In industrial ammonia (R-717) refrigeration systems, choosing the right valve isn’t just a design preference; it’s a safety-critical decision. Ammonia is toxic, mildly flammable, and typically flows through the system at elevated pressures while constantly shifting between liquid and vapor phases. If the wrong valve ends up in the wrong location, the result can be excessive pressure drop, unstable control, trapped liquid expansion, or fugitive emissions. Understanding how glo

Planning for an emergency at a refrigeration facility can be a daunting task, particularly when deciding whether to prepare an Emergency Action Plan (EAP) or an Emergency Repose Plan (ERP). Choosing the best option depends on several factors, including the placement of responsibility for response, the facility’s desire to maintain trained responders onsite, the financial burden for training, and whether the local fire authority can provide timely incident response. In truth,

In ammonia refrigeration, removing non-condensable gases is not optional maintenance; it is essential for system performance. Air and other non-condensables raise discharge pressure, increase compressor workload, and reduce overall capacity. Over time, even small amounts can translate into measurable energy penalties and unnecessary mechanical stress. The two primary methods for removing these gases are manual purging and automatic refrigerated purging. Both methods are used

If you’ve worked around modern industrial ammonia refrigeration systems, you’ve likely encountered a plate-and-frame heat exchanger. While shell-and-tube exchangers have long been the workhorse of the industry, plate-and-frame units have become increasingly common where efficiency, tight temperature control, and space savings are priorities. Plate-and-frame heat exchangers are widely used in ammonia systems for ammonia-to-water or ammonia-to-glycol chillers, heat recovery app

If you’ve spent any time around industrial ammonia refrigeration, you’ve seen a shell-and-tube heat exchanger. It is one of the most common ways to transfer heat between two fluids without letting them mix, and it appears throughout ammonia systems. Shell-and-tube heat exchangers show up all over industrial ammonia refrigeration because they can serve many duties in one durable package. You may see them as water-cooled condensers, where hot, high-pressure ammonia vapor is con

I’ve been in a lot of facilities that technically have piping colors, but no visual legend to explain what those colors actually mean. Especially as a recent graduate getting started in the ammonia PSM industry, which turned machinery rooms into instant mazes instead of functional workspaces. You’d see blue, yellow, orange, and green everywhere—but without a key, none of it told a story. It was just paint on the pipe. In an ammonia machinery room, piping density is high, and

For facilities operating ammonia refrigeration systems, January 1, 2026, is more than a future date on the calendar. It represents a clear line between proactive compliance and regulatory exposure. By that date, existing ammonia refrigeration systems are expected to have completed a Minimum System Safety Evaluation (MSSE) in accordance with IIAR 9. This is not a theoretical expectation or an optional safety exercise. Failing to complete An MSSE is a compliance issue with real

In modern industrial refrigeration, reliability and capacity are critical. Among the various compressor designs available, rotary screw compressors have become the preferred solution for large-scale applications. Their ability to deliver high capacity with fewer moving parts has made them a cornerstone of today’s industrial refrigeration systems. Understanding Rotary Screw Compressors  Rotary screw compressors were originally developed in the 1930s; however, early versions we

There is a persistent misconception in the agricultural ammonia world that bulk distribution facilities with large bullet tanks are “exempt” from federal process safety rules. This belief often comes from partial or outdated interpretations of OSHA and EPA exemptions. In reality, while certain exemptions do exist, they are narrow, and misunderstanding them can leave facilities unintentionally out of compliance. This article explains how anhydrous ammonia is used in agricultur

The first episode of The Cold Truth Podcast  kicks off with hosts Mike and Eli sitting down with Ryan Reardon, founder of R2 Mechanical Consultants, for a thoughtful and wide-ranging conversation on industrial refrigeration, system selection, and where the industry is headed. Whether you’re an owner, engineer, contractor, or simply involved in refrigeration decision-making, this episode delivers real-world insight grounded in experience—not hype. Getting to Know Ryan Reardon

Reciprocating compressors are the most widely used compressor type in refrigeration history and remain common today, especially in residential, commercial, and small industrial systems. Their straightforward mechanical design and proven reliability make them an essential technology for anyone entering the refrigeration industry to understand. Understanding Reciprocating Compressors A reciprocating compressor operates on a principle similar to early steam engines and automobil

OSHA has finalized updates to its Walking-Working Surfaces and Fall Protection standards that affect how fixed ladders over 24 feet are protected in the general industry. For ammonia refrigeration facilities, the most common impact is not a single piece of equipment, but fixed ladders that provide access to rooftops where ammonia piping, Emergency ventilation fans, and sometimes evaporative condensers, are located. When the Rule Applies The updated OSHA requirements apply to

As the industrial refrigeration industry continues to evolve, so do the standards that govern safe system operation and emergency response. One question that continues to surface among facility owners, engineers, and contractors is whether Field Test Pressure  must be included on a machinery room placard. Recent updates to IIAR standards have brought clarity to this topic—and also corrected common misconceptions. At Macha PSM, our engineering team frequently receives requests

At Macha PSM, we believe that strong safety programs begin with strong training. One of the most valuable educational opportunities available through our PSM Academy platform is the Ammonia Awareness Training | Course AA101 —a course specifically built for individuals who work in, around, or in support of ammonia refrigeration systems. While this training has been part of our curriculum, many facility teams may not realize just how impactful it can be for strengthening safety

Ammonia refrigeration facilities under 10,000 lbs often assume they’re “not regulated.” because they fall below the formal PSM/RMP thresholds. But under the General Duty Clause (GDC), the EPA still expects these facilities to identify hazards, maintain a safe system, and prevent accidental releases. While GDC sites are less likely to receive random “lottery” inspections, they will be thoroughly inspected if a release occurs. If you have onsite or offsite consequences, your fa

As the January 1 federal requirement approaches, ammonia refrigeration facilities are working to complete the required Minimum System Safety Evaluations (MSSEs) as part of their overall safety and compliance programs. MSSEs provide a structured approach for evaluating the equipment, components, and systems that are essential to maintaining safe ammonia refrigeration operations. An MSSE covers a wide range of system elements, including vessels, piping, valves, compressors, con

An ammonia refrigeration system operates in two main sections, the high side and the low side. Understanding where one begins and where one ends is key to understanding P&IDs, troubleshooting, and maintaining the system. The primary difference between the two sides is energy and pressure. The high side contains ammonia at higher pressure and higher temperature, as the name suggests, while the low side operates at lower pressure and temperature. The High Side The high side sta

As the saying goes, hindsight is 20/20.  Very often, when an ammonia release occurs, we find that the incident is not addressed in our “what-if” PHA studies.   We perform our incident investigation and realize that the root cause of the release was there all along and was something that could (or should) have been easy to foresee.  But why was it not so obvious when we were conducting our PHA? What did we miss?  Why do we not see the obvious? The following are some tips and s

Last week, our team at Macha PSM had the privilege of attending the 2025 RETA Conference — one of the most energizing and informative events in the ammonia refrigeration and process safety community. It’s always inspiring to gather with professionals who share the same goal we do: keeping people safe, facilities efficient, and programs strong. From the moment we arrived, it was clear that this year’s conference was all about connection and learning from one another, exchangin

When most people think about Process Safety Management, the first things that come to mind are inspections, training, and compliance deadlines. But one of the biggest and most overlooked challenges is poor documentation. Missing or outdated records may seem like a minor issue, but over time, they can lead to significant problems, including delays, audit findings, and unnecessary expenses. 1. The Real Cost of Missing Information In ammonia refrigeration and other industrial sy