Mission Critical Facilities, Data Centers, Technology Spaces and Electronic Equipment
ASHRAE Technical Committee 9.9


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TC0909 Houston Agenda 20180624

Upcoming TC Meetings

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Location: Houston, TX  
Sunday, 6/24/2018  Room
5:00 PM - 7:00 PM - Programs, Handbook and Research

George R. Brown Convention Center,
3rd floor, 370 ABDE

Monday, 6/25/2018  
2:15 PM - 7:30 PM - Main Committee

George R. Brown Convention Center,
3rd floor, 371 AB

TC 9.9 sponsored seminars, conference paper session, data center related topics, etc. will be posted for each conference in the Meetings section of this website.


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Committee Chair

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Jason Matteson TC0909@ashrae.net

Committee Scope

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TC 9.9 is concerned with all aspects of mission critical facilities, data centers, technology spaces, and electronic equipment/systems.


Upcoming Society Conferences

2019 Winter Conference
January 12–16, 2019
Atlanta, GA


Conference Badges

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Latest TC Activities

If you would like to get involved in this TC's activities you can contact the appropriate Point of Contact in the TC 9.9 Work Items listing, attend the biannual meetings, or contact our committee chair at tc0909@ashrae.net.


August 27

To Members and Parties Interested in SSPC 90.4, the following addenda to ANSI/ASHRAE Standard 90.4-2016, Energy Standard for Data Centers will be out for a 30 day public review:

30 day Public Review
August 25th, 2017 – September 24th, 2017

1st Public Review of BSR/ASHRAE Addendum to ANSI/ASHRAE Standard 90.4-2016, Energy Standard for Data Centers

This addendum deletes the definition of alteration from Section 3 of Standard 90.4, thereby reverting to the definition of alteration in Standard 90.1 (which is reproduced in Standard 90.4 Annex 1).

1st Public Review of BSR/ASHRAE Addendum to ANSI/ASHRAE Standard 90.4-2016, Energy Standard for Data Centers

This addendum clarifies the exception in Section that addresses the case where existing HVAC systems and equipment serve an addition, and adds parallel criteria to Section 8.1.3 for electrical equipment.


June 23rd

March 01, 2017 Conference Paper Abstracts, Technical Papers and Paper Session Requests Due
March 27, 2017 Conference Paper Abstract Accept/Reject Notifications
June 02, 2017 Website Opens for Seminar, Forum, Debate, Panel and Workshop Proposals
July 07, 2017 Final Conference Papers Submitted for Review (Includes Bio, Learning Objectives and Methods of Assessment); Request for Conference Paper Sessions Due
July 24, 2017 Conference Paper accept/reject notifications
August 01, 2017 Seminar, Forum, Workshop and Paper Proposals Due
August 07, 2017 Revised Conference Papers/Final Technical Papers Due
August 21, 2017 Conference and Technical Paper Final Accept/Reject Notifications
September 06, 2017 Seminar, Forum, Workshop Accept/Reject Notifications
December 01, 2017 Upload of PPTs Begin
January 08, 2018 All PPTs Due Online
January 17, 2018 Final Day for Commercialism Revision Upload prior to on-site
January 20, 2018 Speaker's Lounge Opens

Past presentations given at the ASHRAE annual and winter meetings are now available.  They can be found on the Documents page under the 'Other Publications' section.


November 6th

Hello TC 9.9 Members,

You are invited to attend this TC 9.9 online meeting to hear the latest update from TC 9.9 members. 
Conference information:   9AM PST; 12PM EST  Dial-in Number: (712) 770-4010  Access code : 800393 #

International callers can find an in-country number dial-in number in this document.  This is only a phone conference with no online presentations.  If you have a pressing question that you would like answered, please let the committee chair (tc0909@ashrae.net) know ahead of time. 


  1. Introduction/Website Update
  2. Las Vegas ASHRAE Meeting Information
  3. Programs Update  
  4. Handbook Status
  5. Research Update
  6. Standards updates for ASHRAE 90.1 and ASHRAE 90.4
  7. ITE Subcommittee report


September 25th
The new ASHRAE Standard 90.4-2016, Energy Standard for Data Centers, establishes the minimum energy efficiency requirements of data centers for design and construction and for creation of a plan for operation and maintenance, and for utilization of on-site or off-site renewable energy resources.  Through publication of its Datacom series, ASHRAE has emerged as a leader in the data center field.  Standard 90.4 draws upon the collective expertise of the industry to promote stable and sustainable data centers.

