Defined charge distribution for SMPS measurements

The Kr-85 Neutralizer is a bipolar neutralizer that generates positive and negative ions through ionization with the emitted β radiation. Suppose these ions are brought together with an aerosol; a defined equilibrium charge distribution is established, as is necessary for measuring systems, such as scanning mobility particle sizers (e.g., Palas U-SMPS system). This neutralizer is available in two versions with different activities, 75 MBq, and 370 MBq.

Compared to unipolar neutralization, bipolar neutralization has a significant advantage: regardless of the initial state of charge of the particles, a reproducible equilibrium charge distribution is always established. Bipolar neutralization is mandatory for traceable calibration of a condensation particle counter (e.g., ISO / CD 27891).

As the Kr-85 neutralizer is an enclosed radioactive source, additional requirements for documentation and handling regarding radiation protection should be considered. Should you have any questions, we would gladly support and advise you. Regarding the dangers of Kr-85, the following can be said: "Krypton 85 (Kr-85) is a radioactive noble gas. When released, it is practically not absorbed by the body; inhaled Kr-85 is exhaled again. [...] Kr-85 is a radioactive substance with a relatively low radiotoxicity. When Kr-85 is released, it is [generally] sufficient to provide ventilation of the working area for a short while." [KomNet scientific database dialog 6753]

Operation principle

Your special advantages

  • Reliable method for defined charge neutralization
  • Long lifetime
  • Low maintenance
  • Low operation costs

Individual solutions for various industries

  • Neutralization for SMPS systems
  • Neutralization for filter test systems
  • Neutralization for diverse measuring tasks and to avoid particle losses due to electrostatic deposition
Do you have any further questions?
Please do not hesitate to contact us.
Technical features

In detail

Volume flow
Up to 5 l/min
Stainless steel
Aerosol outlet connection
Øinside= 4 mm, Øoutside = 6.5 mm
Activity of the radiator
370 MBq
Type of radiation
Operation principle
Ionisation of air molecules by radioactive radiation
Half-life period of the radiator
10.8 years
Aerosol inlet connection
Øinside= 4 mm, Øoutside = 6.5 mm
38.3 • 220 mm (Ø • L)
500 g

More information about Kr-85-370

Brief Description

Brief product description in two-pages as PDF

Product Description

Detailed product description as PDF

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(Art-No: 480keine) - Kr-85-370

(Art-No: 1281keine) - Protective lead enclosure


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