Use the relevant performance category
ACT treats colourfastness to light as a separate performance topic. A pleasing colour photograph or a dark shade does not provide a light-exposure result. This article uses that technical distinction without assigning a test rating to a Mingpin reference or predicting service life.
Describe the room rather than guess
Our recommendation is to record whether seating is beside glazing, the likely duration of direct light and whether curtains or shades are normally used. Ask the supplier for the applicable report, test conditions and tested colour. Where exposure is demanding, have the responsible project specifier set the acceptance criterion.
Keep visual and technical approvals together
Approve a real swatch under the project lighting, but retain the separate performance evidence beside it. Do not describe a showroom comparison as an accelerated test. MPY0454 illustrates a matte visual palette only. Its photo establishes neither outdoor suitability nor a lightfastness rating; request current data for the exact reference and colour.