Which item must be included on a lockout/tagout caution tag?

• A. Authorized signature
• B. Date
• C. Authentication and date/time
• D. Device serial number

Answer: (C)

The key idea here is accountability and timing in tagout tagging. A caution tag marks equipment as not to be operated and guides safe re-energizing, so it must clearly show who placed the tag and when it was placed. Including both authentication (the person’s identifier) and the date/time provides a traceable record of responsibility and the exact moment the control was applied, which is essential for coordinating removal and verifying safety before re-energizing. A date alone fails to identify who placed it, a signature alone may not capture the exact time, and a device serial number doesn’t indicate who applied the tag or when. Hence, authentication and date/time best meet the safety and accountability needs.