2010年7月16日,《关于珠江三角洲地区执行第四阶段国家机动车大气污染物排放标准的通告》由广东省环境保护厅、广东省经济和信息化委员会、广东省公安厅、广东省质量技术监督局、广东省工商局等五部门联合发布。从去年就一直备受业界人士关注的国Ⅳ话题,终于有了一个明确的官方信息表达。通告规定6月1日至8月31日为过渡期,从9月1日起 July 16, 2010, “on the implementation of the fourth phase of the Pearl River Delta region, the state motor vehicle air pollutant emission standards notice” by the Guangdong Provincial Environmental Protection Agency, Guangdong Provincial Economic and Information Technology Commission, Guangdong Provincial Public Security Bureau, Guangdong Province Quality Technical Supervision, Guangdong Provincial Administration of Industry and other five departments jointly issued. From the last year, the country has been much concerned about the national industry IV topic, and finally has a clear official message. The circular provides June 1 to August 31 for the transition period, from September 1 onwards