Newsline / News

ASHRAE Proposed 62.1 Alternative

October 31, 2011
KEYWORDS ASHRAE / standards
/ Print / Reprints /
ShareMore
/ Text Size+
ATLANTA — Public comment is being sought on the proposed allowance of an additional default value to the ventilation rate procedure in ASHRAE’s indoor air quality standard.

ANSI/ASHRAE Standard 62.1-2010, Ventilation for Acceptable Indoor Air Quality, sets minimum ventilation rates and other requirements for commercial and institutional buildings. The ventilation rate procedure provides a prescriptive method for determining minimum ventilation requirements. It accounts for pollutant sources from both the building and its occupants, and allows the designer to account for the efficiency of different ventilation systems when delivering outdoor air to the breathing zone.

Some users of Standard 62.1 believe that the ventilation rate procedure is “too complicated,” according to Standard 62.1 chair Roger Hedrick. “While the 62.1 committee disagrees with this in most cases — the basics of the VRP are quite straightforward — the committee agrees that application of the multiple-zone recirculating system equations described in Section 6.2.5 and Appendix A can be complex.”

Proposed addendum f provides an additional default value for Vpz.

“Difficulty determining an appropriate value for Vpz seems to be a frequent issue with users of the multiple space equations,” he said. “The committee decided that supplying a default value would simplify application. However, the default value is necessarily conservative. In a large number of applications, determining the ‘lowest zone primary airflow value expected at the design condition analyzed’ will result in a value for Vpz that is higher than the default, resulting in a reduced outdoor air intake requirement.”

Addendum h: Table 6.1 includes ventilation rates for “Sports arena (play area)” and “Gym, stadium (play area).” Both space types have ventilation rates based on floor area only, with a per person rate of zero.

One concern about allowing CO2-based demand controlled ventilation in these spaces is that the volume per person in these spaces is typically large, which means that CO2 concentration changes will have longer than usual lag times behind occupancy changes, he noted.

Addendum g: Currently users are directed that, for space types that are not listed in Table 6-1, they should select the space type from the table that is most similar to the space being designed. However, some space types are actually ventilated using the exhaust ventilation requirements of Section 6.5 and Table 6-4. This proposed addendum adds language directing the user to select the space type that is most similar to the space in question from either Table 6-1 or 6-4, and to design the ventilation for the space according to the Section 6.2 or 6.5, as appropriate.

For more information, visit www.ashrae.org/publicreviews.

Publication date: 10/31/2011

Did you enjoy this article? Click here to subscribe to The NEWS Magazine

You must login or register in order to post a comment.

Multimedia

Videos

Image Galleries

2014 MCAA Annual Convention

Scenes from the 2014 MCAA Annual Convention in Scottsdale, Ariz.

Podcasts

NEWSmakers: Julian Scadden

Training is an ongoing process. Julian will discuss how you can generate maximum return on time and energy invested training by following a three part process. Listen to this podcast to get expert tips on training, tracking and follow up. 

More Podcasts

ACHRNEWS

NEWS 04-21-14 cover

2014 April 21

Check out the weekly edition of The NEWS today!

Table Of Contents Subscribe

SERVICE CALLS POLL

Which statement on service calls best applies to your business?
View Results Poll Archive

HVACR INDUSTRY STORE

plumbing-hvac.gif
2014 National Plumbing & HVAC Estimator

Every plumbing and HVAC estimator can use the cost estimates in this practical manual!

More Products

Clear Seas Research

 

Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.

DON'T MISS A THING

Magazine image
 
Register today for complete access to ACHRNews.com. Get full access to the latest features, Extra Edition, and more.

STAY CONNECTED

facebook icontwitter iconyoutube iconLinkedIn i con