Machinery Room Ventilation Analysis Tool
The idea and the majority of the work for developing a ventilation analysis tool to determine if ventilation systems met the codes and standards at the time the ventilation system was built was provided by Ron Worley. More than 2000 hours was put into research to find the applicable codes and standards and the development of the tool. Doug Reindl, with the IRC, collaborated and provided expertise on this project and also led the peer review with eight registered professional engineers.
Ventilation is an important safety system for machinery rooms that house industrial refrigeration systems. This spreadsheet tool is offered to IIAR members to help analyze existing machinery room conditions and the codes and standards to which they were designed. It can be useful for providing sufficient information to serve as the basis for documenting the ventilation systems for regulatory purposes. Key aspects of the ventilation design requirements of IIAR 9-2020 and IIAR 2-2021are summarized later in the document.
For the design of new ventilation systems, users are encouraged to refer to the latest edition of IIAR -2.
This ventilation analysis tool includes anhydrous ammonia as one of the refrigerant choices. Some facilities using anhydrous ammonia may be subject to regulatory requirements such as OSHA’s Process Safety Management (PSM) standard [29 CFR 1910.119] as well as EPA’s Risk Management Program [40 CFR Part 68]. For those covered processes, employers/operators are required to document the design and design basis for their machinery room ventilation systems [see 1910.119(d)(3)(i)(E) and 40 CFR 68.65(d)(1)(v)]. The intent of this tool is to provide sufficient information to serve as the basis for documenting the ventilation systems for machinery rooms housing such covered processes.
Included in the latter sections of this spreadsheet is a summary of the key ventilation requirements given in IIAR 2 (provided with permission from IIAR). The specific requirements for machinery room ventilation in other codes and standards can be obtained by contacting the relevant code/standard developer. For the IMC, contact the International Code Council (www.iccsafe.org). For , Standard 15, contact ASHRAE (www.ashrae.org). For the UMC and CMC, contact IAPMO (www.iapmo.org). For Canadian Standards Association (CSA) B52, contact CSA (www.csa.ca).
Collectively, these documents establish what OSHA refers to as industry Recognized as Generally Accepted Good Engineering Practices (RAGAGEP). It is important to keep in mind that codes and standards are not static but frequently change. In many cases, changes to codes and standards do not retroactively apply the updated or new requirements to existing systems. Although an existing system may not be subject to these revised or new requirements, it is important for owners and design professionals to consider whether implementing the revised requirements to an existing system will materially enhance safety. In that case, a business decision may prompt the upgrade. Finally, codes and standards will dictate that revised requirements must be implemented when substantive changes are made to a machinery room or system.
The summaries included in this spreadsheet are NOT necessarily all inclusive with the controls and other design requirements related to machinery room ventilation systems (e.g. discharge locations, etc.). This spreadsheet is focused on the calculations related to both non-emergency and emergency ventilation requirements for machinery rooms using ammonia and other refrigerants.
This analysis tool is provided as a courtesy by Ron Worley and Doug Reindl. Questions should be referred to Ron and/or Doug.
Please be sure to read the introduction and disclaimers on the first tab of the tool.
Users of this tool must carefully review the information provided in the “DISCLAIMER” tab of this tool prior to its use.