Hazardous Materials and Vehicle Marking
This domain covers placarding thresholds, shipping papers, parking and smoking rules, and the equipment a placarded vehicle must carry. Questions are usually threshold questions: does this load need a placard, and which one?
Placards and marking
- Placards are diamond-shaped, 250 millimeters (about 9.84 inches) on each side, and must be readable from the direction of approach.
- Table 1 materials and certain poison-inhalation-hazard materials require placards in any quantity; Table 2 materials require placards at 1,001 pounds or more aggregate gross weight.
- Subsidiary placards may be omitted below 2,205 pounds aggregate gross weight of all hazardous materials, but the primary placard still applies.
- The shipping paper must show the proper shipping name, hazard class or division, identification number, packing group, and total quantity, plus a 24-hour emergency response telephone number. Keep it within reach and in a pouch on the driver's door or in the cab.
Operating rules
- No smoking within 25 feet of a placarded vehicle, including during loading and unloading.
- Park at least 5 feet from the traveled portion of the road, and away from bridges, tunnels, crowds, and open flames.
- Carry a fire extinguisher rated at least 10 BC on a placarded vehicle, plus three warning devices.
- Follow designated hazardous materials routes; the District restricts hazmat from certain tunnels, bridges, and the Capitol area.
Worked example
A truck carries 1,200 pounds of one Table 2 material plus 500 pounds of a different Table 2 material. Reasoning: the threshold is aggregate gross weight of Table 2 materials, so 1,700 pounds exceeds 1,001 and placards are required for both materials.
Traps
- Applying the 1,001-pound rule to Table 1 materials.
- Leaving a placarded vehicle unattended or unlocked.
- Forgetting that subsidiary placards have their own 2,205-pound threshold.
- Assuming the shipper decides the route.