Valdkond ICAO lisade põhjal loodud klassifikaatori järgi: Õhusõidukid
Kui rikete analüüs näitab, et osa peab säilitama eriti kõrge töökindluse taseme ja selle osa rikked esinevad ainult äärmiselt ebatõenäolisel juhul, siis seda õhusõiduki osa nimetatakse kriitiliseks.
Hea teada
Where the failure analysis shows that a part must achieve and maintain a particularly high level of integrity if Hazardous Effects are not to occur at a rate in excess of Extremely Remote then such a part shall be identified as a Critical Part.
In addition to the requirement of point 21.A.804, each manufacturer of a part to be fitted on a type-certificated product which has been identified as a critical part shall permanently and legibly mark that part with a part number and a serial number.