Dow in Louisiana

July 2023 LAO incident

On July 14, 2023, an explosion followed by subsequent fires occurred at Dow's Louisiana Operations' Glycol 2 plant in Plaquemine, Louisiana. This website provides the most up-to-date information and resources.

What happened

At approximately 9:15 p.m. Central Time on Friday, July 14, there was an explosion followed by subsequent fires at Dow's Louisiana Operations in Plaquemine, Louisiana, resulting in the release of ethylene oxide and other compounds. The incident occurred in Dow's Glycol 2 Unit.

Out of an abundance of caution, Iberville Parish declared a shelter-in-place for one-half mile on the south side of the site following the event. The shelter-in-place was lifted at 3:42 a.m. and Highway LA 1 was reopened at 8:45 a.m.

At approximately 5:00 a.m. Central Time on Sunday, July 16, the fire was fully extinguished. Water and air monitoring conducted during and after the event consistently showed results below applicable federal and state standards and guidelines.

After a safe and successful de-inventory of impacted equipment, Dow welcomed back all employees to the Plaquemine site on Monday, August 7. Dow has continued to safely progress through assessment and recovery activities and promptly initiated an investigation (RCI) into the incident. On Wednesday, September 6, Dow reported the emissions from the incident in accordance with state regulations.

The purpose of the RCI is to help fully understand the cause, identify corrective actions and incorporate those actions into our recovery plans at Louisiana Operations and leverage to other sites. We are dedicated to learning from this event and preventing incidents such as this from happening again.

Important information

During the incident at Dow’s Glycol 2 unit and subsequent stabilization activities, Dow took steps to ensure all workers were safe and accounted for. Dow also helped mitigate community and environmental impact, including air and water monitoring, to ensure immediate detection of any potential risks and to protect the health of Dow employees and the community. There were no injuries reported.

Dow has complied with all regulatory reporting requirements throughout this process. This included initial notifications to the national response center, Louisiana State Police, Louisiana Department of Environmental Quality (LDEQ), Iberville Local Emergency Planning Committees and West Baton Rouge Local Emergency Planning Committees. Dow provided air monitoring and water sampling data to LDEQ during and after the incident. Monitoring and sampling have consistently shown results below applicable federal and state standards and guidelines.

The site transitioned to its routine air monitoring activities on August 23, 2023. Third-party air monitoring service in the near community concluded on the same date.

Dow follows all OSHA and other regulatory requirements with clearly defined processes and protocols and monitoring capabilities to help protect employees and the communities in which Dow operates.

Dow will continue to work with members of the community to listen to their concerns, answer their questions and address their needs and continue the partnership Dow has fostered through decades of community engagement.

Dow reported the emissions from the incident to the Louisiana Department of Environmental Quality (LDEQ). Dow took extensive measures to ensure accuracy in calculating emissions from the incident and each step of the analytical process was evaluated by a third-party expert, Baker Engineering and Risk Consultants.

The emissions report includes air and water emissions data associated with the incident and confirms that ethylene oxide and ethyl chloride were the main sources of emissions, with 31,525 and 59,609 pounds released respectively. Monitoring data was consistently below applicable federal and state standards.


Because a large volume of water from firefighting and fire suppression activities went to Dow's internal water management system, Dow initiated regular water sampling and analysis following the event. Water sampling at internal checkpoints and at the final outfall, with testing by a third-party laboratory, began on the morning of July 15, 2023. All findings were reported to the Louisiana Department of Environmental Quality (LDEQ). All sample results have been below federal and state water quality reportable standards.

To better manage the large volume of water from firefighting and fire suppression activities, and additional water flow from damaged utility and cooling water lines, Dow requested authorization of anticipated bypass from LDEQ on July 17, 2023. The request was approved the next day, with additional requirements for sampling and reporting.

A water bypass extension request was prepared on July 27, 2023 as a precautionary measure in case the firewater curtain/spray, which assisted in suppressing any potential fires during the response and assessment process, was still needed.

Dow withdrew the request for extension of the bypass authorization with LDEQ on July 31, 2023. The original request for the bypass under the water discharge permit expired August 1, 2023. Water quality remains normal.


Air monitoring specifically for ethylene oxide was conducted in the community using handheld monitors (MultiRAE) that provide immediate readouts. This monitoring was conducted by third-party experts and the results were non-detect throughout the air monitoring time period. Monitoring data was shared with LDEQ.

In addition to ethylene oxide air monitoring, Dow monitored for other hazardous levels of combustible gases, including ethyl chloride. Dow provided air monitoring data to LDEQ during and after the incident. Monitoring consistently showed results below applicable federal and state standards and guidelines.

With safety at the forefront, Dow will continue to work with the community to listen to their concerns, answer their questions, and address needs and to foster the partnership Dow has strived to maintain through more than 65 years of continued engagement.

To help ensure incidents like the Glycol 2 July 14, 2023 event do not happen again, Dow has completed a thorough investigation into the incident. The investigation found that portable work lights used to temporarily illuminate the inside of the vessel during a May 2023 maintenance turnaround remained in the vessel after the work was complete. These portable lights degraded over time and formed debris. The debris passed through and damaged unit equipment, ultimately resulting in ethylene oxide (EO) igniting inside a line and then over-pressuring a process vessel and surrounding equipment.

As we move forward, the Company is acting on findings from the internal investigation, including enhancing our vessel closure work practices and continuing to develop technology solutions to continuously improve our processes.

Community resources

Contact Dow Louisiana Operations

The community is invited to send inquiries to

We also provide regular information on our social media channels.

Contact local emergency preparedness

Local offices of emergency preparedness help community residents prepare for and respond to emergencies of all types in times of crisis to save lives and property.

Iberville Emergency Preparedness
(225) 687-5140

West Baton Rouge Emergency Preparedness
(225) 346-1577

Media contact

Media professionals may send press inquiries to

All other inquiries should be sent to

Additional information

Ethylene oxide educational info

Ethylene oxide safety facts - American Chemistry Council

Ethyl chloride educational info

General Q&A