Analyze an SDS

DOT Division 4.1: Flammable Solids

Division 4.1 is the DOT division for flammable solids: solids that are readily combustible or may cause or contribute to fire through friction, along with self-reactive materials, solid desensitized explosives and polymerizing substances.

How it is defined

  • Readily combustible solids can ignite easily from a brief contact with an ignition source such as a match and burn rapidly.
  • Self-reactive materials can decompose strongly without oxygen, and are assigned entries by type.
  • Polymerizing substances can undergo a strongly exothermic reaction when they are not stabilized.

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
White with seven vertical red stripes
Symbol
Flame

A diamond with red and white vertical stripes, a black flame, and the number 4.

Packing groups

PG II (medium) and PG III (minor) for flammable solids; self-reactive materials are not assigned a packing group in the same way. How packing groups work.

Common examples

  • Sulfur
  • Matches (safety matches)
  • Naphthalene
  • Certain metal powders
  • Nitrocellulose with alcohol

How it relates to GHS

Corresponds to GHS flammable solids (Categories 1 and 2) and self-reactive substances, shown with the flame pictogram or the exploding bomb for the more severe self-reactive types.

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

  • Control dust and ignition sources.
  • Store cool and away from oxidizers.
  • Do not store self-reactive materials above their control temperature.

Where to find it on an SDS

Section 14 shows Division 4.1, UN number and packing group. 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.

Frequently asked questions

What is a Division 4.1 material?

A Division 4.1 material is a DOT flammable solid, which includes readily combustible solids, self-reactive materials and polymerizing substances.

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