A compihation of information concerning beryllium oxide hydrolysis problems is presented. A summary of system equilibrium and corrosion kinetics is given. An assessment was made of consistency and engineering utility of experimental deposition tests. It was conchuded that the test device used is satisfactory for screening purposes and for ihlustrating general effects of temperature heveh and moisture contents. Fair correlation of test results was obtained by present methods, but both the uncertainties and limitations of test information precluded formuhation of specific design equations. (auth)