Before their first day of school, German children get a Schulranzen, a school satchel. The standard DIN 58124 requires that 10 percent of the visible surface of a satchel be retroreflective and 20 percent fluorescent.
The German Social Accident Insurance explains the reason: drivers often see people in dark clothing only at less than 25 meters. Stiftung Warentest adds: “Die Schulranzennorm ist allerdings kein Gesetz.” The satchel standard is not a law.