Judges are required to follow the rules of evidence. The judge is unlikely to exclude someone for not knowing the difference between a fire alarm system and a life safety notification. Most judges would see that as unimportant and probably irrelevant to the case. On the other hand, a judge would properly exclude a fire investigator who did not know the difference between power and heat flux.

Yes, I know that many IAAI-CFIs would flunk a simple quiz. But because they hold themselves out as experts, they are implicitly stating that they meet NFPA 1033, and often they will explicitly state on the record that they meet 1033's requirements. When they say that, the judge has every right to compare the qualifications to the requirements that these folks say they meet.

The low-temperature ignition case you are referring to is Truck Insurance Exchange v Magnetek from Colorado. The judge was upheld for excluding the testimony and rightly so. [caselaw.findlaw.com]

The judges on the 10th Circuit used an unfortunate choice of words, however. That was the case where they said "pyrolysis" doesn't happen, when what they meant was "there is no such thing as pyrophoric carbon." The existence of pyrophoric carbon has never been demonstrated.

There is often a problem when judges try to be scientists but there is a bigger problem when an expert uses "spalding" and "shiny alligatoring" to send someone to prison.