FIELD: environmental control. SUBSTANCE: procedure includes preparation of aqueous solution of strontium 90 nitride, its injection with granulated polymer of styrenedivynilbenzene impregnated with monoisooctylmethylphosphotic acid, heating of prepared mixture, mixing of heated mixture, separation of strontium 90 in solid phase from nitride solution with extraction of yttrium 90, preparation of counting preparation from it, determination of quantity of yttrium 90 in it and recalculation of determined quantity of yttrium 90 to quantity of strontium 90. EFFECT: increased reliability of determination of strontium 90, enhanced safety and reduced time of realization of procedure.
