Alpha Emission Standards
DESCRIPTION
The radioactive substance in thin layer on the Pt foil is squeezed to the duraluminium casing with dimensions. 25 x 5 mm (diameter x height). The casing has front window with diameter of 6 mm. The active area must be carefully protected against moisture, dust and abrasion.
APPLICATION
They are widely used as control sources in comparative measurements, for energy and efficiency calibration of alpha-spectrometers, determination of efficiency of window and windowless counters of α particles.
MEASUREMENT
Flux of α particles to spatial angle 2π sr is determined by 2π proportional counter. Activity is calculated from flux using correction on back scattering, spatial angle and self-absorption.
Standards of Photon Flux
DESCRIPTION
Standards of X and g photon flux type EFF and EFX are the point sources with minimum self-absorption emitting homogeneously to angle near 4π sr. The activity is deposited between two welded polyethylene foils with square weight 3,6 ± 0,3 mg.cm-2. The foils are located in the metal ring with outer diameter 40 mm. The active material is located in the center of the foil.
APPLICATION
Standards EFF and EFX are designed for energy and efficiency calibration of counters and spectrometers of X and γ photons. The activity of the standard gives the source strength approximately ~104 s-1
MEASUREMENT
The source strength of the EFX standard is determined by means of a suitable 4π counter. For the standards EFF (emitting photons γ) source emission is calculated from the activity and the known photon yields.
Standard Sources for Gamma Spectrometry
DESCRIPTION
Standards of γ photon flux EFS are the point sources with minimum self-absorption emitting homogeneously to angle near 4π sr. The activity is deposited between two welded polyethylene foils with thickness less than 0,2 mm. Foils are mounted in the metal ring with outer diameter 35 mm. The active material is located in the center of the foil.
APPLICATION
The standards EFS are designed for energy and efficiency calibration of gamma spectrometers with Ge(Li) and HPGe detectors. Used radionuclides cover energy range 100 keV - 2 MeV.
MEASUREMENT
The activity of the standard is calculated from the mass and specific activity of the standard solution. The specific activity is determined by absolute measurement.
Gamma and X Reference Sources
DESCRIPTION
A weighed amount of the standard solution is dropped on the disc of filter paper in the polymethylmetacrylate capsule. The capsule is sealed up, when dried. The capsule and the reflector layer of common NaI(Tl) scintillators provide a sufficient filtering of β radiation of relevant radionuclide. For 144Ce this filtration is not sufficient and for the types EG 1 and EG 3 layer of minimum 3,2 mm Al between the standard and the detector is necessary.
APPLICATION
Energy and efficiency calibration of scintillation spectrometers and counters of γ and X radiation. They can serve as reference sources for relative measurements. Their activity is chosen so that:
- standard EG 1 in closed geometry with the NaI(Tl) 38 x 25 mm
- standard EG 2 inserted to the well of NaI(TI) 45 x 50 mm
- standard EG 3 located 10 cm from the forehead of NaI(Tl) 38 x 25 mm
Gives approx. 1700 counts per second for energy higher than 30 keV.
MEASUREMENT
The activity of individual standards is calculated from the mass of the standard solution and is checked by relative measurements of γ photon flux. The specific activity is determined by absolute measurement using 4π β-γ, 4π α-γ or 4π X-γ coincidence method or 4π proportional counter.
Standards in Marinelli Beakers
DESCRIPTION
Marinelli beakers are filled with silicone rubber containing uniformly distributed radionuclide or mixture of radionuclides. Default density of the active volume is 0,98 g.cm-3 and mean atomic number approaches water. The standards are available in 3 types of polypropylene beakers with default volumes 450, 500 and 1000 ml. Other volumes, nuclides, activities or beakers are available on request. Custom geometry can be filled with no extra charge.
APPLICATION
Energy and efficiency calibration of gamma spectrometers.
MEASUREMENTS
The standards are prepared from the standard solutions ER(EB) whose activity is determined by absolute method. The final sources are checked by measurement on gamma spectrometer with HPGe detector. Combined standard uncertainty of activity is approx. 2 %.
Multi-Gamma Mixture
DESCRIPTION
Mixture of 10 isotopes (241 Am, 139 Cd, 57 Ce, 60 Co, 137 Cs, 113 Sn, 85 Sr, 88 Y, 203 Hg) developed especially for calibration of gamma measuring equipment. It covers the gamma energy range of 59,540– 1836,03 keV with 12 energy peaks. Combined standard uncertainty of activity is below approximately %3.
APPLICATION
Energy and efficiency calibration of gamma spectrometers
PRODUCT TYPES
Our multi-gamma mixture can be used in a wide range of forms including the most popular: liquid solutions (ER-mix) and a silicon resin (CBSS2). Without Hg-203, it can also be produced as a planar source (EM/EZ), filter or a sample of contaminated steel (ES).
Standard for Contamination Monitoring
DESCRIPTION
Standard radionuclide solution is deposited on a disc metal base in approx. 50 dots/cm2. Evaporated solution is overlayed with thermally cured layer of protective laquer and aluminum layer with square weight approx. 20 µg/cm2 deposited in vacuum. Square weight of protective layer is less than 0,1 mg/cm2. The active layer must be protected against dust, touch and corrosive atmosphere.
