Anti-Rust vs flat primer

You have the right idea…almost. The Green Seal GC-03-1997 definition of “Anti-Corrosive Paint” is extraordinarily vague, so judging which products qualify is tricky. Instead, I use CARB’s criteria for “Rust Preventative Coating,” which require labeling “For Metal Substrates Only” with application only “direct-to-metal” or to “rusty, previously coated surfaces.” CARB also excludes coatings that require primer and those intended for non-metallic substrates. However, I would not expect MSDS to include such labeling. MSDS provide safe handling and emergency instructions. For substrate and application requirements and for gloss classifications, I would look to manufacturers’ technical data sheets. Finally, if I classify a coating as a primer, the VOC limit is now 200g/L, according to an October 2013 Addendum: http://www.usgbc.org/resources/ieqc42-table-1-applicable-voc-limits & http://www.usgbc.org/leed-interpretations?keys=100001805.

So even though my LEEDonline template shows it as: Interior Flat Paint, Coating, Or Primer =50 Sealers & Undercoaters =200 I should be able to claim a primer under the 200 VOC Limit?

Patricia—The NC-2009 IEQc4.2 v06 form has been updated to include the 200g/L “Primers, sealers and undercoaters” category. You appear to be using one of the older LEEDonline forms that lists primers with “interior non-flat.” If you continue to use the old form, you should be able to enter primers with “Sealers and undercoaters.” To be safe, you might want to cite the addendum in a “Special Circumstances” narrative. See http://www.usgbc.org/content/ad-100001805.

Thanks Jon!!

Jon, one more question. What if it was a flat paint used as a primer? I.e. it doesn't have primer in the product name.

Is this a flat paint that complies with the 50g/L VOC limit for interior flat topcoats? If so, you can list it either as a flat or as a primer/sealer/undercoater, but I would probably list it as a flat. (The addendum notes, “General purpose primers for wall and ceiling paint are widely available at lower VOC concentrations than the specified limit.”) If the flat primer has more than 50g/L, you may need to check the label (or technical data from the paint manufacturer). If the label lists the product as a “topcoat,” you may have trouble claiming it as a primer, but if the label (or product data) says primer, you may be okay claiming the product as a primer with a 200g/L VOC limit. Rationale: SCAQMD-1113 states, “If anywhere on the container of any coating listed in the Table of Standards, on any sticker or label affixed thereto, or in any sales or advertising literature, any representation is made that the coating may be used as, or is suitable for use as, a coating for which a lower VOC standard is specified in the table…, then the lowest VOC standard shall apply.” Therefore, if the label says both “topcoat” and “primer,” the lower, “topcoat” VOC limit applies, but if the product is recommended only as a “primer,” it is one.