Radium is still used today as a radiation source in some industrial radiography devices to check for flawed metallic parts, similarly to X-ray imaging. When mixed with beryllium, radium acts as a neutron source. Radium-beryllium neutron sources are still sometimes used even today, but other materials such as polonium are now more common: about 1500 polonium-beryllium neutron sources, with an individual activity of , have been used annually in Russia. These RaBeF4-based (α, n) neutron sources have been deprecated despite the high number of neutrons they emit (1.84×106 neutrons per second) in favour of 241Am–Be sources. Today, the isotope 226Ra is mainly used to form 227Ac by neutron irradiation in a nuclear reactor.