Over The Road Tanks Flashcards
What are the primary types of railcars used in hazmat transportation?
Pressure tank cars, non-pressure tank cars, boxcars, hopper cars.
What is the gross weight capacity of modern railcars in the U.S.?
286,000 lbs.
What markings are commonly found on railcars?
Reporting marks, car numbers, empty weight, placards, qualification dates, pressure relief info, car specs, and commodity names.
What pressure do pressurized tank cars typically operate at?
Above 40 psi.
What types of materials do pressure tank cars transport?
Liquefied gases, flammable, non-flammable, toxic, and/or compressed gases.
What key safety feature do pressure tank cars have to prevent leaks?
All fittings and valves are located under a protective dome on top.
What pressure range do non-pressurized tank cars typically operate under?
Below 25 psi.
What is the most common general-service non-pressure tank car?
DOT-111.
What hazardous materials can DOT-111 cars carry?
Flammable liquids, corrosives, and some hazardous chemicals.
What tank car was introduced as a safer alternative to DOT-111?
DOT-117.
What improvements does the DOT-117 have over the DOT-111?
Thicker steel shell, full-height head shields, thermal protection, improved bottom outlet valves.
Why was the DOT-117 tank car developed?
After the 2013 Lac-Mégantic disaster to improve crude oil and ethanol transportation safety.
What tank car is designed for transporting refrigerated liquefied gases?
DOT-113.
What type of insulation does a DOT-113 cryogenic tank car use?
Vacuum insulation with an inner and outer tank.
What is a major hazard of cryogenic tank cars?
Rupture can cause rapid gas expansion and overpressurization.
What is the purpose of a boxcar in hazmat transport?
Encloses cargo to protect from the elements; may transport hazardous goods in totes or drums.
What are the two types of hopper cars?
Open-top and covered hopper cars.
What materials are commonly transported in hopper cars?
Dry bulk freight like cement, fertilizer, grain, and coal.
What are the most common types of road trailers for hazardous materials?
MC331, MC338, DOT406, DOT412, TC423, tube trailers, dry bulk, vacuum tankers, mixed cargo, intermodal tanks.
What road trailer is used for transporting liquefied compressed gases under high pressure?
MC331.
What’s the working pressure range of an MC331 trailer?
100-500 psi.
What hazardous materials are transported in an MC331?
LPG, ammonia, chlorine, propane.
What road trailer transports refrigerated liquefied gases?
MC338.
What pressure range do MC338 cryogenic trailers operate at?
25-500 psi.
What type of insulation do MC338 trailers use?
Vacuum insulation (like DOT-113 railcars).
What road trailer is used for gasoline, diesel, and alcohol-based fuels?
DOT406.
What’s the working pressure for a DOT406 trailer?
3-5psi
What road trailer is used for highly corrosive liquids?
DOT412.
What design feature identifies a DOT412 trailer?
Small diameter with external ring stiffeners.
What road trailer is used for transporting emulsions and water-gel explosives?
TC423.
What trailer is designed for high-pressure gas cylinders in clusters?
Compressed gas/tube trailer.
What is the maximum pressure for a gas tube trailer?
250 bar (~3,625 psi).
What trailer is used for non-hazardous bulk powders like cement or flour?
Dry bulk cargo trailer.
What trailer is used for transporting liquid, solid, or sludge waste?
Vacuum tanker.
What type of container is used for multimodal transport across ships, trains, and trucks?
Intermodal freight container.
What is the standard width of an intermodal shipping container?
8 feet.
What is the primary advantage of intermodal tank containers?
They allow transport of hazardous liquids across multiple modes without unloading.
What is the primary material used in intermodal tank containers?
Stainless steel with insulation and a protective layer.
What is the standard volume range of intermodal tank containers?
4,600 to 6,900 U.S. gallons.
What is the primary regulatory body overseeing hazardous material transport in the U.S.?
Department of Transportation (DOT).
What regulatory body oversees rail transport of hazmat materials?
Federal Railroad Administration (FRA).
What regulation governs hazardous material transportation safety?
49 CFR Parts 100-185.
What is the purpose of a placard on a railcar or truck?
Indicates hazard class of transported material per DOT/ERG guidelines.
What marking must be on a pressure relief device of a hazmat tank car?
Set pressure and flow capacity.
What is the main safety concern for transporting cryogenic liquids?
Rapid expansion if containment fails, leading to asphyxiation or explosion risk.
What is a ‘manway’ on a tank car or trailer?
An access point for loading/unloading, maintenance, or inspection.
What is a bottom outlet valve, and which tank cars typically have them?
A drain valve for unloading, found on non-pressurized tank cars (DOT-111, DOT-117).
