On Nov. 26, 2014, the Washington, D.C.-based U.S. Environmental Protection Agency announced a proposal to reduce the National Ambient Air Quality Standard (NAAQS) for ground-level ozone. The existing National Ozone Standard, last strengthened in 2008, sets the acceptable level of ozone at 75 parts per billion (ppb); the proposal calls for lowering that level to 65-70ppb, or even as low as 60ppb. The National Association of Manufacturers, Washington, has called the new proposed standard the “the most expensive regulation in history,” and its passage could result in widespread effects felt across the nation and a wide array of industries, including roofing.
Ozone NAAQS and Nonattainment
Tropospheric (ground-level) ozone is one of six “criteria” pollutants regulated by the EPA, pursuant to the 1990 Clean Air Act, because it has negative human-health impacts and can be damaging to vegetative growth. Ozone is formed when volatile organic compounds (VOCs) and nitrogen oxides (NOx) combine with sunlight. Significant anthropogenic (manmade) sources of VOC and NOx emissions include industrial and manufacturing facilities, vehicle exhaust, gasoline vapors, and solvents used in consumer and commercial coatings and paints.
The ozone NAAQS sets permissible ozone levels; those states and regions that do not meet those thresholds are designated as “nonattainment” areas. A nonattainment designation requires that the state develop and submit a State Implementation Plan (SIP) to the EPA, which outlines the steps that will be taken to reach and maintain compliance, or “attainment”. The steps that a state may take to work toward ozone attainment are varied but often include control measures over manufacturing and industrial processes; regulations aimed to reduce VOC emissions from paints, coatings, and manufacturing processes; or voluntary measures, such as programs that encourage the use of mass transit to reduce vehicle usage.
Additionally, the nonattainment designation comes with specific mandates from the EPA. These include tougher permitting requirements for new or expanding facilities, potential loss of federal highway and transit funding, EPA oversight in permitting, and requirements to “offset” any new emissions sources by reducing emissions in existing operations or by purchasing emissions credits from others.
Many states and regions, including California and the majority of the Northeast’s I-95 corridor, are still working to comply with the 2008 ozone standard’s 75ppb level. The proposal to lower the existing ozone standard to within the range of 65-70ppb will result in a significant increase in nonattainment areas across the country, which will in turn result in growth of stationary source restrictions and state-level regulations as states develop SIPs for achieving lower ozone levels.
The effects of a stricter ozone standard will be felt across the nation and in a wide variety of industries. “Background ozone”, or the ozone levels that would exist regardless of the presence of industry, is 30ppb or higher in most areas. For such regions, lowering the standard from 75ppb to 65ppb would represent a mandate to reduce anthropogenic ozone by more than 20 percent. Additional reductions may prove difficult to achieve and costly, especially for those areas of the country that have already implemented control measures to achieve attainment with the 2008 Standard.
Effects on the Roofing Industry
One area of particular significance to the roofing industry will be VOC regulations for architectural and industrial maintenance (AIM) coatings, as well as for industrial adhesives and sealants, which are used in the application of certain roof systems and for continued maintenance and protection of many roofs. The VOC content for a variety of AIM coatings is regulated on the national level by the EPA. Additionally, there are more stringent VOC regulations in place today across the majority of the Northeast, in several Great Lakes states, and in California’s 35 air districts for AIM coatings and adhesives and sealants as part of those states’ and regions’ SIPs for reaching attainment on existing ozone standards.
While there are regulatory bodies, such as the California Air Resources Board, Ozone Transport Commission and the Lake Michigan Air Directors Consortium that provide guidance on ozone attainment, it is ultimately left up to the states (and in the case of California, individual air districts) to develop and implement VOC regulations. As such, VOC regulations vary from state to state and region to region with rules that contain disparate VOC content limits, compliance dates, and record-keeping and reporting requirements, which can make compliance highly challenging.
Purpose of VOCs in Roof Coatings
VOCs are included in a wide array of coatings for several reasons. Solvent-based coatings can be used as an alternative to waterborne technologies, especially where freeze/thaw resistance and product application and storage in cooler climates or in winter months is required. VOCs are used to dissolve solids to keep coatings in a liquid phase, allowing for them to be applied prior to the solvent flashing out and the product curing to form a solid layer. Furthermore, coatings may be formulated with VOCs because of the solvents’ ability to soften the substrate that the coating is being applied to, improving the application and ultimate performance of the coating.
As new, stricter VOC regulations are introduced and VOC content limits are lowered in different roof coating, adhesive and sealant product categories, several negative consequences may occur. First, it may become more difficult to apply the product or to apply the product at an appropriately thin layer. Additionally, the performance of the product may be negatively impacted, which could result in the need for additional product application throughout the lifetime of the roof or, in extreme cases, a reduced life-span of the roof. Although there are many excellent waterborne technologies available, the use of water-based coatings may not be an acceptable alternative in all situations or in all roof systems.
The Path Forward
The ozone NAAQS’s publication in the Federal Register begins a 90-day comment period, which will be supplemented by several public hearings in the early months of 2015. Should the rulemaking continue forward and a lower ozone standard be approved, the EPA will begin designating attainment and nonattainment areas, which will start the process for the development of SIPs containing a host of new regulations across the country.
For manufacturers, specifiers and contractors alike, an influx of VOC regulations will prove challenging. Formulators will be forced to create high-performing products using lower-solvent content or through the use of exempt solvents; applicators will need to be aware of the rules in place to ensure they are applying compliant products; end-users will need to learn that products they have had in the past may no longer be available. Even under today’s ozone standard, keeping apace of the multitudinous and constantly changing VOC regulations is a large task. EPA’s final determination of a new ozone standard could prove to have significant and long-term ramifications that will be felt for many decades to come.