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Regulating air emissions

| By Dorothy Lozowski

There have been several recent announcements regarding regulatory changes that affect the chemical process industries (CPI). One of the latest is a set of final rules announced on April 9 by the U.S. Environmental Protection Agency (EPA; that significantly limits emissions of air pollutants from chemical manufacturing facilities. The main compounds targeted are ethylene oxide (EtO) emissions from synthetic organic chemical production and chloroprene emissions from neoprene manufacture. Describing these chemicals as “air toxics,” the EPA points out that these two chemicals can have serious health effects in small quantities, and the new rule is expected to reduce related cancer risks in communities near facilities that emit them. According to the EPA, the rule will reduce emissions of these two compounds by nearly 80%.

In an earlier announcement on March 14, the EPA had disclosed its final rule specifically for EtO commercial sterilization facilities, which was aimed at reducing EtO emissions from those facilities by 90%.


Rule to reduce toxic air emissions

One of the requirements in the “Final Rule to Strengthen Standards for Synthetic Organic Chemical Plants and Polymers and Resins Plants” relates to improving the efficiency of flares that are used to control pollution. The EPA states that it is also finalizing stronger standards for heat exchangers, process vents and storage vessels. Emission-control exemptions from startup and shutdown operations are being eliminated.

The rule further requires fenceline monitoring of six compounds. In addition to EtO and chloroprene, the compounds include benzene, 1,3-butadiene, ethylene dichloride and vinyl chloride. The EPA cites that this type of monitoring has been very effective in identifying and reducing benzene emissions at petroleum refineries. “Action levels” that will prompt corrective action from the owners and operators have been defined for the monitored chemicals. Fenceline monitoring for chloroprene is required to begin 90 days after the rule goes into effect. There is a two-year deadline for monitoring of the other five chemicals.

The EPA did make adjustments to the proposed rule based on consideration of public comments. For example, EtO flare limit loads were not included, and emissions control levels for chloroprene from process vents and storage tanks were revised.

The American Chemistry Council (ACC; responded to the release of the final rule with a statement that stated in part: “We are reviewing the details of this final rule as well as its impacts on vital industries across the country. This rule will have significant implications on the production of key chemistries such as ethylene oxide, which supports national priorities like electric vehicle battery development, domestic semiconductor manufacturing, and healthcare access.” The ACC raised several concerns over the rule, including the toxicity value for ethylene oxide that was used by the EPA. Full details of the EPA’s final rule and the ACC’s statement can be found on their respective websites.


Update to recent SEC rule

Last month’s column discussed a final ruling by the U.S. Securities and Exchange Commission (SEC; regarding reporting of climate-related risks. At the time of this writing, implementation of that rule has been paused, pending the outcome of legal challenges. ■

Dorothy Lozowski, Editorial Director