Implementing LOTOTO Best Practices in Ammonia Systems | Blog No. 89

Lockout/Tagout/Tryout (LOTOTO) is a critical safety practice, especially in ammonia

refrigeration systems, to prevent accidental release of hazardous energy during

maintenance. Implementing LOTOTO effectively requires attention to detail, clear

procedures, and thorough training. Below are some best practices to follow to ensure the

safety of personnel working with ammonia systems.

1. Develop Clear Procedures

Tailor your LOTOTO procedures specifically for your ammonia refrigeration system, aligning

with OSHA’s guidelines under 29 CFR 1910.147. These procedures should include steps for

isolating ammonia flow at critical points, methods for depressurizing system components,

and procedures for safely venting residual ammonia. Clear and specific procedures help

reduce the risk of accidents and ensure that maintenance can proceed without incident.

2. Use Approved Devices

A Lockout/Tagout/Tryout (LOTOTO) tag should include the authorized worker's name or ID,

the reason for the lockout (e.g., maintenance or repair), and the date (and time, if

applicable) the lockout was applied. It should also display a warning, such as "Do Not

Operate" to ensure equipment remains off-limits and contact information for the person

who applied the lockout. Additionally, each tag should have a unique lock or tag number for

tracking. These elements ensure proper communication and safety during the lockout

process.

3. Train Your Team

Comprehensive training is essential for effective LOTOTO implementation. Training should

cover the recognition of energy sources specific to ammonia systems, an understanding of

The hazards associated with liquid and vapor ammonia, and the proper use of Personal

Protective Equipment (PPE), as outlined in 29 CFR 1910.132. By equipping workers with the

knowledge and skills needed, you ensure they are prepared to safely perform their duties

and understand the potential risks involved in working with ammonia.

4. Use Group Lock Boxes

For large-scale maintenance tasks involving multiple workers, group lock boxes (or satellite

boxes) are a useful tool. These devices allow several workers to secure their

locks on a single lockout point, ensuring that every team member verifies isolation before

beginning work. This practice promotes the "one lock per person" principle and reinforces

accountability, as outlined in OSHA’s standards.

5. One Lock, One Key

Each employee must be equipped with their lock and key. OSHA mandates this to

ensure accountability and safety—no lock can be removed without the employee’s explicit

action, preventing the accidental or premature re-energization of equipment. This practice

is fundamental for maintaining control over the lockout process and ensuring that no

worker is at risk from uncontrolled energy release.

6. Verify Isolation

Never assume that a system is properly isolated—always test and verify. This step involves

using ammonia detectors, pressure gauges, and visual inspections to confirm that the

The system is properly isolated. As required by OSHA, the verification of isolation and de-

energization must be done to ensure no residual energy remains in the system. This is an

essential part of maintaining worker safety and preventing accidents during maintenance.

7. Tryout

After verifying isolation, always perform a "tryout." This step involves attempting to operate

the equipment to confirm it cannot start or move. It’s crucial in verifying that all forms of

hazardous energy—such as electrical, mechanical, or pneumatic—have been fully

isolated. If the equipment operates, it indicates that isolation was not successful, and

additional isolation steps are required before proceeding. The tryout ensures that the

equipment is completely de-energized, preventing unexpected starts that could lead to

injury. You should never continue with the LOTOTO process until you have

"tryout" all the isolated equipment.

8. Communicate Clearly

Clear communication is key when implementing LOTOTO. Ensure all team members are

aware when LOTOTO is active and that they understand the risks involved with the isolated

equipment. Display clear signage around isolated equipment and communicate these

risks during team meetings or shift changes. Consistent and effective communication

ensures everyone involved is on the same page, reducing the likelihood of mistakes or

misunderstandings.

By adhering to these best practices, including the crucial tryout step, you can help ensure

that maintenance on ammonia systems is performed safely and in compliance with OSHA

regulations. Proper implementation of LOTOTO not only protects workers but also helps

maintain the integrity and functionality of the system, promoting a culture of safety and

accountability. At the end of the day, we all want to see our loved ones when we return

home, so let’s build a safety culture together.

Stay tuned for more!

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