Contamination是什么意思

客户的问卷调查表中有如下问题:

Do you have operating procedures to prevent the contaminations of the substances with environmental impacts when used?

偶认为客户是在问有没有程序来防止产品受到限制物质的污染, 所以偶回答:

Yes. We select several important raw materials that we think could possibly contaminate the bumped wafer and we ask the suppliers provide RoHS data.

偶的老板认为偶是错的, 给了另一个答案:

All the wet chemical benches have designed with 2nd containment structure to eliminate the possibility of pollution incidence caused by tank leaking, and all the collected chemical waste materials are transferred to professional waste treatment co..

你认为客户在问什么? 你会如何回答? 谢谢!