Not much will change for the five-parish Baton Rouge area if a proposed new, tougher ozone standard announced by the U.S. Environmental Protection Agency in late November is adopted.

The EPA proposed a new rule that would lower the ozone standard from 75 parts per billion to between 65 ppb and 70 ppb. The agency also is taking comments on the possibility of lowering it to 60 ppb.

Industry and residents of East Baton Rouge, West Baton Rouge, Ascension, Iberville and Livingston parishes have been living with ozone-related regulations for decades. The area came into compliance with the latest ozone standard late last year, just in time for a tougher standard to be proposed.

One possible change is that the five-parish area may be expanded because the census bureau has changed what constitutes the Metropolitan Statistical Area for Baton Rouge, said Vivian Aucoin, senior scientist with the state Department of Environmental Quality air permits division.

In 2013, the U.S. Census Bureau increased the Baton Rouge MSA to also include Pointe Coupee, West Feliciana, East Feliciana and St. Helena parishes, and it’s unclear if these four parishes will be included in Baton Rouge’s ozone declaration, she said.

EPA uses the Metropolitan Statistical Areas to generally define whether a region meets certain air quality criteria — like ozone. If one monitor’s data fails to meet the standard, the entire area is considered out of compliance.

The decision of whether to add the four parishes to the five in the MSA likely won’t be known until EPA publishes a final rule, Aucoin said. If included, it would mean the four will have a more complex and expensive permitting process for industry and a more complicated process to qualify for federal transportation funding — just as Baton Rouge has to do now.

In addition, construction projects like a new community center built with federal funds would require an analysis of pollution caused by the construction and the added traffic the center would create to make sure they don’t add to the ozone problem.

Although it involves more work, Aucoin said she’s not aware of anyone being denied a project because of the requirement.

Ozone is not a pollution that is released but is instead formed when volatile organic compounds and nitrogen oxides from industry, vehicle traffic and other sources combine in the air during hot, sunny days. When there is little wind, this formed ozone can accumulate and lead to breathing or other health problems, especially for vulnerable populations like children or the elderly.

EPA estimates that health benefits to the public by lowering the standard, including reducing asthma attacks, heart attacks and premature deaths, will far outweigh any costs associated with meeting the new rule.

At 70 parts per billion, there could be a savings from the health benefits realized of anywhere from $6.4 billion to $13 billion a year by 2025. The annual cost is estimated to be $3.9 billion.

At 65 parts per billion, the annual health benefits realized by 2025 are estimated to be between $19 billion to $38 billion, while the cost is estimated to be $15 billion, according to EPA.

Opponents, such as Gov. Bobby Jindal and U.S. Rep. and newly elected U.S. Sen. Bill Cassidy, R-La., say lowering the standard during a time of economic recovery will cost jobs and economic development while bringing minimal returns.

Supporters, such as the American Lung Association and the Natural Resources Defense Council, applaud the proposed lower standard as being a benefit to the health of the public.

“It’s critically important to people’s health and economic development in the state,” said Marylee Orr, executive director of the Louisiana Environmental Action Network.

Over the years, LEAN has been one of the main groups that has pushed for more action on meeting the federal ozone level in the five-parish area around Baton Rouge. Although industry has progressively improved its ozone response, it’s frustrating to see elected officials ignore the importance of ozone standards to the detriment of the health of state residents, she said.

“They never seem to talk about what the real cost is,” she said, which includes emergency room visits or missed school days because of asthma or other health problems.

Areas need to meet an ozone pollution standard of 75 parts per billion, which is calculated by taking the fourth-highest daily maximum eight-hour average ozone concentration for three years and then averaging those numbers.

The determination on whether an area meets the standard that EPA ultimately adopts next year will depend on air monitoring information gathered in 2014, 2015 and 2016. That means there is still time for areas in the state to see improvements in their ozone average to possibly avoid being out of compliance.

After decades of work, the five-parish area of Baton Rouge already has emission control rules for the two pollutants that cause ozone to form — volatile organic compounds and nitrogen oxides.

“We have everything in place for the five-parish area,” Aucoin said.

Richard Metcalf, director of environmental affairs with the Louisiana Mid-Continent Oil and Gas Association, agreed and said that after dealing with the ozone issue for more than 20 years, industry in the Baton Rouge area will continue with the current work.

In addition, he said, the association and the Louisiana Chemical Association have been working with industrial facilities in other areas of the state, like New Orleans, where ozone will be a new concern, to try to educate people on what’s coming down the line.

“They really haven’t dealt with this,” Metcalf said of the New Orleans area.

The additional permit and other potential changes have people’s attention, he said, but it really shouldn’t result in a slowdown in economic growth in the Baton Rouge to New Orleans corridor.

There are rules that have been in place in the five-parish area around Baton Rouge that could help other areas, he said. These are rules that other areas of the state can live with, “because we’ve lived with them for 20 years,” Metcalf said.

In order to better help other areas of the state facing ozone issues for the first time, Metcalf said the Louisiana Mid-Continent Oil and Gas Association and the Louisiana Chemical Association have put together money to use computer modeling being developed by DEQ to pinpoint just where and what pollution needs to be reduced to meet the ozone standard in each area.

One size won’t necessarily fit all areas of the state because each area has a different make-up of pollution sources that contribute to the problem.

While Baton Rouge is heavily industrial, Lafayette doesn’t have much of a heavy industrial base and instead is primarily concerned with vehicle traffic. New Orleans, Metcalf said, seems to be a mix of vehicle traffic and industry.

The computer modeling being developed by DEQ will allow the testing of different reductions of different pollutants to see what will work and how reductions could help regionally.

The focus, Metcalf said, “is how to make it happen.”

It also will matter just how low EPA decides to set the standard, which according to the proposed rule, is between 65 to 70 ppb but with comments being received for a standard as low as 60 ppb.

“Each area is going to have to be examined depending on how the benchmark is set,” said Henry Graham, vice president of environmental affairs and general counsel with Louisiana Chemical Association.

The EPA and state DEQ program “Ozone Advance” is designed to help areas make pollution reduction choices before the new, tougher standard is put in place and is being used to get the word out to other parts of the state to reduce emissions now.

“The Baton Rouge group is trying to help the others because we’ve learned a lot,” Graham said. “Our main thing is if you can stay in attainment, do everything you can to do that. Don’t sit back and wait to see what standard comes out and then decide what to do.”

Follow Amy Wold on Twitter, @awold10.