The Associated Air Balance Council (AABC) has published the eighth edition of its National Standards for Total System Balance, updating industry guidance for testing, adjusting and balancing (TAB) HVAC systems for the first time since 2016.
The American National Standards Institute (ANSI)-approved manual establishes minimum standards for total system balance, outlines TAB agency responsibilities and provides procedures intended to help design professionals achieve building system design intent.
“It's important to keep updating the standards because the industry is changing,” says Gaylon Richardson, AABC Standards Committee chairman and representative of Engineered Air Balance Co. Inc., in a press release shared with FacilitiesNet.
The eighth edition includes revisions to TAB reporting requirements, instrumentation and calibration standards, measurement tolerances and Pitot tube traverse procedures. It also adds guidance on fan laws, fan system equations and total leakage recommendations for air leakage testing.
Other updates address testing procedures for constant- and variable-volume systems, energy recovery and temperature control systems, cooling towers, boiler plants, laboratories, kitchens and smoke control systems. The manual also includes new information on air flow-limiting devices (AFLDs) and pressure-independent control valves (PICVs).
The commissioning chapter has been rewritten to provide updated information on HVAC commissioning and commissioning plans. An entirely new chapter expands coverage of underfloor air distribution systems.
Like the seventh edition, the latest version received approval from ANSI. According to AABC, the designation indicates that the standards development process meets ANSI requirements for openness, balance, consensus and due process.
For facility managers, the updated guidance provides a reference for understanding TAB procedures and requirements when verifying HVAC system performance. Proper testing and balancing can help determine whether systems operate as intended and deliver the airflow and other conditions established during design.
The eighth edition of the National Standards for Total System Balance is available through AABC's website.
Jeff Wardon, Jr., is the assistant editor for the facilities market. With more than three years of experience, he covers topics including technology, wellness, sustainability and emerging industry trends. Connect with him on LinkedIn.
