where required是什么意思

在需要的地方
双语对照
例句:
1.
Acceptance criteria shall be defined by the organization and,where required,approved by the customer.For attribute data sampling,acceptance criteriashall be zero defects.
组织必须确定接收准则,顾客要求时,必须由顾客批准.对于计数型抽样,接收水平必须是零缺陷.