A close-up image of a door with a sign containing four icons indicating prohibited activities. The icons include a mobile phone with a crossed-out circle, a person smoking with a crossed-out circle, a flame with a crossed-out circle, and a person with a crossed-out circle. The sign reads "Use of Mobile Phone Prohibited, Restrict Area Authorized Only, No Smoking, No Fire Naked Flame". This image can be used to convey restrictions in public areas or workplaces, emphasizing the importance of following safety guidelines.