Kushal Aurangabadkar is engineering manager at Cargill. Views are the author’s own.
Ammonia is the backbone of food processing, cold-chain and other operations relying on refrigeration systems. Yet even well-managed facilities with competent engineers overseeing compliant operations can suffer from preventable safety and performance issues. The surprising culprit isn’t equipment failure or lack of training; it’s something more basic: operational information that never reaches the right person at the right time.
Common scenario
In a recent incident, operators at a food product facility recorded steadily rising condensing pressures in their refrigeration system. Nothing dramatic, just a gradual upward trend over several shifts. Everything was noted correctly in the logbook. The issue was even mentioned during handover during shift change meetings. Still, no one escalated the findings. Why? Because the system was running. No alarms. No trips. No incident.
Four nights later, the pressure rise forced compressors to unload, causing temperature swings in a blast freezer and coolers, impacting operations and food product safety. The incident was dangerously close to becoming an incident requiring relief even though nothing failed mechanically. The system had failed communication-ally.
This scenario is more common than many familiar with these systems admit.
Structural weakness
Among teams managing refrigeration systems, a pattern shows up repeatedly:
- Operators collect data and maintain a logbook
- Maintenance teams resolve tasks
- Engineers review trends after the fact
But no one has the responsibility of interpreting subtle deviations early. The result? A perfectly logged problem with no actionable follow-through.
For teams facing energy efficiency and compliance pressures, this gap between observation and action is more than inconvenient; it’s costly and risky and could lead to a significant event.
Practical fix
As an engineer for Cargill, the food systems company, I’ve been involved in an effort to implement a simple, structured escalation model that has improved system performance. The model addresses process safety management, or PSM, concerns in three steps.
First, it defines “abnormal” in measurable terms. Instead of relying on intuition, it establishes clear triggers, including indicators like these:
- Condensing pressure at +10 psi above a rolling baseline
- Repeated oil return alarms
- Vessel levels drifting outside normal operating conditions
- Slight vibration and noise in compressors or pumps
- Routine frost or ice patterns in odd locations
- Random programmable logic controller/human-machine interface glitches or set point drift
- Faint ammonia odor near equipment
- Normal condenser/air handling unit performance degradation
The list can go on. The point is that, when these indicators appear, they’re automatically flagged as process safety management-relevant anomalies, not routine observations.
Second, it creates one clear escalation point, a single, accountable role, to own the situation. The person can be a refrigeration supervisor, engineering manager or project safety management (PSM) lead. In this role, the person, not whoever is on call, evaluates all abnormal conditions. This eliminates the not-my-responsibility grey zone.
Third, it requires the point person to address each flagged condition within 24 hours. Each anomaly receives one of the following:
- Operational adjustment
- Maintenance work order
- Engineering review
- Temporary safeguard
- Short-term monitoring plan
Nothing disappears into the logbook abyss. Within weeks of implementing the model, early trend detection uncovered a number of issues that, if left unaddressed, could have escalated into an incident:
- A condenser fan motor bearing and the shroud nearing failure
- A sticking liquid overfeed valve
- A miscalibrated float threatening vessel stability
- Low liquid vessel levels over the weekend due to load misdistribution
- An engine room PLC communication issue
These issues were caught before they caused energy losses, temperature non-compliance or ammonia releases. For plants operating under tightening safety expectations, this kind of structured communication is a low-cost, high-impact improvement.
Clear pathway
In ammonia refrigeration, major incidents rarely hinge on dramatic failures. They usually start with small, visible signals that nobody formally owns. If teams want safer, more reliable refrigeration operations, the solution isn’t more paperwork; it’s clearer pathways for elevating the early warning signs we already capture.
Strengthening these communication loops offers a tangible, immediate boost to plant safety, system stability and energy performance.