Standard 90.4 is a performance-based design standard that offers the design components for mechanical load (MLC) and electrical loss (ELC). Calculations of the MLC and ELC are made and then compared to the maximum allowable values shown in the standard based on climate zones. Compliance with Standard 90.4 is achieved when the calculated values do not exceed the values contained in the standard. An alternative compliance path is provided that allows tradeoffs between the MLC and ELC.


June 18th
The tentative agenda for the Sunday and Monday meetings has been set.  Topics and order are subject to change as we approach the meetings.  Please plan to attend.  The agenda can be found here.


The paper, “Data Center Power Equipment Thermal Guidelines and Best Practices” contains an overview of data center power distribution and how changes in the data center thermal environment can affect power distribution equipment.  The paper includes recommendations on how to improve power equipment thermal compatibility with IT equipment particularly where power equipment shares the same physical space and air stream as IT equipment.



The 4th ISC Public Review of BSR/ASHRAE Standard 90.4 is now open.  The public review runs from April 29, 2016 to May 29, 2016.  This ISC draft revises the definition of incoming electrical service point, corrects equations in Section, revises Tables and, adds verification of equipment efficiencies to Sections 6 and 8, corrects equations, revises Section 11.3 and updates references in Section 12.  The link to the standard can be found here: https://osr.ashrae.org/default.aspx.



As committed at the Orlando meeting, the overview presentation for TC 9.9 has been updated and is now available on this site.  This overview can be used by members to understand what TC 9.9 does and the resources available from TC 9.9.  Please consider this as ASHRAE’s material and always follow appropriate use considerations.



An error was discovered in the latest edition of the ‘Thermal Guidelines’ book. ASHRAE has produced the attached errata and it can be downloaded by everyone from the following webpage (You do not have to have purchased the book to download the errata page.)


 Please check out this errata which addresses the humidity levels for all ASHRAE air classes.  Anyone can print out the material and insert it into their copy of the Thermal Guidelines book.  The PDF will not be updated until the next reprint which may take some time.


TC 9.9 Approved Definitions for Data Centers, ITE, and ITE Enclosures

TC 9.9 is recognized as a leader in driving the data center environmental knowledge and best practices in the industry. At the ASHRAE Annual Meeting in Orlando, TC 9.9 discussed one area where we must help to align our industry. Previously TC 9.9 has not provided definitions for ITE and locations where it is housed. It is essential that we do this to meet our mission "To be recognized by ALL areas of the datacom industry as the unbiased engineering leader in HVAC and an effective provider of technical information for the datacom industry."

It is important for data centers to be excluded from codes written for human occupancy. Even an IT server rack does NOT fit human occupancy codes. Racks that belong in human occupancy codes are ones supporting building services such as fire, security, HVAC, audio / video, etc. These racks are typically far less than 2 KW per rack. There might be occasional exceptions but those are minor compared to human occupancy codes requiring economizers on 2 KW IT server racks.

TC 9.9 has approved the following definitions for use by those needing to quantify data center related terms. Please consider them as the position of TC 9.9 as we move forward in developing standards, codes and general communications for our industry.

1) Data Center: A room or building, or portions thereof, with one or more ITE enclosures greater than 2 KW.
2) Information Technology Equipment (ITE): Computers, data storage, servers and network / communication equipment.
3) ITE Enclosure: A rack, cabinet, or chassis that is designed to mount ITE.


New Whitepapers

Data Center Storage Equipment - Thermal Guidelines, Issues and Best Practices

This paper defines thermal guidelines best practices for storage equipment. The intended audience is both storage hardware designers and storage equipment users. The thermal guidelines were written by a team of storage subject matter experts from many different companies and the recommendations are industry-wide best practices which are agnostic of the point of view of any one company.

Clarification to ASHRAE Thermal Guidelines

There has been some confusion of ASHRAE's definition in the Thermal Guideline Datacom Book of the Temperature Rate of Change specified in the table for Equipment Environmental Specifications for Air Cooling. This addendum helps describe in detail examples of air inlet that are either non-compliant or compliant to ASHRAE's temperature rate of change requirements for data centers.

ASHRAE Bookstore

A bulk quantity discount for the Datacom Series Products applies to purchases of 10 or more copies of one title or any combination of titles.

TC 9.9 Datacom Books

Quantity discounts are available for purchases of 10 or more books (mix & match).  Please contact the Manager of Inventory and Subscriptions for instructions on receiving your discount.

Visit the ASHRAE Bookstore Now!