s PFEECT~ 0 HO percent of the ose cad been recered. dose rate had fallen cess cha fo is initial value fered from the laboratory, Thos os.) constant le perce: be otose rate ais rate or ON ZING ADTATION ne Gose at fhe center of the body is approxi- at ngery > f OO oercent tigher than would result “oom a vive air dose with narrow beam geom- ou ry Vigure 1. allustrates the depth dose eve feom: an experimental situation using fm - oe wis ore eee ee I EVACUATION AT 51 HR - ; . BO}. | a | k I ~ 100 k— -—- x 3 i. -= ‘ Ww o Oo . . x -- —--—+ ke a a 2 KF sop——-. r . 2 4 HR 2 L__|a, - 0 Ln wee en 40 Med “Tah Roi. fae deviation commenecenone 1.23 om t f ue tion is delivered from i pebutar source the usin diffuse 440) with depth on tessue that resulting: from stlom held the app ueable decrease of tf, chose - ress prodouaere ofa oa ty ateeal oe posture I A-ray beam becuuse fillet) feom inverse square In in effect neutinitee | a 40 50 eR aceon funetion of time after spherteaily orrented Co? sources with a phan- out radiation is ~ yar i@nificantis different from: usual laboratory sour es “ince fallout rad.a il RM OUR yamond dage ferences the geometry oot the exposure o faci narrow beam geometis tao t — falieutun Rongelap «tall, Geometry of the Exposure In addition te the stose rate and enersy such | Fort) Sane peter, rom laced at thetr center, compared with a onventional bilateral depth dose curve ob- ‘uined with a single source «+). In the latter ase, the air dese is usually measured at the point subsequently occupied by the center of ‘he proxunal surface of the patient or animal ath respeet to the source. For the tield case, (i surfaces ure “proximal,” in the sense that ne air tose measured anywhere in the space ~ubsequenthy oecupled by the individual is the wine Tt is this arr dose which ts measured ebb onstrument: it does not bear the same