CARB provides special provisions for manufacturers of composite wood products that use no-added formaldehyde (NAF) or ultra-low-emitting formaldehyde resins (ULEF) resins. NAF-based resins are resins formulated with no added formaldehyde as part of the resin cross-linking structure. ULEF resins are formaldehyde-containing resins formulated such that the formaldehyde emissions from composite wood products are consistently below applicable Phase 2 emission standards.
Manufacturers who demonstrate the use of NAF resins can receive an exemption from CARB requirements, and such manufacturers are “CARB exempt.” Manufacturers who use ULEF resins can apply for approval to have their products tested less frequently or for an exemption. There is a list of approved NAF/ULEF mills on the Air Resources Board website.
Source: California Air Resources Board