This part of ISO 20567 specifies three methods for the evaluation of the resistance of automobile finishes and other coatings to chilled-iron grit projected onto the surface under test to simulate the impact of small stones.
ISO 20567-1:2005 history
2017ISO 20567-1:2017 Paints and varnishes - Determination of stone-chip resistance of coatings - Part 1: Multi-impact testing
2005ISO 20567-1:2005 Paints and varnishes - Determination of stone-chip resistance of coatings - Part 1: Multi-impact testing