Cuisine Solutions Ammonia Release

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Accident Description

Accident: Cuisine Solutions Ammonia Release

Location: Location: Sterling, VA

Accident Occurred On: 07/31/2024 | Final Report Released On: 09/25/2025

Accident Type: Release

Investigation Status: The CSB's final report was released on September 25, 2025.

A July 31, 2024, ammonia release at Cuisine Solutions, Inc., a food processing facility in Loudon County, VA led to forty people being evaluated at local hospitals. Of those, four were admitted, one to the Intensive Care Unit. The facility is a commercial food preparation plant with approximately 350 employees located about 30 miles from Washington D.C.

Final Reports

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Recommendations

Cuisine Solutions Inc. Sterling Site

2024-03-I-VA-3

Reduce the likelihood or mitigate the consequences of liquid or two-phase atmospheric discharges from the ammonia refrigeration emergency pressure relief system at the Sterling plant. At a minimum:

a. Identify liquid or two-phase release scenarios, particularly for horizontal surge drums and other vessels containing saturated liquid with little vapor space;

b. Implement engineering controls to reduce the likelihood of high liquid level, overfill, or boiling overpressure scenarios;

c. Implement engineering controls to mitigate the consequences of these scenarios where their likelihood cannot be acceptably reduced, such as through emergency pressure control systems, atmospheric knockout drums, or automatic shutdown systems; and

d. Contract a competent third party to audit the pressure relief systems. The audit should ensure that (i) all relevant relief scenarios have been identified, (ii) preventive and mitigative engineering controls adequately address the hazards, and (iii) engineering controls are maintained in such a way that they function properly when required.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary

2024-03-I-VA-4

Implement an electronic process data historian and management system to ensure that critical process parameters are collected, tracked, and stored. The system should be available to refrigeration technicians so that they can monitor the refrigeration system and respond to and investigate process upsets.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary

2024-03-I-VA-5

Update the Cuisine Solutions Sterling site’s Emergency Action Plan using guidance such as the IIAR’s Critical Task Guidance for Ammonia Refrigeration System Emergency Planning. At a minimum, the updated plan should:

a. Address indoor and outdoor ammonia releases separately, including the distinct alarms and responses to them;

b. Clearly specify appropriate evacuation routes and muster points, including alternates;

c. Provide guidance for using windsocks to remain upwind of a release during evacuation;

d. Implement shelter-in-place strategies, emergency protective equipment, and emergency shutdowns, as appropriate; and

e. Include requirements to conduct annual ammonia release drills that include all onsite personnel (including corporate employees). The annual drills should include separate indoor and outdoor ammonia release scenarios and address the use of windsocks to assist with determining evacuation routes, alternate evacuation routes, muster points, and consideration for the decision to shelter-in-place. Additionally, the drills should exercise each evacuation alarm, emergency protective equipment, and emergency shutdowns, where appropriate.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary

2024-03-I-VA-6

Add an alarm or alarms specific to ammonia releases, so that workers can properly respond to a release. The alarm response should be documented in the updated Emergency Action Plan, and may include multiple distinct alarms and responses, such as one for shelter-in-place and one for evacuation.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary
International Institute of All-Natural Refrigeration (IIAR)

2024-03-I-VA-1

Update ANSI/IIAR 2 to include guidance for preventing or mitigating liquid or two-phase atmospheric discharges from emergency pressure relief systems, such as the guidance in API Standard 521, Pressure-relieving and Depressuring Systems. At a minimum, the guidance should:

a. Identify at-risk scenarios such as horizontal surge vessels and other vessels containing saturated liquid with little vapor space;

b. Address design considerations and controls to reduce the likelihood of identified scenarios leading to overpressure or equipment failure and ensure vapor-liquid disengagement (the separation of vapor from liquid) during pressure relief for identified scenarios; and

c. Require mitigative safeguards in cases where vapor-liquid disengagement during pressure relief cannot be reliably ensured. This should also include alternative disposal systems where applicable.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary

2024-03-I-VA-2

Update ANSI/IIAR 2 to include a requirement to assess whether emergency pressure relief devices discharge to a safe location, such as with a dispersion analysis.

Status: Open - Awaiting Response or Evaluation/Approval of Response

Open - Awaiting Response or Evaluation/Approval of Response (O - ARE/AR) - The recipient has not submitted a substantive response, or the evaluation by CSB staff of a response is pending, or the Board has not yet acted on staff recommendation of status.

Recommendation Status Change Summary