RAGAGEP: Codes, Standards, and Good Engineering Practices (Part 3)

Peter Thomas, P.E. recently wrote a technical paper and presented at the 2017 RETA National Conference on the topic of RAGAGEP: Codes, Standards, and Good Engineering Practices. This is the third in a series of blogs which include excerpts from his technical paper. The previous blogs are available in the following links: Part 1, Part 2.

RAGAGEP Documents

While it is necessary to familiarize with the organizations listed in the previous section, it is of greater importance to be familiar with the documents that they have published, since it is the contents of these documents that are considered RAGAGEP.

IIAR

IIAR publishes standards that are specifically focused on ammonia (and CO₂) refrigeration. As such, it is essential to be familiar with IIAR’s literature which has often been cited as RAGAGEP by EPA and OSHA.  Prior to developing bona fide “standards”, IIAR published a series of “bulletins” that provided “guidelines” on a wide range of ammonia refrigeration topics:

• IIAR Bulletin No. 107 Guidelines for: Suggested Safety and Operating Procedures When Making Ammonia Refrigeration Plant Tie-ins
• IIAR Bulletin No. 108 Guidelines for: Water Contamination in Ammonia Refrigeration Systems
• IIAR Bulletin No. 109 Guidelines for: IIAR Minimum Safety Criteria for a Safe Ammonia Refrigeration System
• IIAR Bulletin No. 110 Guidelines for: Start-up, Inspection and Maintenance of Ammonia Mechanical Refrigerating Systems
• IIAR Bulletin No. 111 Guidelines for: Ammonia Machinery Room Ventilation
• IIAR Bulletin No. 112 Guidelines for: Ammonia Machinery Room Design
• IIAR Bulletin No. 114 Guidelines for: Identification of Ammonia Refrigeration Piping and System Components
• IIAR Bulletin No. 116 Guidelines for: Avoiding Component Failure in Industrial Refrigeration Systems Caked by Abnormal Pressure or Shock
• IIAR Bulletin No. R1 A Guide to: Good Practices for the Operation of an Ammonia Refrigeration System

Note: IIAR Bulletins No. 106, 113, and 115 were never published and the gaps in numbering were likely holding places for planned documents that were never written.

At the time that these bulletins were published, it was not known that these documents would be viewed as RAGAGEP and enforceable by OSHA and EPA. The above-mentioned bulletins do not use “code language” (words such as “shall”, “must”, etc.) and are peppered with vague and optional requirements (words such as “can”, “should”, “may”, etc.). For example, IIAR Bulletin No. 110 §6.4.2 reads as follows [emphasis mine]:

The system should be checked regularly for the presence of non-condensable gases which should be purged as necessary from the receiver(s) and/or condenser(s), preferably into a noncondensable gas remover or purger but alternatively into water. Where an automatic purger is fitted, its correct operation should be monitored. If there is a large accumulation of noncondensable gases the reason should be investigated and the cause should be corrected.

As OSHA/EPA began to use the IIAR bulletins as enforceable RAGAGEP, it became clear that the best way to address the short-comings in the bulletins was to retire them altogether and replace them with standards written in code language. To date, the following standards have been published by IIAR:

• ANSI/IIAR 1 Definitions and Terminology Used in IIAR Standards
• ANSI/IIAR 2 Standard for Safe Design of Closed-Circuit Ammonia Refrigeration Systems
• ANSI/IIAR 3 Ammonia Refrigeration Valves
• ANSI/IIAR 4 Installation of Closed-Circuit Ammonia Mechanical Refrigeration Systems
• ANSI/IIAR 5 Start-up and Commissioning of Closed-Circuit Ammonia Refrigeration Systems
• ANSI/IIAR 7 Developing Operating Procedures for Closed-Circuit Ammonia Mechanical Refrigerating Systems
• ANSI/IIAR 8 Decommissioning of Closed-Circuit Ammonia Mechanical Refrigeration Systems

The language in these standards supersedes the content in Bulletins No. 107, 111, 112, and R1. As such, these bulletins have been “retired” and are no longer available for purchase. As of the date of publication of this paper, two additional standards are in the process of being written or currently subject to public review:

• IIAR 6 Standard for Inspection, Testing, and Maintenance of Safe Closed-Circuit Ammonia Refrigeration Systems
• IIAR 9 Standard for Recognized and Generally Accepted Good Engineering Practice (RAGAGEP) for Existing Closed-Circuit Ammonia Refrigeration Systems

Until IIAR 6 is published, IIAR Bulletins No. 108, 109, 110, and 116 will continue to be published and available for purchase, but upon completion of IIAR’s entire suite of standards, all bulletins will be officially retired. IIAR Bulletin No. 114 is a guideline and its content will likely remain in publication, possibly as part of the IIAR Ammonia Refrigeration Piping Handbook.

