FIC in Simple Pyrolysis Reactions

[Prometeo-ianic]

Hi all

I have seen cases where, when using a global reaction such as:

&SPEC ID='SFPE POLYURETHANE_GM27_fuel', FORMULA='C1.0H1.7O0.3N0.08'/

&REAC ID='SFPE_POLYURETHANE_GM27',
FYI='SFPE Handbook, 5th Edition, Tables A.38 and A.39',
FUEL='SFPE_POLYURETHANE_GM27_fuel',
CO_YIELD=0.042,
SOOT_YIELD=0.198,
HEAT_OF_COMBUSTION=1.64E+4,
RADIATIVE_FRACTION=0.537/

the FIC quantity remains essentially zero during the simulation.

In other cases, when using formaldehyde as the fuel formula, I observed an increase in these tenability-related parameters.

From a physical point of view, I would expect polyurethane combustion products to potentially generate some degree of irritation and therefore contribute to FIC/FEC-related effects.
What would be a reasonable workaround or modelling strategy to account for irritant species and their contribution to FIC/FEC?

Thank you very much for your help.