Tabte I. PARAMETER VALUES Task Group Lung Model Parameter Values values of f. and T, [3] are Typical values of Ds D,» and D, and recommended FRACTION OF INHALED PARTICLES DEPOSITED (a) IN THE RESPIRATORY SYSTFM VERSUS PARTICLE DIAMETER Particle Size AMAD Micrometers given in Table 1. Fraction of Inhaled Quantity Retained Nasopharyngeal Tracheotronchial Pulmonary Region, D3 Region, D, Region, De 0.05 0.1 0.3 0.5 1.0 2.0 5.0 0.001 0.008 0.063 0.13 0.29 0.50 0.77 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.59 0.50 0.36 0.31 0.23 0.17 0.11 classificaTable 3 of Ref. [1] gives the pulmonary clearance , For suitable values of fis f5> Th Ty tion (D,W,Y¥) of inorganic compounds. M_, and A EEF(RBE)n), see Refs. [3,4,5]. n GENERAL TREATMENT by clearance The subcompartments of the respiratory tract are identified pathways (K = a,b,...h). Equations for calculating burden, dose, and dose commitment for a given subcompartment are as follows: Burden = a dQ, CLEARANCE PARAMETER vatues ©) =e = = = Compartment k NP TB P L a a = b dt D qT, fy Translocation Class W b b T.. f. Ty. SQ. + MQ = £,D Q/8. if Q, is constant Y fy b 0.01 0.01 0.50 0.01 0.10 0.01 0.40 0.99 c 0.01 0.95 0.01 0.50 0.01 0.01 d 0.20 6.05 0.20 0.50 0.20 0.99 e 0.50 0.80 50 1 50 50 Q.15 0,40 0.40 0.05 500 0.05 i 0.50 1.00 50 1.00 1000 0.90 £ gz h = EO a So n.a. Nea. 0.50 0.50 Ta. n.a. 0.20 0.40 0.90 1 500 500 (a) Estimated from data of Task Group on Lung Dynamics. (9) 0.01 0.40 0.40 0.15 Qe = FPn@y/SE8 + AY? Q, = (EDI /Ay) (exp Gay t)) (1) Dose = Dd t De = RED aly (L-exp(-A, t) dt Dd. = (REDQh) (. 1-exp(-A,t) } ik (b) As amended by ICRP Publication 19 (2). D.W.Y. = Days, Weeks, Years loc, = Clearance pathway (See Figure 1) ry = Biological half-time (days) for pathway k fi. = Fraction cleared by pathway k 694 695 (2)