It is appropriate to make special emphasis on the importance of IIAR 2. The current version, ANSI/IIAR 2-2014, is the first published “safety standard” to address the design of closed-circuit ammonia refrigeration systems. IIAR 2 was originally published in 1974, but from initial publishing until the current version, was not written as a “safety standard” and therefore, not widely recognized by the larger code community. With the significant changes to the standard that occurred in 2014, the document is now widely recognized by model codes and other standards. A subsequent section of this paper will investigate this topic in greater detail, including examples of IIAR references in code documents.

ASHRAE

ASHRAE publishes numerous standards, but two have had particular impact on the ammonia refrigeration industry for decades:

• ASHRAE 15 Safety Standard for Refrigeration Systems
• ASHRAE 34 Designation and Safety Classification of Refrigerants

ASHRAE 15 has been the foundational safety standard for the larger refrigeration community, both ammonia and synthetic refrigerants. The document was first published in 1978 and has been republished ten times since. Originally, ASHRAE 15 was written to replace American Standard B9 Safety Code for Mechanical Refrigeration, the premier refrigeration standard dating back to 1930.

It is currently proposed that ASHRAE 15 remove ammonia refrigeration from the scope of the document and simply reference IIAR 2 for minimum requirements when ammonia is the refrigerant in a refrigeration system. This is the likely trajectory for this document and when finalized, will result in ASHRAE 15 no longer being considered RAGAGEP for ammonia refrigeration systems.

ASME

ASME standards typically address a wide array of industries. The organization’s flagship standard, Boiler and Pressure Vessel Code, is referenced in a vast array of industries including ammonia refrigeration. A summary of ASME standards that impact the ammonia refrigeration industry include:

• Boiler and Pressure Vessel Code (B&PVC), Section VIII, Division 1 Rules for the Construction of Pressure Vessels
• ASME B31.3 Process Piping
• ASME B31.5 Refrigeration Piping and Heat Transfer Components
• ASME A13.1 Scheme for the Identification of Piping Systems

It is important to emphasize that ASME B31.3 is not applicable to ammonia refrigeration piping. It was included on this list because it is a widely referenced standard and may be cited incorrectly by OSHA or EPA. It is important to familiarize with popular RAGAGEPs to be able to intelligently apply (or not apply) them to a given industry.

ICC

ICC’s model codes are widely adopted throughout the United States. While all of the ICC codes have the potential to impact ammonia refrigeration facilities, the following two documents have chapters / sections which specifically address refrigeration:

• International Fire Code
• International Mechanical Code

IFC Section 606 Mechanical Refrigeration and IMC Chapter 11 Refrigeration are the most important sections of the ICC literature for determining ammonia refrigeration RAGAGEP. In California, the governing fire code, California Fire Code, is a derivative of the International Fire Code.

It is worth highlighting that the 2015 IMC and 2015 IFC both require ammonia refrigeration systems to comply with IIAR 2.

IAPMO

IAPMO’s plumbing and mechanical model codes are less widely adopted than ICC’s codes, but still important. IAPMO’s Uniform Mechanical Code (UMC) is used in several western states, including California which has adopted the California Mechanical Code, a derivative of the UMC. The 2015 UMC requires ammonia refrigeration systems to comply with IIAR 2, IIAR 3, and IIAR 5.

NFPA

NFPA standards have the potential to impact many aspects of ammonia refrigeration facilities, but typically, the following three standards have the most effect:

• NFPA 1 Fire Code
• NFPA 70 National Electric Code
• NFPA 704 Identification of the Hazards of Materials for Emergency Response

ISEA

ISEA standards are less commonly known than some of the previous standards discussed, but ANSI/ISEA Z358.1 Emergency Eyewash and Shower Equipment has had considerable impact on the ammonia refrigeration industry with regard to eyewash and safety shower location. ISEA Z358.1 is a reference document in IIAR 2.