When can you ask employees about their prescriptions?

Issue: The Staten Island Ferry crash in October raised the issue of when you can investigate employees' prescription use.

Risk: You could spark an ADA suit by asking too many questions about prescription use, and a negligence suit by asking too few.

Action: Ask workers in safety-sensitive jobs to disclose any medications they take that could impair their work performance.

When the Staten Island Ferry crashed into the docks in October, killing 10 people, the assistant captain at the helm apparently had passed out. While investigators haven't yet finalized the cause, they're looking at whether blood pressure medication the assistant captain took that morning, one of six prescription medicines he took, caused him to collapse.

The incident raises this question for employers: How deeply can you delve into employees' prescription medicine use?

ADA limits your questioning. Most employers shy away from asking about medical conditions and treatments, and with good reason. The Americans with Disabilities Act (ADA) says you can't ask applicants medical questions (including prescription usage) before you make a conditional job offer.

But in certain cases, it may be necessary to require people in safety-sensitive jobs to report if they're taking medication that can affect their ability to perform the job's essential functions. In those limited cases, you must prove that the employee's failure to take the medication, for example, would pose a direct threat to public safety.

Also, organizations regulated by federal safety laws, those that employ bus and truck drivers, for example, are free to inquire about disabilities and prescription use affecting the job.

Bottom line: Focus on safety. You can't go on a fishing expedition asking about prescription drugs. It's better to ask current employees whose jobs depend on safety to disclose and identify in a more general way any medications that could impair their performance and put people at risk.

For more advice on such inquiries, see the EEOC's Enforcement Guidance on Disability-Related Inquiries and Medical Examinations at www.eeoc.gov/docs/guidance-inquiries.html.