| CLEAN | Citizens Learners Educators Against Neglect | 公民学习者教育者反对忽视 |
| CLEAN | Commonwealth Law Enforcement Assistance Network (Pennsylvania) | 联邦执法援助网络（宾夕法尼亚州） |
| CLEAN | Closed Loop Environmental Alliance Network | 闭环环境联盟网络 |
| CLEAN | Comprehensive Long-Term Environmental Action Navy | 综合长期环境行动海军 |
| CLEAN | Community Led Environment Action Network | 社区主导的环境行动网络 |
| CLEAN | Campbell Local Emergency Action Network | 坎贝尔当地紧急行动网络 |
| CLEAN | Children Learning Environmental Awareness Now | 儿童现在学习环境意识 |
| CLEAN | Citizens League For Environmental Action Now | 公民环保行动联盟 |