China a has a four-tier color-coded warning system for severe weather, with red being the most serious, followed by orange, yellow and blue.

中国对极端天气有一套四级预警系统，用四种颜色分别表示等级不同的预警，其中红色为最，其次是橙色、黄色和蓝色。 。

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Medical teams planned for the births for months, even designating a special "Code 5" designation, handing out pagers to staff and developing a color-coded system to match each baby with his or her needed supplies.

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"The Color-coded Threat Level System is used to communicate with public safety officials and the public at-large through a threat-based, color-coded system so that protective measures can be implemented to reduce the likelihood or impact of an attack, " according to the DHS Web site.

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Authorities have also introduced a color-coded warning system to alert residents about dengue outbreaks in specific districts.

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