Analyze an SDS

DOT Class 5: Oxidizers and Organic Peroxides

DOT Class 5 covers oxidizing substances and organic peroxides. Division 5.1 oxidizers are materials that may cause or enhance the combustion of other materials, and Division 5.2 organic peroxides are unstable compounds that can burn, decompose violently or react dangerously.

How it is defined

  • Oxidizers supply oxygen or similar to a fire, so they intensify burning of other materials.
  • Organic peroxides contain the two-oxygen -O-O- structure and are often temperature sensitive.
  • Both divisions need segregation from combustible and flammable materials.

Summary of 49 CFR Parts 171 to 180. The regulations and the Hazardous Materials Table (49 CFR 172.101) control any shipment.

Label and placard

Colors
Yellow (5.1), red over yellow (5.2)
Symbol
Flame over a circle

Both divisions use a flame over a circle. See the division pages for the color differences.

Packing groups

Packing groups I, II and III for Division 5.1. Organic peroxides are not given packing groups in the same way; they are assigned by type. How packing groups work.

Common examples

  • Ammonium nitrate, potassium permanganate, calcium hypochlorite (5.1)
  • Hydrogen peroxide solutions at high strength (5.1)
  • Benzoyl peroxide, methyl ethyl ketone peroxide (5.2)

How it relates to GHS

Corresponds to GHS oxidizing gases, liquids and solids (flame over circle, GHS03) and organic peroxides (grouped with self-reactive substances).

DOT classes and GHS classes are assigned under different rules, so a product can have different severity labels in each. See also all GHS hazard classes.

Safe handling reminders

  • Store oxidizers away from fuels, solvents and organic materials.
  • Keep organic peroxides at or below the temperature on the SDS or label.
  • Do not return spilled product to the original container.

Where to find it on an SDS

Section 14 shows Class 5, the division (5.1 or 5.2), UN number, packing group and ERG guide number. Look in Section 14: Transport information. Hazard classification for the workplace is in Section 2. You can also see how a UN number points to a response guide on the UN and NA numbers page.

Divisions in Class 5

Division 5.1
Oxidizer
Division 5.2
Organic peroxide

Frequently asked questions

What is the difference between 5.1 and 5.2?

Division 5.1 is oxidizing substances that help other materials burn. Division 5.2 is organic peroxides, which are unstable compounds that may burn or decompose violently on their own.

General reference only. It does not replace the supplier's SDS or the current federal regulations.