contamination free

• 无污染的

contamination free的用法和样例：

例句

1. Respirators should only be removed when the wearer is in an area that is considered free of airborne hazards, including confirmed or suspected influenza patients.
   呼吸防护口罩只能在无污染的环境中，包括无确诊或疑似流感病人的环境中摘除。