protection Agency
Chilton, Didcot
Oxon OX11 0RQ
United Kingdom

Details of calibration facilities

HPA radon chamber

Typical radon concentration: 2,000-8,000 Bq m^-3
Volume: 43 m³
Monitored continuously: radon gas, temperature, humidity, barometric pressure
Additional variables available for monitoring: decay products, working level, equilibrium factor, ambient aerosol, unattached fraction
Controllable parameters: radon gas concentration, equilibrium factor (F), aerosol concentration
Uncertainties (95% CL): radon gas 10%, decay products, working level, equilibrium factor 20%

Fast Radon Exposure Device (FRED)

Typical radon concentration: 40-70 kBq m^-3
Volume: 0.2 m³
Monitored continuously: radon gas
Uncertainties (95% CL): radon gas 20%

Prices for standard services offered by the Airborne Radionuclides Team

All prices are with effect from April 2012 and are exclusive of VAT.

RC = Radon chamber, FRED = Fast Radon Exposure Device

Passive detector calibrations

Type of exposure	Facility	Cost £
< 2,000 etched track detectors	RC	670
2,000-10,000 etched track detectors	RC	790
Up to 50 charcoal detectors	RC	670
Up to 100 electret detectors	RC	670
Monitoring of F, each day over 7 days	RC	74
Up to 80 etched track detectors	FRED	330
Further multiples of 80 detectors	FRED	264

Instrument calibrations

Type of instrument	Facility	Cost £
Radon gas monitor	RC	660
Each additional instrument	RC	198
Radon decay product meter	RC	660
Each additional instrument	RC	198
Lucas cell system (Pylon, RDA or similar) plus up to 5 passive cells or scintillation trays	RC	660
Lucas cell system (Pylon, RDA or similar) plus 1 flow through or diffusion cell	RC	660
Each extra instrument with cells as above	RC	198
Each additional passive cell or scintillation tray	RC	67
Each extra flow through or diffusion cell	RC	198

Hire of radon chamber

First day	£462
Each additional day	£330

 

Use of FRED by customer

 

Per day	£296

 

Notes

These prices are for guidance only: complex exposure schemes, novel equipment or other factors may result in raised costs. Please provide as much detail as possible when enquiring about calibrations.

Please note that there are periods when the radon chamber will be very busy and there may be a delay of weeks before calibration can be carried out.

Instruments sent for calibration must include all necessary accessories such as power leads, connecting tubing, or desiccant. Failure to provide these could result in delays as the required equipment may not be available.

Last reviewed: 8 May 2012