เสียงที่ใช้ร่วมกัน

signage (Warning / Prohibitor / Mandatory) “Warning Signs: triangle, black on yellow, black border — warn of hazards. Prohibitor Signs: red circle with oblique on white — prohibit risky behavior. Mandatory Signs: blue circle, white pictogram — actions required to safeguard health and avoid injury.” “Spot the shape, know the action: triangle warns, red circle forbids, blue circle instructs. Follow signs immediately.”