Types of materials

Type of materials classified according to their rates of absorption from the respiratory tract to body fluids. Type F is defined as deposited materials that are readily absorbed into blood from the respiratory tract (fast absorption). Type M is defined as deposited materials that have intermediate rates of absorption into blood from the respiratory tract (moderate absorption). Type S is defined as deposited materials that are relatively insoluble in the respiratory tract (slow absorption). Type V is defined as deposited materials that, for dosimetric purposes, are assumed to be instantaneously absorbed into blood from the respiratory tract (only certain gases and vapours; very fast absorption). (Publication 130, 2015)

ICRP Glossary entry - May 2019