I-160 -Sinee Ihave mentioned maximum permissible lune burdens, you Twould lilies lo comraent 9 > are aware that there is official guidance. The maximum permissible iuny burden is established by cquilivrating the exposure from the depozited radioactive acrosol with that ofan accent ‘ne International Commission on Radiological uniform dose cf x-rays. Protection indicates this may be greatly in error, and specifically states x . me . in its publica.tion 9, "In the meantime there is no clear evidence to show . whether, with a given mean absorbed dose, the biological risk associated with a non-homogeneous distribution is greater or less than the risk re. . . - ° 1966). ify (ICRP, They are effectively saying that there is no guidance as to th ce) . sulting from a more diffuse distribution of that dose in the lung.” risk” sar nencthormoygenccous expofture in the ling, hence the maximum permissivle lang burden igs rnaeaningless for plutonium particles, as are the raaximum Qo °o permissible air concentrations which derive from it. So there is a hot particle problem with plutonium in the lung, and the hot particle problem is not understood, and there ig nu guidance as to ti.c risk. I don't think there is any controversy about that. to you from Dr. K. “% Let me quote » . - Morgan's testimony in January ofthis year before ‘ the Joint Committee on Atoraic Energy, U.S. Congress (Morgan, K.Z., 1960). Dr. KZ. Morgan is one of the United States! two members to the rnin Committee of the Internatio:nal Cornmission on R adiologiical Proteclien: he has been a member of the committec longer than anyone: and he is diceclor of Healih Physics Division af Oak Ridge Nationaal Laboratory. . . Lasote: ~ a . “. . eas : : Vhere are rangy Utiegs aboub radiation exposure we do net Wes, . woe me “ Wo ., spy . nes. was, we a tne, ° costspee 7 +. °fsa ve vee et ws : . ij : 6340 Big, > “ 2. pores wo, lay ‘ Shoe —- over one ed,