A potential employer who has at least 15 employees (and is therefore covered by federal laws against disability discrimination) cannot require a job applicant to take such a test before offering the applicant a job.

You must offer a job to a potential employee before requiring him or her to take a medical or physical examination. You might then be able to reject the potential employee if the exam shows that he or she cannot perform the essential job functions with or without a reasonable accommodation. Remember: If you reject the potential employee after failing the exam, then he or she will know that the only reason for the rejection was the exam. Therefore, you must make sure not to deny employment due a disability revealed during the exam, as long as the potential employee's disability may be reasonably accommodated without an undue hardship to your business.

The exam must be related to the work the employee will be doing. For example, if you are hiring an office receptionist, you normally shouldn't ask the applicant to lift 75-pound weights as part of the medical exam. On the other hand, if you are hiring for a parcel service job, you might be able to reject an applicant that can't lift a 75-pound weight.

Confidentiality
Pre-employment drug test

Confidentiality

Generally, the results of the exam must be kept in a file separate from the employee's regular personnel file and should not be revealed to anyone except a medical practitioner, such as the company doctor or, with the employee's consent, the employee's personal physician.

Can I require an applicant to take a pre-employment drug test?

States have differing laws regarding drug tests. Generally, drug tests are permitted for applicants for all types of jobs, even jobs that are not "safety sensitive."