WASHINGTON — An alliance of air-quality regulatory officials has issued a suggested “model rule” for control of VOC emissions from architectural and industrial-maintenance (AIM) coatings that, if adopted by state or regional regulatory agencies, would set sharply lower VOC limits than a national VOC rule that went into effect in 1999.

The suggested model rule is undergoing consideration by air-quality regulatory officials in the northeastern United States, following the proposal’s development by an alliance of two organizations — the State and Territorial Air Pollution Program Administrators (STAPPA) and the Association of Local Air Pollution Control Officials (ALAPCO). The groups are commonly referred to as STAPPA-ALAPCO.

Representatives of the National Paint & Coatings Association and its member companies have voiced opposition to the model rule’s provisions, and are campaigning against its adoption by regulatory agencies. The proposal would set VOC limits that are technically infeasible, the NPCA says.

The proposed model rule essentially duplicates the provisions of a suggested control measure (SCM) issued last year by the California Air Resources Board (CARB), and suggests VOC limits on 47 different types of coatings.

The proposed limits are significantly lower than those required by the EPA’s national VOC rule in a number of coatings categories. The model rule, for example, proposes a VOC limit of 100 grams per liter (g/L) for flat coatings, compared to the national rule’s 250 g/L. Other comparisons are the model rule’s limit of 250 g/L for non-flat high-gloss coatings (national rule – 380 g/L); 150 g/L for non-flat coatings (national rule – 380 g/L); and 250 g/L for industrial-maintenance coatings (national rule – 450 g/L).

The model rule’s proposed limits for other, more specialized coatings are also lower than the national rule in many cases, including lacquer coatings (550 g/L vs. the national rule’s 680 g/L); floor coatings (250 g/L vs. 400 g/L); primers, sealers and undercoaters (200 g/L vs. 350/400 g/L); quick-dry enamels (250 g/L vs. 450 g/L); quick-dry primers, sealers and undercoaters (200 vs. 450 g/L); stains (250 g/L vs. 550 g/L); and a number of other coatings types.

The suggested model rule has been issued, the air-quality alliance says, because the EPA has “overestimated” the effect of the national VOC rule in reducing VOC emissions and, thus, ozone pollution, or smog. The STAPPA-ALAPCO alliance says the model rule will help state and regional air-quality agencies meet the EPA’s national air-quality standards for ozone pollution.

The model rule is among several possible air pollution control measures that were scheduled to be discussed at a special meeting of the Ozone Transport Commission in Washington. The OTC includes air-quality officials from 12 northeastern and Mid-Atlantic states and the District of Columbia, in an area stretching from Virginia to Maine. The commission does not enact air-quality regulations, but can recommend the adoption of such rules by members of the organization.

More information on the STAPPA-ALAPCO model VOC rule is available from the OTC website at www.sso.org\otc\. Information also is available from the STAPPA-ALAPCO website at www.4cleanair.org.