Does the fire rating apply to the AT9012 FR downlight alone?

No. This is one of the most important points to understand. Fire resistance is a system rating, not a product rating. The FRL of _/120/120 applies to the downlight as tested within a specific ceiling construction assembly — including specific plasterboard types, joist types and fixing methods, as defined in the test report.

Installing the AT9012 FR in a ceiling system that differs from the tested configuration may not maintain the rated FRL. An accredited person must assess compatibility between the luminaire and the actual site ceiling construction.

Key principle: A fire-rated downlight installed in an untested or incompatible ceiling system does not automatically make the ceiling fire-rated. The entire assembly must be validated.