Ground Level Ozone

Most of us think of ozone as a good thing – but that’s only partially true. Unlike the “good” ozone in the stratosphere that protects us, ground level or “bad” ozone is a colorless gas that forms just above the earth’s surface, where people, animals, and plants live and breathe.

Ground level ozone can cause airway inflammation even in healthy people. Susceptible populations, such as children and the elderly, as well as non-white and low income populations who are more frequently exposed to ground level ozone, are at the highest risk for developing – or worsening – severe respiratory problems.

Volatile Organic Compounds (VOCs)

Ground level ozone is not directly emitted into the air, but results from a reaction between sunlight and two types of pollutants: Nitrogen Oxides (NOx) and Volatile Organic Compounds (VOCs). Also called ‘off-gassing,’ VOCs are chemicals that easily evaporate, particularly on hot, sunny days. Unfortunately, the days with the highest VOC levels are also the summer days when more children and adults are playing or working outside.

While some VOCs carry a strong smell, odorless VOCs can be just as dangerous. Many products in our homes – ranging from paints and adhesives to cosmetics and cleaning supplies – regularly release VOCs such as Acetone, Benzene, and Formaldehyde. Check out our resource guid here.

The ‘Ozone Transport Commission’ (OTC)

Under the Clean Air Act, Congress created an organization called the Ozone Transport Commission (OTC) to develop model rules that states can adopt to reduce ground level ozone, with an additional goal of creating regional consistency. The 13 member states of the OTC, which include the Northeastern and mid-Atlantic regions from Virginia to Maine, have not generally met the EPA’s 2008 standards for ground level pollution, although significant progress has been made.

Currently, nearly all states in the region follow the OTC’s 2006 revised model rule for VOC emission levels. Based on recommendations made by the California Air Resources Board, the emissions standards exceed Federal regulations from 1998, which cover only 48% of consumer products nationwide. Following California’s example, the 2006 OTC rule instead covers nearly 80% of consumer products!

Protecting Marylanders from ground level pollution

As the EPA strengthened air quality standards in 2015, the OTC developed an updated model rule, again based on California’s recommendations: Already adopted by New Hampshire and Delaware, the OTC’s 2014 model rule covers previously unregulated consumer products, while bolstering several existing regulations for a variety of products.

This year, the Maryland Department of the Environment (MDE) proposed adopting the updated rule for VOCs, which would apply to Maryland’s commercial and household products and would reduce VOC emissions in the state by a projected 6.1 million tons per day. The regulations would then be submitted to the EPA for approval as part of Maryland’s State Implementation Plan to further reduce ground level pollution.

Changes to current regulations: Reducing VOCs in products

VOCs are regulated by percentage amounts of a consumer product. Under the proposed regulatory changes, 14 product categories would be subject to more stringent VOC weight limits. For example, beginning on the effective date, VOCs could account for a maximum of 10% of the weight of aerosol engine degreasers, down from 35% under previously adopted limits. Similarly, the VOC limit for shaving gels would be reduced to 4%, while the limit for nail polish remover would drop to 1%.

In addition, 10 new consumer product categories would be subject to VOC limits. The new regulations set a 70% limit for aerosol sanitizers and disinfectants and a 1% limit for non-aerosol versions of the products. VOC levels in automotive windshield cleaners would be limited to 35%, and levels in temporary hair color would be limited to 55%.

Timeline for adopting regulatory changes

Following the initial stakeholder meeting in early April, the MDE accepted public comments and will most likely host an additional stakeholder call in May. On June 6th, the Air Quality Control Advisory Council (AQCAC), which consists of 15 Secretary-appointed members, will meet to review and provide advice on the proposed changes. A public hearing is planned for October, after which the MDE will publish the final regulatory changes in the Maryland Register in December, with an effective date of January 1st, 2017.