APPLICATION
Efficiency calibration in measurements of various radionuclides in thin layer particularly for checking of relative measurements in surface, water, air and personnel contamination with α and β emitting radionuclides. Likewise for checking of stability of contamination monitors. For measurements of contamination can be used also standards EZ with larger active area.
MEASUREMENT
The activity is calculated from mass and specific activity of standard solution, traceable to primary activity standard. Surface emission is measured with windowless proportional counter with uncertainty < 1 %. Both values are specified in associated documentation.
Ra-226 Standard - Solution
DESCRIPTION
Aqueous solution of the appropriate quantity of 226 Ra. Chemical composition of the solution: 1 g BaCl2 /l and 10g HCl/l. EB 00 is the aqueous solution of 1 g BaCl2 /l and 10 g HCl/l with very low and determined mass fraction of 226 Ra.
APPLICATION
The standards are designed for efficiency calibration of activity (mass) determination of 226 Rn. Standard solutions are used either in the form of sealed ampoules for calibration or weighed part of the solution can be added to the analyzed sample as so called internal standard. After dilution by EB 00 solution is possible to prepare working standards with activities similar to measured samples. For emanometric determination of 226Ra 222 Ra in water, air and so on it is possible to transfer them to a washing bottle from which radon is expelled by a stream of gas.
MEASUREMENT
Standard solutions are prepared by dissolving of Ra content of standard ES activity of which was determined by comparison of gamma photon flux of the standard with the flux of IIR primary radium standards. Comparison is carried out by means of the 4π -γ ionization chamber of IIR.
Ra-226 Standard - Solid
DESCRIPTION
A mixture of RaSO4 and BaSO4 is encapsulated in a cylindrical cell which is soldered, put in a tube or needle with length 13,5 - 25,5 mm and diameter 1,65 - 2,65 mm and soldered again. Both the cell and the outer capsule are made of alloy of 90 % Pt and 10 % Ir. The total wall thickness is 0.5 + 0.05 mm which is sufficient to absorb all alpha and beta radiation.
APPLICATION
The standards are designed for calibration of dosimetric instruments, efficiency calibration in activity measurements of Ra and other radionuclides. The calibration of dosimetric instruments is based on the knowledge that 1 g of 226 Ra with a 0,5 mm Pt filter has an exposure rate of 59,12 x 10-9 A.kg-1.
MEASUREMENT
Mass of 226 Ra is determined by comparison with IIR primary radium standards by means of 4π -γ ionization chamber. Radiation of primary standards is filtered with 0,5 mm Pt.
Er- Universal Radioctive Solutions
DESCRIPTION
Approximately 1 or 5 g of the radioactive solution is sealed in a glass ampoule. Review of types and their parameters is in the table 1.
APPLICATION
The standards are designed for efficiency calibration of all kinds of detectors, type ER 2 is especially suitable for the calibration of proportional, scintillation and GM counters, types ER 3 and ER X for ionization chambers. Standard solutions are used either directly or after dilution for preparation of working standards. Application for internal standards is also possible.
MEASUREMENT
The ER 2 and ER 25 standards are directly prepared from a standard solution, the specific activity of which was determined by absolute measurement using the 4π ( α , ß , X, e) - γ coincidence method or by a 4π proportional counter. The specific activity of the ER 3 and ER X standards is calculated from the dilution ratio and the specific activity of ER 2 standard solution.
AVAILABILITY OF NUCLIDES
Nuclides are divided into three categories. No Availability class means they are usually in stock. Class D represents nuclides available on request, the delivery time is usually 8+ weeks. Nuclides in class F will be ordered and produced twice a year, usually in April and October, so please make sure to plan their use ahead.
Esi - I125 Simulating Radioactivity Standart
DESCRIPTION
1 ml of polymerised mixture of epoxy resin containing 241Am and 129I in the plastic test tube with dimensions 12 x 73 mm (diameter x length). Activities of 241Am and 129I in are in such a ratio that resulting spectrum γ on a well type NaI(Tl) detector corresponds as much as possible with 125I spectrum. Test tube is closed by plastic stopper.
APPLICATION
The standards are designed for the calibration and checking of RIA gamma counters, especially for the measuring of kits with 125I
MEASUREMENT
The effective activity is determined by the comparison measurement with 125I working standards using the gamma spectrometer with a well type NaI(Tl) detector 50 x 50. Nominal activity is 1500 Bq of 125I
Emei – Methyl Iodide Labelled With I131
DESCRIPTION
Set of 10 pieces of 5 ml glass ampoules containing 30 kBq , 131I each, absorbed in 0,1 g sorbent for gas chromatography. After opening ampoule, methyl iodide can be released by heating on 200 - 250 in stream of carrier gas (air, Nitrogen). Content of I in ampoule is 2 mg (nominal values).
APPLICATION
For checking of gas monitors in nuclear facilities, especially in nuclear power plants.
MEASUREMENTS
Activity is determined by gamma spectrometry with HPGe detector.
