Is there a possible error in the definition of a "Cryogenic Fluid"?

The IFC, NFPA 400, and NFPA 55 all define a cryogenic fluid as "A fluid having a boiling point lower than -130°F at 14.7 pounds per square inch atmosphere (psia) (an absolute pressure of 101.3 kPa)."

Following that exact wording of this definition, virtually every gas would be considered a Cryogenic Fluid. Fluids, while not defined by any codes, are either gases or liquids.

The air we breathe has a boiling point of -317°F at 14.7 psia. Air is a fluid.

Clearly, this is not the intent of the ICC or NFPA. The NFPA Handbook indicates that a cryogenic is a liquified gas kept below 130°F. The definition should be changed to "a liquid having a boiling point under...." from "a fluid having a boiling point under...."

Have any fire protection professionals ran across a situation like this where the strict definition was incorrect? How did you handle it?

I am considering just making a paragraph in my report explaining my logic and going along with my day. Or would you not even bring this up with the AHJ because the intent is clear?

Thanks in advance.

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We have a closed ammonia refrigeration system for a large cooler/freezer. The refrigeration equipment is located in a separate mechanical room. Total amount of ammonia is less than 10,000 lbs.

My question is explosion control per Section 911 of the International Fire Code required for the refrigeration mechanical room?

I am reading different interpretations on whether ammonia is considered a flammable gas, most say it is technically not a flammable gas but can burn and/or explode.

I'm interested in hearing everyone's take. Thanks.

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