Size distribution of aerosols dispersed during plasma cutting of MOX fuel fabrication equipment

Kitamura, Akihiro   ; Nakamichi, Shinya  ; Kashiro, Kashio

Plasma arc cutting is considered to be one of the effective methods to size reduce facility components. This method produces an electrical arc to cut the metal equipment, and during the cutting, a molten metal is ejected in the form of aerosol, which is blown away from the torch and has a potential to spread all over the environment. In order to confirm the safety use of plasma arc cutting for dismantling activity in plutonium fuel fabricating facility, we have performed experiments to find aerosol size distribution and to confirm effectiveness of HEPA filter during the cutting. Results showed that the activity median aerosol diameter was around 6 micrometers, with a geometric standard deviation of 1.9. Also, radiological survey was conducted on the back surface of HEPA filter and confirmed that the penetration of radioactive aerosol was under detection limit.