CDL Hazmat Endorsement Exam
Hazmat Classes Practice Questions
35 practice questions with detailed explanations — aligned to the CDL Hazmat Endorsement Exam.
Q1.Hazard Class 1 materials are defined as:
A.GasesB.ExplosivesC.Flammable LiquidsD.CorrosivesB. ExplosivesExplanation: Class 1 consists of Explosives, divided into six divisions (1.1 through 1.6) based on their hazard level.
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Q2.Which Division of Class 1 explosives presents a 'Mass Explosion' hazard?
A.Division 1.1B.Division 1.4C.Division 1.5D.Division 1.3A. Division 1.1Explanation: Division 1.1 explosives (like dynamite) have a mass explosion hazard, meaning the entire load could explode virtually instantaneously.
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Q3.Hazard Class 2 is comprised of:
A.GasesB.Flammable SolidsC.OxidizersD.Radioactive materialsA. GasesExplanation: Class 2 covers Gases, including flammable (2.1), non-flammable/non-poisonous (2.2), and poison gases (2.3).
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Q4.Propane is an example of which Hazard Class and Division?
A.Class 3B.Division 2.1C.Division 2.2D.Class 4.1B. Division 2.1Explanation: Propane is a Flammable Gas, which falls under Class 2, Division 2.1.
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Q5.What defines a Class 3 material?
A.Flammable and Combustible LiquidsB.Flammable SolidsC.OxidizersD.CorrosivesA. Flammable and Combustible LiquidsExplanation: Class 3 includes Flammable Liquids (flash point <140°F) and Combustible Liquids (flash point >140°F but <200°F).
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Q6.Gasoline is classified as:
A.Class 2.1 (Flammable Gas)B.Class 3 (Flammable Liquid)C.Class 4.1 (Flammable Solid)D.Class 9 (Miscellaneous)B. Class 3 (Flammable Liquid)Explanation: Gasoline is a liquid with a low flash point, making it a Class 3 Flammable Liquid.
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Q7.Which Hazard Class contains 'Flammable Solids'?
A.Class 2B.Class 3C.Class 4D.Class 5C. Class 4Explanation: Class 4 covers Flammable Solids (4.1), Spontaneously Combustible (4.2), and Dangerous When Wet (4.3).
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Q8.Materials that catch fire spontaneously upon contact with air are in which Division?
A.Division 4.1B.Division 4.2C.Division 4.3D.Division 5.1B. Division 4.2Explanation: Division 4.2 consists of Spontaneously Combustible materials (pyrophoric) that ignite without an external ignition source within 5 minutes of contact with air.
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Q9.Division 4.3 materials are dangerous when:
A.Exposed to airB.Exposed to heatC.WetD.CompressedC. WetExplanation: Division 4.3 is 'Dangerous When Wet'. These materials emit flammable or toxic gases upon contact with water.
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Q10.What is the primary hazard of Class 5 materials?
A.They are explosiveB.They yield oxygen, causing or enhancing the combustion of other materialsC.They are poisonousD.They are radioactiveB. They yield oxygen, causing or enhancing the combustion of other materialsExplanation: Class 5 (Oxidizers and Organic Peroxides) releases oxygen, which intensifies fires and can cause other materials to burn without air.
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Q11.Division 5.2 materials are known as:
A.OxidizersB.Organic PeroxidesC.Poison GasesD.Infectious SubstancesB. Organic PeroxidesExplanation: Division 5.2 contains Organic Peroxides, which are thermally unstable and may burn rapidly or explode.
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Q12.Class 6 materials are divided into Poison/Toxic (6.1) and:
A.Radioactive (6.2)B.Infectious Substances (6.2)C.Corrosive (6.2)D.Flammable Solid (6.2)B. Infectious Substances (6.2)Explanation: Class 6 is divided into 6.1 (Poison/Toxic materials) and 6.2 (Infectious Substances/Biohazards).
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Q13.Potassium Cyanide is an example of:
A.Division 6.1 (Poison)B.Class 8 (Corrosive)C.Class 9 (Miscellaneous)D.Division 2.3 (Poison Gas)A. Division 6.1 (Poison)Explanation: Potassium Cyanide is a toxic solid, falling under Division 6.1 Poison (Toxic) materials. (Division 2.3 is for gases).
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Q14.Hazard Class 7 includes:
A.CorrosivesB.Radioactive materialsC.Miscellaneous hazmatD.ExplosivesB. Radioactive materialsExplanation: Class 7 consists of Radioactive materials (e.g., Uranium, medical isotopes).
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Q15.What is the primary hazard of Class 8 materials?
A.They explode under pressureB.They burn skin and corrode metalC.They are radioactiveD.They are infectiousB. They burn skin and corrode metalExplanation: Class 8 Corrosives cause visible destruction or irreversible alterations to human skin or corrode metal (like aluminum/steel).
