What is the function of lockout/tagout systems?

• A. Allow temporary re-energization of machinery during maintenance
• B. Prevent unauthorized activation of machinery or electricity
• C. Improve housekeeping at the site
• D. Provide routine maintenance signals

Answer: (B)

Lockout/tagout systems isolate hazardous energy during service or maintenance, so machinery cannot start or release stored energy while someone is working on it. A lockout device physically attaches to the energy-disconnecting mechanism, preventing re-energization, while a tag provides a warning that the equipment is out of service. This ensures that only the authorized person who applied the lock can re-energize the system, and only after the work is safely completed and the energy state is verified zero. It’s specifically about preventing unauthorized activation of electricity or other energy sources, not about housekeeping or signaling routine maintenance, and not about temporarily re-energizing equipment during work.