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Interpretation Response #22-0052

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Arkema – Health Environment and Safety

Individual Name: Steve Schulte

Location State: PA Country: US

View the Interpretation Document

Response text:

April 3, 2023

Mr. Steve Schulte, CHMM, CPP
Hazardous Materials/Dangerous Goods Consultant
Arkema – Health Environment and Safety
9001st Ave
King of Prussia, PA  19406

Reference No. 22-0052

Dear Mr. Schulte:

This letter is in response to your May 16, 2022, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to organic peroxides. In your email, you present a scenario where tert-Butyl hydroperoxide is transported as "UN3103, Organic peroxide type C, liquid, 5.2" which is listed in the Hazardous Materials Table (HMT; § 172.101) as a Division 5.2 material with no subsidiary hazard. However, you note that Note 13 in Column 8 of the Organic Peroxide Table found in § 173.225 indicates that tert-Butyl hydroperoxide requires an additional Class 8 (corrosive) label, in addition to the Division 5.2 label. You ask whether your understanding is correct that a shipment of "UN3103" comprised of tert-Butyl hydroperoxide requires both a Division 5.2 label and a subsidiary Class 8 label.

You are correct that the HMT does not list "UN3103, Organic peroxide type C, liquid, 5.2" with a Class 8 subsidiary hazard. However, as noted in your email, the Organic Peroxide Table in § 173.225 requires tert-Butyl hydroperoxide to have a subsidiary Class 8 (corrosive) label.

I hope this information is helpful. Please contact us if we can be of further assistance.


T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

172.101 and 173.225

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.225 Packaging requirements and other provisions for organic peroxides