tailgate一般是后挡板的意思，直译过来就是“后挡板安全问题会议”和“后挡板安全问题概要”。可能是石油提炼或者运输过程中使用的某器械的后挡板问题吧？具体细节不知道，只好直接意译了。希望能解答你的疑问。
For example, if you notice that spills are not being cleaned up promptly, hold a tailgate safety meeting to discuss housekeeping policies. If an accident or a near-accident occurred at your jobsite, share the details and corrective actions during a tailgate safety meeting. Try to answer the ...