If your employees are required to be tested under DOT regulations, then no notice period is required. Your company is, however, required to post certain required information and provide your employees with Employee Education handouts regarding the federal regulations and your company’s drug and alcohol testing program. The Compliance Manual provided with membership contains all the necessary posters, documents, handouts, forms and training materials required by the DOT to be posted and provided to your safety-sensitive employees.
Non-DOT employers are generally advised to provide at least 30 or 60 days notice. You will want to consult your HR professional or employment attorney.