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IIAR 9 and the MSSE Requirement Explained: The Nuts and Bolts Of TheCompliance Obligation By January 1, 2026 | Blog 108
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

Gene Hummel
Jan 215 min read


Understanding Refrigeration Compressors — Part 2 of 3 - Rotary Screw Compressors | Blog No. 107
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

Payton Lemons
Jan 132 min read


Is Ag Ammonia Subject to PSM? | Blog No. 106
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 This belief often comes from partial or outdated interpretations of OSHA and EPA exemptions.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

Eli Macha, Founder & Industry Advisor
Jan 64 min read


The Cold Truth: Episode 1 Recap | A Candid Conversation on Industrial Refrigeration with Ryan Reardon | Blog No. 105
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

Payton Lemons
Dec 30, 20253 min read


Understanding Refrigeration Compressors — Part 1 of 3 - Reciprocating Compressors | Blog No. 104
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

Harrison Stanton
Dec 23, 20252 min read


OSHA Is Phasing Out Ladder Cages— What Ammonia Refrigeration Facilities Need to Know | Blog No. 103
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

Eli Macha, Founder & Industry Advisor
Dec 16, 20253 min read


Understanding What Belongs on Your Ammonia Refrigeration Machinery Room Placard Under the Latest IIAR Standards | Blog No. 102
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

Michael Amaya-Daniel, Process Safety Engineer
Dec 9, 20253 min read


Highlighting a Powerful Training Opportunity: Ammonia Awareness Through PSM Academy | Blog No. 101
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

Payton Lemons
Dec 2, 20253 min read


What the EPA Actually Expects of the General Duty Clause Ammonia Refrigeration Facility | Blog No.100
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

Eli Macha, Founder & Industry Advisor
Nov 25, 20253 min read


Meeting the January 1 Federal MSSE Deadline: What Facilities Need to Know | Blog No. 99
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

Payton Lemons
Nov 18, 20252 min read


Understanding the High Side and Low Side of an Ammonia System | Blog No. 98
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

Michael Amaya-Daniel, Process Safety Engineer
Nov 11, 20252 min read


Polish your PHA crystal ball | Blog No. 97
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
Keith Tyson, Senior Advisor
Nov 4, 20253 min read


Reflections from RETA 2025: Growing, Learning, and Leading Together | Blog No. 96
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

Payton Lemons
Oct 28, 20253 min read


The Hidden Costs of Poor Documentation in PSM Programs | Blog No. 95
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

Payton Lemons
Oct 21, 20253 min read


Post-Weld Heat Treatment of Pressure Vessels | Blog No. 94
In this article, I will explain the basic principles of Postweld Heat Treatment (PWHT), why it is used in the fabrication of pressure vessels, and how to use this information in pressure vessel inspections. The rules for PWHT are found in the ASME pressure vessel code, and I caution you that this article is basic information and in no way comprehensive . If you have a question about a particular vessel, seek advice from the original manufacturer or a repair/alteration organ
Keith Tyson, Senior Advisor
Oct 14, 20254 min read


Reflections on the CSB Report and What It Means for the Future of Ammonia Safety | Blog No. 95
Last week, we shared a breakdown of the U.S. Chemical Safety Board’s (CSB) final report on the hazardous ammonia release at Cuisine...

Harley Stines
Oct 7, 20253 min read


Breaking Down the CSB’s Findings on the Cuisine Solutions Ammonia Release | Blog No. 94
The Chemical Safety Board (CSB) recently released its final report on the hazardous ammonia release at Cuisine Solutions, a food...

Michael Amaya-Daniel, Process Safety Engineer
Sep 30, 20253 min read


Early Lessons from My First Weeks in the Field | Blog No. 93
Graduating in May 2025, I found myself wondering what industry my first engineering job would be in and whether I would even enjoy it...

Harley Stines
Sep 23, 20252 min read


Keeping Ammonia Refrigeration Programs Efficient: Lessons from Operations | Blog No. 92
At Macha PSM, we work with facilities across the country to help them manage process safety for ammonia refrigeration systems. While much...

Payton Lemons
Sep 16, 20253 min read


What Is a Site Map and Why Does It Matter? | Blog No. 91
A site map is a scaled drawing that shows the layout of a facility. It includes buildings, process areas, storage locations, and access...

Michael Amaya-Daniel, Process Safety Engineer
Sep 9, 20251 min read
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