international prohibition sign International No Smoking SymbolInternational Prohibition Sign

The photo shown from the left post is a circle backlash symbol which is the accepted “no symbol” by the International Organization for Standardization (ISO). By using this sign, the red area must take up at least 35% of the total area of the sign within the outer circumference of the “prohibition sign”. So 35% of everything within the outer edge of the “no symbol” must be the symbol itself. This means that when using this prohibition symbol, any image shown must be inside the circle and backlash.

International No Smoking SymbolNo Smoking Symbol or Button

Looking from the no smoking photo, their is no standand or correct symbol representing the prohibited use of cigarette. When you search for no smoking logos around, you may find different pictures or varieties about no smoking. All of them are valid representation as long as the message is clear and follows the guidelines of the International no symbol.