Making Sense of LEED's New Formaldehyde Ruling
By Brent Ehrlich
Composite wood products made with added urea formaldehyde (UF) are one of the few products that LEED has consistently banned under its longstanding IEQc4.4: Low-Emitting Materials credit. However, LEED Interpretation #10250, issued January 1, 2013, and applicable to all LEED projects, now allows for the use of urea in combination with melamine formaldehyde (MF) in certain circumstances. Are these rules in conflict?
According to Sara Cederberg, a LEED manager at the U.S. Green Building Council (USGBC), the interpretation was meant to clarify longstanding questions about the use of MF resins. Currently, products that use MF resins without any urea are allowed, per the original credit language. However, many MF-containing products have a urea component. The interpretation addresses those products as follows:
• Urea, when used as part of a melamine-urea-formaldehyde (MUF) resin, is allowed as long as the composite wood product meets California Air Resource Board (CARB) Airborne Toxic Control Measure (ATCM) 93120 requirements for ultra-low-emitting formaldehyde resins (ULEF), or 0.05 parts per million—requirements that are quite strict.
• Melamine-formaldehyde resins that use urea as a “scavenger” are not allowed, even with ULEF testing showing that they meet the same emissions standard.
“The language is confusing,” says Andre Verville, research and technical director at Uniboard, maker of ULEF melamine particleboard and other composite wood products. The interpretation states that UF acting as a scavenger is not allowed, but urea formaldehyde is not used as a scavenger, per se. Urea itself “scavenges” leftover free formaldehyde from the MF reaction and converts it into another form, which should actually reduce formaldehyde emissions from the product, he explained, when compared with MF resins that don’t use urea scavengers. Verville said that pure MF products could have up to three times the emissions of those using the scavenger.
The chemistry of these resins is complicated, and Cederberg said stakeholders’ concerns that formaldehyde could be released over time from products using urea as a scavenger—particularly in hot, humid climates—informed the current interpretation. USGBC is reviewing the policy, however, and Cederberg said that the interpretation could be updated in April 2013.
Overall, it makes sense for USGBC to evolve in its position on urea formaldehyde, because rather than basing its rules on the complexities of chemistry, it could move to a performance-based policy based on actual emissions, using standards that didn’t exist when it originally adopted the no-UF rule. That’s the direction USGBC is taking with LEED v4; draft language there calls for low formaldehyde emissions, as measured by CARB ULEF standards. In the meantime, however, this change to LEED 2009 adds confusion to what has been a fairly black-and-white, easily understood requirement.