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There is no 14 CFR 91 or 14 CFR 135 requirement for any fire coverage at all at the airports these operators use, but some companies have instituted such requirements. Even if you don’t have such a requirement, knowing your aircraft’s Airport Rescue and Fire Fighting (ARFF) code may help you decide between two airports of otherwise equal attractiveness. A G450, for example has a US code of A and an ICAO code of 5. A G550 raises these to a US code of B and an ICAO code of 6.
Everything here is from the references shown below, with a few comments in an alternate color.
2020-12-26
[ICAO Annex 14, Table 9-1]
Portions of this page can be found in the book International Operations Flight Manual, Part VIII, Chapter 2.
14 CFR 139, Title 14: Aeronautics and Space, Certification of Airports
ICAO Annex 14 - Aerodromes - Vol I - Aerodrome Design and Operations, International Standards and Recommended Practices, Annex 14 to the Convention on International Civil Aviation, Vol I, Eighth edition July 2018
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