Various sources (e.g., Wikipedia and WorkSafely) claim that the seven color combinations commonly used for barricade tape (a.k.a. caution tape) and safety markings in North America (yellow and black for physical hazards, green and white for first aid supplies, etc.) are specified by the US Occupational Safety and Health Administration (OSHA). OSHA standard 1910.144 ("Safety color code for marking physical hazards") is often mentioned. However, 1910.144 states only the following regarding color:
- The color red should be used to identify fire protection equipment, sources of danger, and emergency stop controls.
- The color yellow should be used to mark physical hazards.
Are the seven color combinations specified in another OSHA standard? (If so, I haven't been able to find it.) If not, where did they originate?