Search

Can Hazmat Change Classes During Transportation?

Posted on 7/31/2025 by Lion Technology Inc.

Materials, hazardous and otherwise, can change states. At different temperatures, water becomes gas, and sand becomes glass.

At room temperature, phosphoric acid is a crystalline solid with a melting point of around 100° F. During transportation, ambient temperatures can range from -40° F to over 200° F. So, it is reasonable that solid phosphoric acid could liquefy, and liquid phosphoric acid can corrode metal packagings and vehicles. 

So, hazmat can change classes during transportation, right? Wrong.

Hazmat Changes Characteristics, Not Classes

For some materials, we do not wait until they exhibit the characteristics of a hazardous material to classify them. Solid phosphoric acid powder is a Class 8 corrosive hazardous material because of its potential to liquefy and become corrosive. Believe it or not, the Hazardous Materials Regulations (HMR) already cover this specific issue.
 
“A liquid, or a solid which may become liquid during transportation, that has a severe corrosion rate on steel or aluminum based on the criteria in 173.137(c)(2) is also a corrosive material.”
[49 CFR 173.136(a)]
Put simply, it is the shipper’s responsibility to classify, name, and package a material as if it will exhibit the most hazardous characteristics possible during transportation.

Can Hazmat Change Classes During Transportation?

How to Pack Shapeshifting Hazmat

Learn all the DOT’s rules for classifying, packaging, marking, labeling, and documenting your hazmat shipments in full compliance with the Hazardous Materials Regulations at Lion’s Hazmat Ground Shipper Certification (DOT) Workshop.

Or browse all Lion’s hazmat shipper training at Lion.com/Hazmat.
 

Tags: hazardous materials, hazmat shipping

Find a Post

Compliance Archives

Lion - Quotes

The online course was well thought out and organized, with good interaction between the student and the course.

Larry Ybarra

Material Release Agent

Well designed and thorough program. Excellent summary of requirements with references. Inclusion of regulations in hard copy form, as well as full electronic with state pertinent regulations included is a great bonus!

Oscar Fisher

EHS Manager

The instructor was very very informative, helpful, understandable and pleasant. This course answered many questions I had, being new to this industry.

Frances Mona

Shipping Manager

The instructor was very engaging and helped less experienced people understand the concepts.

Steve Gall

Safety Leader

The instructor made the class very enjoyable and catered to the needs of our group.

Sarah Baker

Planner

I like Lion's workshops the best because they really dig into the information you need to have when you leave the workshop.

Tom Bush, Jr.

EHS Manager

One of the best trainings I have ever received!

Brandon Morfin

EH&S Manager

Lion is my preferred trainer for hazmat and DOT.

Jim Jani

Environmental Coordinator

Convenient; I can train when I want, where I want.

Barry Cook

Hazmat Shipping Professional

Very well structured, comprehensive, and comparable to live training seminars I've participated in previously. I will recommend the online course to other colleagues with training requirement needs.

Neil Luciano

EHS Manager

Download Our Latest Whitepaper

Shipping papers are a crucial part of safely shipping hazardous materials. See the top 5 mistakes shippers make on shipping papers, and how to avoid them.

Latest Whitepaper

By submitting your phone number, you agree to receive recurring marketing and training text messages. Consent to receive text messages is not required for any purchases. Text STOP at any time to cancel. Message and data rates may apply. View our Terms & Conditions and Privacy Policy.