Introduction to Safety Basics: A Series | Part 2: Lockout/Tagout/Tryout | Blog No. 72

[This is 2 of 3 in the Introduction to Safety Basics: A Blog Series by one of our excellent PSM Consultants, Riley Masters]

Introduction Blog

In ammonia refrigeration systems, safety is paramount. One of the most effective and

lifesaving procedures for ensuring safety during maintenance or servicing is

Lockout/Tagout/Tryout (LOTOTO). This method goes beyond simply meeting compliance

requirements—it is a critical safety measure that protects workers from hazardous energy

releases and potential ammonia exposures, both of which can be fatal if not managed

properly.

What is Lockout/Tagout/Tryout (LOTOTO)?

Lockout/Tagout/Tryout involves isolating energy sources such as electrical, hydraulic, or

pneumatic systems before performing maintenance or repair work. The procedure ensures

that machinery or equipment is fully de-energized and remains inoperable until all work is

safely completed. In ammonia refrigeration systems, however, the stakes are higher. These

systems typically operate under high pressures and utilize ammonia, a toxic and

flammable substance that is classified as hazardous under OSHA’s Process Safety

Management (PSM) Standard (29 CFR 1910.119). Failure to properly isolate energy sources

can result in ammonia leaks, which put workers at risk of serious injuries such as chemical

burns, respiratory damage, or even death.

Why is LOTOTO Crucial in Ammonia Refrigeration?

Ammonia refrigeration systems are intricate and require careful attention to ensure safety.

Without proper energy isolation, a number of dangerous scenarios can arise. Equipment

may unexpectedly restart, causing severe injuries or fatalities. Uncontrolled ammonia

releases could lead to harmful exposures or catastrophic events, violating OSHA’s

Hazardous Energy Control Standard (29 CFR 1910.147). Furthermore, non-compliance

with LOTOTO procedures can result in costly fines, operational downtime, and significant

reputational damage. For instance, during maintenance tasks such as pump repairs or

valve replacements, residual ammonia trapped in the system poses a significant risk.

Proper implementation of LOTOTO ensures that valves are properly isolated, pipelines are

depressurized, and workers are protected from the potential dangers of ammonia

exposure. This makes LOTOTO an essential procedure for maintaining both worker safety

and system integrity in ammonia refrigeration systems.