When is it permissible for a collector to require the donor to remove their clothing during a urine collection?

The correct answer is that it is permissible for a collector to require the donor to remove their clothing when there are reasonable grounds for suspecting tampering. In drug testing situations, maintaining the integrity of the sample is crucial. If a collector has valid concerns that a donor might attempt to tamper with the urine sample—such as smuggling in a substitute sample or using adulterants—then requiring the donor to undress can help ensure that the specimen provided is legitimate.

This protocol helps to uphold the reliability of the testing process, thereby serving to deter attempts at cheating or falsifying results. It's important to note that any such request must be based on observable behaviors or other indicators that justify the suspicion of tampering, ensuring that the approach remains fair and justified within the context of the collection process.