ASHRAE proposes alternative compliance path for existing buildings

Recognising that the ventilation rate procedure in its Indoor Air Quality standard may be difficult to apply in existing buildings, ASHRAE is proposing an alternative compliance path.

Revealing this in a communiqué ASHRAE elaborated that the proposed addendum b is one of six addenda to ANSI/ASHRAE Standard 62.1-2013, Ventilation for Acceptable Indoor Air Quality is open for public comment from September 5 to October 5.

According to ASHRAE, responding to increasing interest in sustainability in existing buildings, Standard 62.1 is cited frequently as a criterion for evaluating ventilation systems in existing buildings. Some building categories, such as K-12 schools and office buildings, are frequently renovated and often have multiple zone systems that provide HVAC to similar space types.

In light of this, ASHRAE explained that Section 6 (including the ventilation rate procedure) of the standard was developed as a design standard. As such, Section 6 and Normative Appendix A have the complexity to allow for many complex system designs and airflow pathways. The scope of the standard, said ASHRAE,  states in part that “the provisions of this standard are not intended to be applied retroactively when the standard is used as a mandatory regulation or code.”

“For existing buildings, it may be difficult to apply the ventilation rate procedure (VRP), particularly for buildings with multiple-zone recirculating ventilation systems,” Roger Hedrick, Chair of the Standard 62.1 committee, highlighted. “This is because determination of some of the values needed to calculate ventilation rates may be difficult or impossible because required information is not available.”

The proposed addendum b provides an alternative path of compliance that is needed by the marketplace for those situations where information required to determine system performance is unavailable or for smaller facilities with straightforward multiple zone applications, he explained.

ASHRAE added that further details and other addenda open for public comment are available at: www.ashrae.org/publicreviews.