A warning tone can be heard when the program starts. These programmes cannot be shown on free to air television before 10 PM and after 6 AM. Unrated programmes do not display any icon on the screen; in Catalonia, TP-rated shows do not show any icon as well. Nowadays rating symbols are shown during all the programme and in promos; each channel has its right to choose its design and where it has to be placed. The "Infantil" rating it's the exception, because it appears during the first five seconds. In Catalonia, only the 13, 16 and 18 ratings remain transparent in the screen, while the others (7, 10 and 12) are seen during the first 30 seconds. Taiwan Taiwanese rating system for television programmes was introduced on 1 January 1999 with four symbols represented with four Chinese characters 普 for General, 護 for Protected, 輔 for Parental Guidance and 限 for Restricted, but changed on 13 June 2017 to unify the television age rating with Taiwan's video game and motion picture ratings, and there are five symbols, 0+: 普遍級(普) (General level) : suitable for watching by general audiences. Television programmes free of circumstances listed in the preceding four articles and suitable for watching by general audiences may be listed as G . The images of news reports shall conform to the provisions of "G" rate. 6+: 保護級(護) (Protected level) : not suitable for viewing by children under the age of six; children over six and under the age of twelve can view if accompanied by parents, teacher or an adult relative. Television programmes free of circumstances listed in the preceding three articles but portraying any one of the following circumstances shall be listed as P. The portrayal of fighting, larceny, terror, abnormal social phenomenon. The portrayal of sexual encounters or confused ethics and values. Other content that has a detrimental influence on the behaviour or psychology wellbeing of children under the age of six. 12+: 輔導十二歲級(輔12) (Parental Guidance-12 level) : not suitable for viewing by children under the age of twelve, split from the former rating Parental Guidance. Television programmes free of circumstances listed in the preceding two articles but portraying any one of the following circumstances shall be listed as PG-12. Plots or dialogues that portray crime, violence, terror, blood, abnormality, strangeness or social deformity or other phenomenon, the portrayal of which is slight. Content that uses action,