The First Facility Management Blog

ASHRAE is currently accepting public input on more than 35 proposed addenda to standards as well as a proposal to withdraw Standard 52.1. Addendum to various standards, including 15 (refrigerate safety), 34 (classification of refrigerants), 55 (thermal comfort), 90.1 (energy efficiency), 62.1 (ventilation), 62.2 (residential ventilation), and 135 (BACnet) are open for review, as are seven standards and one guideline. Compete information can be found at www.ashrae.org/publicreviews.
 Among them is the proposed withdrawal of ASHRAE Standard 52.1-1992, Gravimetric and Dust Spot Procedures for Testing Air Cleaning Devices Used in General Ventilation for Removing Particulate Matter.

The most important features of this standard, dust holding capacity and arrestance, have been incorporated into Standard 52.2-2008, Method of Testing General Ventilation Air Cleaning Devices for Removal Efficiency by Particle Size. The only unique features remaining in Standard 52.1 are the dust spot efficiency tests—now replaced particle size efficiency tests in 52.2—and a renewable filter test not used by the industry for decades, according to Monroe Britt, committee chair.


Among the proposed addenda to Standard 90.1 is addenddum ap, which would modify the requirements for demand control ventilation; adding the demand controlled ventilation requirements to the simplified approach in order to keep the stringency of this path the same as the mandatory plus prescriptive path of compliance. Also proposed is a change to addendum af to modify energy savings requirements to recognized varied piping material pressure drops.


Six proposed addenda to Standard 62.1 are open for comment, including a proposal regarding outdoor air cleaning. Addendum 62.1c adds significant air cleaning requirements in many locations within the United States. Regarding particulate matter 2.5 micrometers and smaller, for buildings in those U.S. locations established as non-attainment for PM2.5 by the U.S. Environmental Protection Agency, 62.1c would require that the ventilation system include particle filters rated at least MERV 11 (installed between the outdoor air intake and the occupied zone). Regarding ozone air cleaning, the proposed addendum would require that the ventilation system include ozone air cleaners rated for at least 40% ozone removal efficiency. 

In late May, the International Code Council approved an ASHRAE proposal to incorporate the prescriptive ventilation rate procedure from ANSI/ASHRAE Standard 62.1-2004, Ventilation for Acceptable Indoor Air Quality, in the International Mechanical Code (IMC). The code establishes minimum regulations adopted and implemented by federal, state and local government agencies for mechanical systems in new buildings. Approval of ASHRAE’s Standard 62.1 ventilation rate calculation procedure marks a milestone for the high-profile mandatory language standard after years of development aimed at code adoption.

“With adoption of the new ventilation rates into building codes, we can expect to see reduced air intake flow in many previously over ventilated buildings,” says Dennis Stanke, chair of the 62.1 committee. “With adoption of the new calculation procedures, we can expect to see improved indoor air quality in many previously under-ventilated multiple-zone systems. Ventilation systems with lower outdoor rates compared to the current code reduce both first costs and energy costs, while system designs that account properly for air distribution within buildings result in better indoor air quality than designs based on over-simplified air distribution assumptions.”

The current ventilation criteria in the IMC are based on ASHRAE Standard 62-1989. Based on 20 years of IAQ research and experience with ventilation system design, ASHRAE introduced an improved version of the standard in 2004 to include the new rates and calculation procedures. This code change makes both the IMC and the 2006 Uniform Mechanical Code consistent with the ASHRAE standard.

“The new ventilation rate procedure requires designers to account for pollutant sources from both the building and its occupants, and to account for the efficiency of different ventilation systems when delivering outdoor air to the breathing zone,” Stanke said.

The new requirements will be included in the 2007 IMC Supplement.