Flange gaskets for piping joints and / or valves? Seat or stem gaskets for valves (and what type)?
'Gaskets' compatible to your liquid and temperature (PTFE,FKM) will in a fire melt or burn at a certain point (depending on fire development).
If the normal inforced are not compatible, there could be that neiter certified firesafe gaskets or firesafe tested /certified valves exists in the market suitable
for your process.
Remember that firesafe tests for valves actually involves
a complicated and costly test where you actually test with fire and burn out the valves, and that you afterwards have to test with pressure against minimum leakage requirements.
You therefore have a difference between a firesafe certified tested component, and a certified designed component. The design is similar to other components already tested, but that particular type, size or pressure class (whatever) is not tested istself.
If you do not find components that qualify in either aspect all fire-resisting estimates for a product will then at best be a non-qualified guesstimate, with at best a doubtful juridical backing, should the worst happen.
In this case my advice is to look at the total fire and accident protection for pipeline with sourronding buildings, areas etc with emergency shut-downs, relief, fire- and explosion preventing devices.