AWS Certified Welding Inspector — FundamentalsSafetyMedium

A welding inspector is overseeing a maintenance task where a welder needs to work on a large, stationary piece of equipment that is electrically powered. To prevent accidental startup during welding, what is the MOST appropriate safety procedure that must be implemented?

  1. AAssigning a dedicated person to monitor the equipment's controls.
  2. BImplementing a Lockout/Tagout (LOTO) procedure for the equipment's energy source.
  3. CPlacing 'Do Not Operate' tags on the equipment's controls.
  4. DDisconnecting the power cord from the equipment's outlet.
Show answer & explanation

Correct answer: B. Implementing a Lockout/Tagout (LOTO) procedure for the equipment's energy source.

Lockout/Tagout (LOTO) is the most comprehensive and legally mandated procedure for de-energizing equipment and preventing accidental startup during maintenance or service. It ensures the energy source is isolated and locked, making accidental re-energization virtually impossible.

Why the other options are wrong

  • A. Monitoring is a administrative control and relies on human vigilance, which is less reliable than positive energy isolation.
  • C. Tags alone are warnings and can be ignored or accidentally removed, not providing positive isolation.
  • D. Disconnecting a power cord is a good step but does not guarantee the circuit cannot be re-energized, especially for hard-wired equipment or if the plug is accessible for re-insertion.

Lockout/Tagout (LOTO)

A safety procedure used to ensure that dangerous machines are properly shut off and not able to be started up again prior to the completion of maintenance or service work.

  • Physically isolates energy sources.
  • Prevents accidental startup.
  • Mandated by OSHA for hazardous energy control.

Memory trick: Lock it out, tag it tight, keep the power from seeing the light.

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