NOTE
Combined standard uncertainty is (P = 68,3 %) nominally 1,5 %.
Enm – Standarts For Nuclear Medicine
DESCRIPTION
Standards in 10 ml penicillin vials in form of polyacrylamide gel, active volume is 5 ml. In case of breaking the vial , polyacrylamide gel prevents larger contamination, which the radioactive solution would not.
APPLICATION
The standards are used for calibration and checking of measuring devices in nuclear medicine, e.g. activity calibrators.
MEASUREMENT
The activity is determined by measurement in 4π ionization chamber, which is the part of national
Ed – Standarts For Nuclear Medicine – Pen Point Marker
DESCRIPTION
Dried weighed part of standard solution of 57Co is closed in a cylindrical plastic capsule with dimensions 11 x 9 mm (diameter x length). The source is installed on the top of the telescopic holder. Nominal activity is 5 MBq.
APPLICATION
The source is used mainly as a marker in nuclear medicine.
MEASUREMENT
The activity is calculated from the mass of the standard solution.
Evp – Standarts Of Rare Gases
DESCRIPTION
Standards of radioactive rare gases 41Ar, 85Kr, 133Xe are designed for calibration and checking of monitors of
nuclear facilities outlets, especially those of nuclear power plants. Known activity of radioactive gas is closed in the steel pressure bottle in mixture with air under pressure up to 100 bar. Declared quantity is volume activity at normal conditions. Technology of production is described in documents 911-MP-C001-07, 911-MP-C002-07 and 911-MP-C003-07.
APPLICATION
Radioactive gas is blown off to the monitor systems of nuclear facilities.
MEASUREMENT
Activity of 41Ar is determined by gamma spectrometry with HPGe detector, activities of 85Kr and 133Xe by measurement with calibrated ionization chamber.
NOTE:
Normal conditions are p = 101,3 kPa and t= 0
Rf - Rn222 Flow Through Source
DESCRIPTION
Accurate and long term stable sources of defined activity of 222 Rn in gas phase.
Radon is released from thin layer of a plastic foil with emanation power approaching
The source is constructed as a stainless steel cylindrical case supplied on the ends with the two ball valves and the two aerosol filters connected on the output aperture of the valves. All parts are made from stainless steel or Teflon. The sources are produced in activity range 20, 100, 200, 500, 1000 a 2000 kBq of 222Rn with commercial label RF 20, RF 100, .... RF 2000.
APPLICATION
The sources are designed for laboratory and field conditions. The main application is calibration of devices and detectors for activity measurements of 222Rn and 226Ra in environmental research. The user can apply the source in batch or flow through mode.
MEASUREMENT
The activity of 226Rn is determined by comparison with IIR standards, the emanation power by gamma spectrometry on a HPGe detector.
Es - Contamined Steel Samples With Co60 AND Cs137
DESCRIPTION
Cylinder shape standards type ESCO and ESCS consist of outer case with inserted discs with activity of 60Co or 137Cs. Activity is deposited in points in the net 5 x 5 mm. Discs putting together originate a cylinder with approximately homogeneously deposited activity. Disc and case are made from polished stainless steel. Standard dimension of cylinder is 35 x 15 mm, standard dimension of one disc is 34 x 0,8 mm (diameter x thickness). Other dimensions are made according to requirements of customer.
APPLICATION
Standards are designed for efficiency calibration of gamma spectrometers used for checking 137Cs and 60Co activity in steel. These radionuclides can occur in scrap iron as a result of liquidation of medical or industrial sources. According to customer requirements is possible to prepare standards with other radionuclides or with mixture of radionuclides.
MEASUREMENT
Activity of the standard is calculated from the mass and specific activity of the standard solution. The specific activity is determined by suitable absolute method. Produced sources are checked by comparison with IIR by standards gamma spectrometry with HPGe detector.
Si – Dosimetric Si-1 And Si-2
DESCRIPTION
The diodes Si-1 and Si-2 are long base silicon diodes (LBSD) developed for measurement of kerma from heavy particles, particularly fast neutrons. The main physical effect, which is used for kerma measurement, is the change of t as the minor charge carriers lifetime in silicon after irradiation due to radiation damage in the crystal lattice. Because of the difficulties in lifetime measurement, the forward bias voltage drop on the diode is measured. The change of this voltage ʌU i.e. the difference between the voltage U after irradiation and the initial voltage U is taken as a measure of the radiation damage and is approximately linear function of kerma K from fast neutrons. Both types has very low sensitivity for gamma irradiation and so they can be used in mixed gamma -neutron fields. Diodes Si-1 and Si-2 differs in technical specifications, type Si-2 is more sensitive and therefore useful in personal dosimetry (see table).
APPLICATION
The main utilizations are: measurement of kerma from fast neutrons for purposes of personal and accidental dosimetry, military dosimetry, mapping of neutron beams.
MEASUREMENT
The constant current pulse (25 mA, 40 ms) is used for measurement of forward voltage. For this purpose CMI IIR is capable to supply special measuring device. The dependence of the voltage change of Si-2 diode on the value of the neutron tissue kerma K for neutrons from unshielded 252Cf.
