US Environmental Protection Agency

Regulator Responsibility:

The Environmental Protection Agency is the primary federal US agency developing and enforcing regulations to protect the environment. The Clean Air Act (CAA) is the basis of the EPA’s mandate and actions with respect to reducing atmospheric pollution. Its guidelines become the basis for each state to develop and implement their individual State Implementation Plans (SIPs) to come into compliance with, or exceed, the EPA regulations. In addition, local regulators such as South Coast Air Quality Management District (SCAQMD) develop and implement their own regulations that are in harmony with the EPA and in many cases, more restrictive.

Definition of VOCs:

Under the National Ambient Air Quality Standards, the EPA has defined Volatile Organic Compounds as any substance which participates in atmospheric photochemical reactions, i.e. any substance that contributes to the formation of smog. Industrial solvents are the largest single contributor to VOC emissions and so receive close scrutiny.

VOC Content.

To determine the VOC content of a product, the manufacturer must calculate the VOC contribution by weight of each component that is not considered VOC-exempt. The total VOC content must be below the VOC limit for that product, or else it cannot be manufactured or sold in that jurisdiction.

EPA Method 24 Tests for VOC Content:

To set a universal standard for determining the VOC content of solvents, the EPA promulgated the EPA Method 24 tests as described in:

EPA Reference Method 24 (Determination of Volatile Matter Content, Water Content, Density Volume Solids, and Weight Solids of Surface Coatings, Code of Federal Regulations Title 40, Part 60, Appendix A),

These tests are generally accepted by the industry as reputable third-party verification of VOC content.

Importance of VOC-exemption.

There are thousands of chemicals which react in the atmosphere, but not all have the same effect in forming ozone because they react at different rates. In 2005, the EPA published their guidance for VOC-exempt classification in the Federal register, Vol. 70, No. 176: any substance with a reactivity less than that of ethane would be considered VOC-exempt. The CAA, section 40 CFR 51.100(s), exempts hundreds of chemicals which have negligible photochemical reactivity. VOC-exempt status is the ultimate goal for solvent manufacturers. VOC-exempt products are not included in calculating VOC content of products, and so are free of restrictions on use. EPA VOC-exempt status also may allow a product to be also listed by SCAQMD under its Rule 102 VOC-exemptions. The EPA and local regulators constantly lower VOC content limits, forcing solvent users to switch to low-VOC and VOC-exempt solvents. As a result, there is a growing demand for VOC-exempt solvents which perform as well as conventional solvents but are exempt from regulation and are cost-effective.

First VOC Regulations:

In 1998, the EPA published the first VOC regulations under the Clean Air Act (CAA) for several types of products: Part II Environmental Protection Agency 40 CFR Chapter I Consumer and Commercial Products: Schedule for Regulation; Final Rule 40 CFR Parts 9 and 59 National Volatile Organic Compound Emission Standards for Automobile Refinish Coatings and Consumer Products; Final Rules 40 CFR Part 59 National Volatile Organic Compound Emission Standards for Architectural Coatings; Final Rule

Current EPA VOC Regulations:

Here are the most recent versions of the EPA VOC limits as included in EPA Federal Title 40 Protection of the Environment CFR Part 59:

Subpart B—National Volatile Organic Compound Emission Standards for Automobile Refinish Coatings

Subpart C—National Volatile Organic Compound Emission Standards for Consumer Products

Subpart D—National Volatile Organic Compound Emission Standards for Architectural Coatings
At the bottom of each of the 3 documents, there is a table summarizing the VOC content limits for that category.

Subpart E—National Volatile Organic Compound Emission Standards for Aerosol Coatings This subpart appears to be a work in progress. Several tables at the bottom of the document lists reactivity factors for hundreds of chemicals. The first 3 subparts list VOC contents, so it may be that the EPA is leaning towards the CARB model of reactivity for aerosols.

Updates to VOC Regulations:

The EPA updates their VOC regulations frequently. Here are the links to a history of the Proposed and Promulgated Rules for various sectors: Rule and Implementation Information for Consumer Products-Section 183(e) VOC Rules Rule Information for Architectural Coatings-Section 183(e) VOC Rules Rule and Implementation Information for Automobile Refinish Coatings-Section 183(e) VOC Rules Each page includes a table showing the history of updates to the rules, however, online searches often identify proposed rule changes that are not listed in the table. Each time the rules are updated, there is an entry in the Federal Register but it is difficult to reconcile the Federal Register entries with the EPA site. Many of the rule changes result from petitions to add chemicals to the VOC-exempt list because they can be proven to be negligibly reactive in the formation of ozone. These rule changes are not easily found, except by painstaking review of hundreds of pages of search results to identify specific changes.

Proposed Rule Changes:

The EPA maintains an Action Initiation List (AIL) by month which can be scanned to see if there are any actions with respect to VOC regulation. An archive of past AILs may be found on the Docket located at:http://www.regulations.gov/#!docketDetail;D=EPA-HQ-OA-2008-0265, however, it does not appear to contain a complete or organized compendium.