Frontier Technology Corporation is the world’s expert and leading global supplier of neutron sources and nuclear startup rod assemblies. We manufacture complete startup rod assemblies that include californium-252 (Cf-252) neutron sourcesantimony-beryllium pellets, non-destructive testing (NDT), and all parts of the rod assembly. Rods are produced according to our customer’s specifications and meet and exceed the highest level of safety requirements and standards set by the nuclear industry.

All startup rods are shipped in our Type-A radioactive shipping containers, which are designed for safe and efficient transportation and unloading. Domestic and international shipping are available.

Choose Frontier for Nuclear Startup Rod Assemblies

For decades, we have worked with customers including Westinghouse, Framatome, DOE National Laboratories, and others to provide californium-252 neutron sources, nuclear start up rods, and other critical services. Please contact us to learn more or to request a quote.


Real-World Applications

The Westinghouse team was challenged to meet international standards and urgent timelines of a fuel loading schedule at their Korea-based plant. Learn how Frontier Technologies Corporation helped Westinghouse achieve their goals in this case study.

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Californium-252 as a Startup Neutron Source

While uranium is commonly used as fuel inside a nuclear reactor, it cannot reliably start a nuclear fission reaction on its own. A highly active, stable source of neutron emission, such as californium-252, is needed to bombard uranium oxide fuel rods with neutrons, starting a sustained nuclear reaction.

Startup rods are interspersed with fuel rods within the reactor core to provide the initial reaction that triggers a long chain of nuclear fission reactions from the fuel rods.


Common Applications For Start-Up Rods Include:

  • Axial offset control
  • Emergency shutdowns
  • Reactor and Power control
  • Reactor shutdown
  • Reactor startup

Frequently Asked Questions

What are the advantages of Cf-252?

Cf-252 offers several key advantages that make it useful in a range of industries. As an extremely powerful neutron emitter, it is an ideal startup source for nuclear reactors, which require a large and stable neutron source. Its powerful neutron emission means a small piece of Cr-252 can be used in applications with size limitations such as boreholes and well logging.

Cf-252 sources are portable and temperature-stable, so they can be used in extreme high-temperature environments in the field, not only in labs or other facilities.

Why is Cf-252 expensive?

The main driver of the price for Cf-252 is the fact that there is a limited global supply of it.  Californium-252 does not occur in the natural world and must be synthesized with special high-flux isotope reactors. Because there are only two of these reactors worldwide, and the production process for Cf-252 can take up to two years, the isotope supply remains limited and, therefore, costly.

Production and transportation costs also influence cost.

What are the conversion measurements for 1 microgram (µg) of Cf-252?

  • 1µg = 2.31 x 106 neutrons/second (n/s)
  • 1µg = 0.5mCi
  • 1 µg = 0.02 GBq

Californium-252 Solutions For The Nuclear Industry

Californium-252 (Cf-252) sources are essential to initiate a nuclear fission reaction in nuclear reactor start-up rods. Learn more: