CDL Hazardous Materials Endorsement (HME)Hazardous Materials RegulationsMedium
A driver is transporting 200 gallons of gasoline (UN1203, Class 3, PG II) and 100 pounds of ammonium nitrate fertilizer (UN1942, Class 5.1, PG III). Which of the following segregation rules applies to this mixed load?
- AGasoline and ammonium nitrate can be loaded together without segregation as their combined quantity is below the placarding threshold.
- BGasoline and ammonium nitrate must not be loaded together in the same vehicle.
- CGasoline and ammonium nitrate can be loaded together in the same vehicle, provided there is a fire-resistant barrier between them.
- DGasoline and ammonium nitrate can be loaded together in the same vehicle, but not in the same transport compartment.
Show answer & explanationAnswer & explanation
Correct answer: B. Gasoline and ammonium nitrate must not be loaded together in the same vehicle.
The segregation table (177.848(e)) prohibits loading Class 3 (flammable liquid) and Class 5.1 (oxidizer) materials together in the same transport vehicle, regardless of quantity, due to the high risk of fire or explosion. The quantities here are irrelevant to this specific segregation rule.
Why the other options are wrong
- A. This is incorrect. Segregation rules are based on hazard class compatibility, not placarding thresholds. Even small quantities of incompatible materials may be prohibited from being loaded together.
- C. This is incorrect. A fire-resistant barrier does not permit the co-loading of Class 3 and Class 5.1 materials when they are otherwise prohibited from being in the same vehicle.
- D. This is incorrect. The segregation rules for Class 3 and Class 5.1 prohibit them from being in the same transport vehicle at all, not just the same compartment.
Segregation of Flammable Liquids and Oxidizers
Flammable liquids (Class 3) and oxidizers (Class 5.1) are highly incompatible and are forbidden from being loaded together in the same transport vehicle due to the significant risk of fire or explosion.
- Class 3 (Flammable Liquids) and Class 5.1 (Oxidizers) are incompatible.
- Must not be loaded together in the same transport vehicle.
- Segregation rules apply regardless of quantity or placarding thresholds.
Memory trick: Some hazmats are like oil and water; they just can't share the same ride.