A prohibition sign is a safety symbol characterized by a red circle with a 45-degree diagonal line from upper-left to lower-right. It is used to indicate that a specific action or behavior is not allowed. This sign often overlays a pictogram or may be accompanied by text to clearly communicate the prohibited activity, serving as a visual cue to prevent unsafe or unauthorized actions.
Appearance and Design Standards
The prohibition sign typically has a red circular border and diagonal line, with the background in white and the pictogram or text in black. According to the ISO 3864-1 standard, the red area must cover at least 35% of the sign's area, with the diagonal line's thickness being 80% of the circle's band width. The diagonal runs from the upper left to the lower right within the circle.
Common Uses
- Traffic signs (e.g., no left turn, no U-turn, no parking)
- Public safety (e.g., no smoking, no littering, no swimming)
- Workplace safety (e.g., no entry, no mobile phones, no food or drink)
- Packaging and product warnings (e.g., do not drop, keep away from magnets)
- Promotional symbols indicating prohibition (like pest control logos).
Legal and Safety Importance
Prohibition signs are mandated by health and safety regulations in many countries for workplaces, public areas, and industrial settings. They help reduce accidents, protect health, prevent unauthorized access, and ensure compliance with safety laws such as the Health and Safety (Safety Signs and Signals) Regulations in the UK.
Unicode Representation
The prohibition sign is also recognized in Unicode, with U+1F6C7 🛇 being the prohibited sign symbol, and combination characters exist for overlaying the prohibition slash on other symbols or letters to indicate prohibition.
This clear, universally recognized visual indicator plays a crucial role in safety communication worldwide.
