Formaldehyde-free insulation revisited.(Letters)(Letter to the Editor)

I read with interest Tim Grether's letter (see Dec. 2004, page 31) concerning my recent article, "The Real Value of Insulation" (see Sept. 2004, page 32). Mr. Grether makes several statements that need to be clarified and given additional context.

Manufacturers that cannot make a claim of "non-detect" for formaldehyde acquire and promote indoor air quality eco-labels such as Greenguard. Some of the emissions standards used by these certifications have been called into question by organizations such as the California Air Resources Board (CARB). In response to comments on