Various embodiments are directed to methods and apparatuses for determining a remaining lifespan value for a filter component configured for use in a respiratory protective device. In various embodiments, the method comprises determining a net volatility associated with a dispersing element of a filter component of a respiratory protective device; and based at least in part on the net volatility associated with the dispersing element, determining a remaining lifespan value for the filter component; wherein the net volatility associated with the dispersing element is determined based at least in part on one or more approximation algorithms defined according to one or more operational characteristics associated with the respiratory protective device. In various embodiments, the net volatility associated with the dispersing element is determined based on a plurality of approximation algorithms defined according to a respective plurality of operational characteristics associated with the respiratory protective device.