Codes and standards drive trends, changes in data center design
Several codes and standards are pushing the engineered systems in data centers in different directions
- Bill Kosik, PE, CEM, BEMP, Senior Energy Engineer, DNV, Oak Brook, Illinois
- Matt Koukl, DCEP, Principal, Market Leader Mission Critical, Affiliated Engineers Inc., Madison, Wisconsin
- Kenneth Kutsmeda, PE, LEED AP, Global Technology Leader – Mission Critical, Jacobs, Philadelphia
- Ben Olejniczak, PE, Senior Project Mechanical Engineer, Environmental Systems Design Inc., Chicago
- Brian Rener, PE, LEED AP, Mission Critical Leader, Smith Group, Chicago
- Jonathan Sajdak, PE, Senior Associate/Fire Protection Engineer, Page, Houston
What are some best practices to ensure that such buildings meet and exceed codes and standards?
Jonathan Sajdak: At the beginning of each project, it is key to identify all applicable codes and standards. Coordination with the authority having jurisdiction during the early stages of the design can also be very helpful. During these conversations, the applicable codes and standards can be reviewed and a high-level overview of the design can take place to ensure both parties are in agreement with the requirements. One of the biggest challenges that can pop-up on a project is when an owner requirement, insurer requirement or local amendment was overlooked as the design stage nears completion. It may be difficult to implement the required system or design feature due of the lack of available space in the facility or its impact on other disciplines.
One additional clarification to highlight is that in most jurisdictions, clean agent systems cannot be used in lieu of automatic sprinkler systems. Clean agent systems are not intended to be used as a replacement for sprinkler systems, but instead be used in addition to as an extra layer of protection with the goal of rapid suppression/containment of the fire and mitigating damage to property and assets.
Ben Olejniczak: One of the most important best practices that I could recommend is to simply stay on top of the latest revisions of all the documentation that may influence your design. It sounds simple, but it actually requires a fair amount of time investment to understand and keep track of subtle changes that occur in each revision. Also, it’s very important to stay on top of the latest technology that equipment vendors are working on to ensure they are keeping up with the changes as well. With all the changes happening within codes and at the legislative level, sometimes it is difficult for all parties to stay current.
How has ASHRAE Standard 90.4-2019: Energy Standard for Data Centers affected your work?
Bill Kosik: I think one of the main ways ASHRAE 90.4 has affected my work is by the standardization of certain design elements. An example of this: the code has instructions on how to calculate the electrical losses based on the reliability of the electrical system. Seemingly minor, the electrical losses could total up to nearly what it takes to power the fans. This also is conducive to modeling what-if scenarios to calculate the power loss and associated air conditioning energy consumption.
How are codes, standards or guidelines for energy efficiency impacting the design of data centers?
Matt Koukl: Data centers are unique compared to traditional building facilities that accommodate creature comforts while balancing the facility’s energy use. With high sensible loads and computing power involved, data centers have a significantly higher base load and energy use intensity than most other facility types. As designers of these facilities, we must ensure the infrastructure and heat rejection systems operate at the highest levels of energy and water efficiency. A common approach to achieving the code energy requirements is by evaluating the supply water temperatures to gain the highest number of economizing hours to reduce the annual energy use of mechanical cooling systems.
Ben Olejniczak: As codes, standards and guidelines become more restrictive, it will require the designer to think critically about their approach to designing a data center. Enhanced complexity generally accompanies systems that integrate economization/free cooling from a controls perspective. To be clear, this is not a downside to the design — it just requires deeper thought and analysis. Systems that may have been assumed as the status quo may no longer be feasible and alternate solutions may be required to be investigated.
What new or updated code, standard, guideline organization or association do you feel will change the way such projects are designed, bid out or built?
Kenneth Kutsmeda: Two new codes that engineers should be aware of are International Fire Code – Section 1206 Electrical Energy Storage Systems and NFPA 855: Standard for the Installation of Stationary Energy Storage Systems. Both codes contain important new requirements (location, separation, quantities, etc.) that relate to the installation of battery systems in particular lithium-ion batteries. UL 9540A is a testing standard that can provide compliance to the new IFC and NFPA code regulations, but it must be approved by the local AHJ.
What are some of the biggest challenges when considering code compliance and designing or working with existing buildings?
Brian Rener: On the electrical side, it is critical to understand exiting fault and arc flash levels and models in order to properly specific rated and safe additions and modifications.
Jonathan Sajdak: With existing buildings, one challenge we have seen is the use of existing sprinkler piping in facilities that are planned to be converted into data centers. When an existing building and system is inherited, attention should be given to the condition of the existing piping (both internal and external) and determining whether or not it needs to be replaced. Corrosion mitigation is key in data centers and the integrity of the sprinkler pipe is vital. Corrosion is one of the leading causes of systems leaks, which could result in unwanted discharge of sprinkler systems in equipment areas. Supplementary systems or features to help with this can include nitrogen generation, automatic air venting and pipe thickness/material selection.
Kenneth Kutsmeda: The biggest challenge I faced with code compliance is the interpretation of the code by different jurisdictions. Codes can be interpreted differently based on the experience and expertise of the person reviewing the code. Early in my career a challenge I faced repeatedly with AHJ was the elimination of emergency power off, or EPO, system for the data center. EPO systems were potential points of failure that could take down the data center, so most clients wanted them eliminated. Data center designs were adjusted so that they no longer governed by NFPA 70: National Electrical Code Article 645 and therefore no longer required an EPO system. Most of the AHJs had experience with the requirements of NEC 645 IT equipment that required EPO buttons in data centers. Convincing AHJ that the data center was no longer governed by NEC 645 was a big challenge.