Diluents and Thinners
Volatile Organic Compound (VOC) Content Limits
Introduction
This document summarizes the regulations affecting the content limits of Volatile Organic Compounds (VOCs) for Consumer Diluent and Thinner Products. For a quick introduction on how to most easily interpret these pages, link to How to Use the VOC and MIR Rules.
Skip to regulations:
- South Coast Air Quality Management District (SCAQMD)
- California Air Resources Board (CARB)
- Massachusetts
- Texas
- Ozone Transport Commission (OTC) (NY, NJ)
- Lake Michigan Air Directors Consortium (LADCO) (MI, OH, IL, IN)
VOC Content Limits in California:
South Coast Air Quality Management District (SCAQMD)
The most comprehensive regulations are issued by the SCAQMD of southern California. Rule 1143 Consumer Paint Thinners & Multi-Purpose Solvents established VOC content limits of 25 g/liter effective January 1, 2011 for both Consumer Paint Thinners and Consumer Multi-Purpose Solvents. The definitions in Rule 1143 are as follows:
“CONSUMER MULTI-PURPOSE SOLVENTS are any liquid products designed or labeled to be used for dispersing or dissolving or removing contaminants or other organic materials for personal, family, household, or institutional use.”
“CONSUMER PAINT THINNERS are any liquid products used for reducing the viscosity of coating compositions or components for personal, family, household, or institutional use.”
A loophole which allowed manufacturers to skirt Rule 1143 by creatively labelling their product has been plugged by the California Air Resources Board which has incorporated Rule 1143 into its provisions effective January 1, 2015. (But this applies only to the SCAQMD district. Elsewhere in California, a limit of 3% VOC content by weight applies.) Check the definitions to determine if the manufacturer’s product meets one of them. If so, then if they are selling product in California, they must act immediately to come into compliance.
California Air Resources Board (CARB)
CARB has adopted Article 2: Regulation for Reducing Emissions from Consumer Products, which includes the following product definitions:
“General Purpose Cleaner” means a product labeled to clean a variety of hard surfaces including, but is not limited to, products designed or labeled for general floor cleaning, kitchen, countertop, or sink cleaning, and cleaners designed or labeled to be used on a variety of hard surfaces such as stovetops, cooktops, or microwaves.
“Multi-purpose Solvent” means any liquid product designed or labeled to be used for dispersing, dissolving, or removing contaminants or other organic materials.
The definitions of solvents in the SCAQMD and CARB Rules are fairly close. Therefore, we should assume that a solvent regulated by SCAQMD Rule 1143 would also be regulated by CARB Article 2. CARB Article 2 includes the following VOC Content limits:
Product | Effective Date | VOC Content Limit (% by Weight) |
General Purpose Cleaner Aerosol | 12/31/08 | 8 |
General Purpose Cleaner non-Aerosol | 12/31/12 | 0.5 |
Multi-purpose Solvent | 12/31/13 | 3 |
Paint Thinner | 12/31/13 | 3 |
Note that the SCAQMD rules are more stringent than CARB, or any of the rules in the jurisdictions which follow. CARB enforces its VOC content rules. See CARB Enforcement.
Massachusetts
The VOC regulations are published in one long document, 310 CMR 7.00 Air Pollution Control Regulations. There is a category for Cleaners, but not for thinners. Source: Table 2. VOC Content Limits for Consumer Products Effective January 1, 2009, starting page 401.
Consumer Product | VOC Content Limit (% by Weight) |
General Purpose Cleaner Aerosol | 10 |
General Purpose Cleaner non-Aerosol | 4 |
Texas
Under TITLE 30 ENVIRONMENTAL QUALITY, PART 1 TEXAS COMMISSION ON ENVIRONMENTAL QUALITY, SUBCHAPTER E: SOLVENT-USING PROCESSES, DIVISION 6: INDUSTRIAL CLEANING SOLVENTS, RULE §115.463 Control Requirements: the VOC content of cleaning solutions is limited to 0.42 pound of VOC per gallon of solution.
Ozone Transport Commission (OTC)
The OTC states: Connecticut, Delaware, the District of Columbia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and Virginia, have specifically adopted the CARB rules for Paint Thinners and Solvents.
The Lake Michigan Air Directors Consortium (LADCO)
Indiana, Illinois, Michigan, Wisconsin and Ohio. The stated policy is to adopt CARB rules. Ohio has published a list of VOC content limits which matches the current CARB limits before the new updates come into effect 2015 – 17.
Summary:
SCAQMD’s rules are the strictest. Any manufacturer selling product into SCAQMD must meet them. CARB’s rules, which apply everywhere in California, are less strict than SCAQMD. Many other states have adopted CARB’s rules. A manufacturer not selling in SCAQMD should adopt CARB rules, as they are the de facto standard for most of the US.