LOTO and LOTOTO: A guide to safe energy management

Lock Out, Tag Out (LOTO) and Lock Out, Tag Out, Try Out (LOTOTO) are essential safety procedures in industry to protect you from the hazards of unexpected energy release. Although the terms are often used interchangeably, there are clear differences between the two concepts that are critical to the effectiveness of your safety policy.

In this article, we’ll discuss the difference between LOTO and LOTOTO, the benefits of both methods, what is legally required, and how to choose the right approach for your organization.

The difference between LOTO and LOTOTO

LOTO stands for Lock Out, Tag Out. It is a procedure where energy sources of machines or equipment are physically isolated (Lock Out) and equipped with clear warning tags (Tag Out). This process is intended to prevent accidental machine startup during maintenance work.

Key features of LOTO:

  • Lock Out: Placing physical locks on switches, valves, or other energy isolation points.
  • Tag Out: Attaching a label that warns that the energy source must not be activated.

LOTO primarily focuses on isolating energy sources but does not include direct control or validation to ensure the isolation is effective.

Lock Out Tag Out

LOTOTO builds on the LOTO process by adding a crucial extra step: Try Out. This means that, after isolating the energy source, you check whether the machine is actually fully turned off and secured. This additional control process makes LOTOTO a more robust and safe method, especially in complex environments with multiple energy sources or higher risks.

Why choose LOTOTO?

While LOTO already provides a strong safety foundation, LOTOTO is often the better choice in many situations. Here’s why:

1. Confirmation of safety

LOTO might mistakenly assume that an isolated energy source is automatically safe. By adding a Try Out step, you eliminate this uncertainty and confirm that the system is genuinely turned off.

2. Complex energy sources

In modern industrial installations, machines often have multiple energy sources (electrical, hydraulic, pneumatic). A Try Out helps ensure that all these energy sources are effectively isolated.

3. Compliance with higher safety standards

Increasingly, regulations and standards like ISO 45001 encourage more comprehensive approaches like LOTOTO to minimize risks further.

Legal requirements

In many countries, safety procedures like LOTO and LOTOTO are legally required. Here’s what is specifically mandated under different regulations:

  • European Union: The European Machinery Directive (2006/42/EC) and the Occupational Health and Safety Act require employers to make machines safe during maintenance. LOTO is considered a minimum requirement, but the directive also states that risks must be fully eliminated. Although the Try Out step is not explicitly mandatory, it is recommended as part of a robust risk assessment.
  • Belgium: The Codex on Well-being at Work mandates that energy sources must be switched off and secured during maintenance. LOTO is a required basic principle, while the Try Out step is encouraged as a best practice to meet the general duty of care.
  • International Standards: ISO 45001 requires organizations to implement procedures to minimize risks. LOTOTO is seen as an advanced method to comply with this standard, although the exact implementation may vary depending on the risk assessment.
  • United States: OSHA Standard 1910.147 specifically mandates the use of LOTO during maintenance work on machines. The Try Out step is recommended as part of the standard but is not always explicitly required. However, its absence may be considered negligence in the event of an incident.

How to implement LOTOTO

Implementing LOTOTO requires extra attention to detail, training, and control mechanisms. Follow these steps for successful integration:

  1. Identify all energy sources: Create a complete inventory of machines and their energy sources.
  2. Develop specific procedures: Describe step by step how Lock Out, Tag Out, and Try Out should be performed.
  3. Invest in suitable equipment: Ensure durable locks, clear tags, and tools for testing isolation.
  4. Train your employees: Teach them not only LOTO but also the importance of the Try Out step.
  5. Evaluate and improve: Regularly audit procedures to ensure they are correctly followed and remain effective.
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