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Q16.Battery fluid (acid) is an example of:
A.Class 3B.Class 6.1C.Class 8D.Class 9C. Class 8Explanation: Battery acid is corrosive to skin and metal, placing it in Class 8.
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Q17.Class 9 materials are:
A.ExplosivesB.Miscellaneous hazardous materialsC.GasesD.RadioactiveB. Miscellaneous hazardous materialsExplanation: Class 9 covers Miscellaneous hazardous materials that present a hazard during transport but do not meet the definition of any other class (e.g., dry ice, lithium batteries, asbestos).
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Q18.Which Division includes 'Consumer Commodities' (ORM-D)?
A.Class 9B.Division 6.1C.It is a reclassification of certain materials for retail saleD.Class 1C. It is a reclassification of certain materials for retail saleExplanation: ORM-D (Other Regulated Material) is a reclassification for materials packaged for retail sale that pose limited hazard. (Note: ORM-D is being phased out for Limited Quantity, but still appears on some legacy exams).
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Q19.Division 2.3 covers:
A.Flammable GasesB.Non-Flammable GasesC.Poison GasesD.Tear GasC. Poison GasesExplanation: Division 2.3 is Poison Gas (e.g., Chlorine, Phosgene), known to be toxic to humans.
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Q20.Which of the following is considered a 'Combustible Liquid'?
A.A liquid with a flash point below 100°FB.A liquid with a flash point between 140°F (or 100°F depending on definition year) and 200°FC.A solid that burnsD.A gas that burnsB. A liquid with a flash point between 140°F (or 100°F depending on definition year) and 200°FExplanation: Combustible liquids have higher flash points (typically >140°F or >100°F in older regs, but <200°F) than Flammable Liquids. Diesel fuel is a common combustible liquid.
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Q21.Which division of explosives contains items with a 'minor explosion' hazard (e.g., consumer fireworks)?
A.1.1B.1.2C.1.3D.1.4D. 1.4Explanation: Division 1.4 consists of explosives that present a minor explosion hazard (e.g., small arms ammunition, consumer fireworks).
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Q22.A material that yields oxygen and causes combustion is a(n):
A.Flammable SolidB.OxidizerC.CorrosiveD.PoisonB. OxidizerExplanation: This is the definition of an Oxidizer (Division 5.1).
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Q23.Helium is classified as:
A.2.1 Flammable GasB.2.2 Non-Flammable GasC.2.3 Poison GasD.Class 9B. 2.2 Non-Flammable GasExplanation: Helium is an inert, non-flammable, non-poisonous compressed gas (Division 2.2).
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Q24.Division 6.2 'Infectious Substances' includes:
A.ArsenicB.Medical waste, virus cultures, and diagnostic specimensC.Battery acidD.Tear gasB. Medical waste, virus cultures, and diagnostic specimensExplanation: Division 6.2 includes materials known or reasonably expected to contain pathogens (bacteria, viruses, etc.).
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Q25.What is the difference between Division 1.1 and 1.2 explosives?
A.1.1 is Mass Explosion; 1.2 is Projection HazardB.1.1 is Fire Hazard; 1.2 is Mass ExplosionC.1.1 is Minor Hazard; 1.2 is Mass ExplosionD.There is no differenceA. 1.1 is Mass Explosion; 1.2 is Projection HazardExplanation: Division 1.1 has a mass explosion hazard (blast). Division 1.2 has a projection hazard (shrapnel/debris) but not a mass explosion hazard.
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Q26.Which class includes lithium batteries?
A.Class 8B.Class 3C.Class 9D.Class 4.1C. Class 9Explanation: Lithium batteries are classified as Class 9 Miscellaneous Hazardous Materials.
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Q27.What defines a 'Flammable Liquid' (Class 3)?
A.A liquid with a flash point of not more than 60°C (140°F)B.A liquid that burns at any temperatureC.A liquid with a flash point above 200°FD.A liquid that spontaneously combustsA. A liquid with a flash point of not more than 60°C (140°F)Explanation: The DOT defines a Flammable Liquid as one having a flash point of not more than 60°C (140°F).
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Q28.Division 1.3 explosives have a primary hazard of:
A.Mass explosionB.Fire and/or minor blast/projectionC.Toxic gasD.CorrosionB. Fire and/or minor blast/projectionExplanation: Division 1.3 explosives (like display fireworks) have a fire hazard and either a minor blast or minor projection hazard, but not a mass explosion hazard.
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Q29.Ammonium Nitrate is a common example of:
A.Division 1.1B.Division 5.1 OxidizerC.Class 8 CorrosiveD.Class 3 Flammable LiquidB. Division 5.1 OxidizerExplanation: Ammonium Nitrate is a powerful oxidizer (Division 5.1) used in fertilizers and explosives.
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Q30.Division 1.5 explosives are:
A.Very sensitiveB.Very insensitive substances with a mass explosion hazardC.Minor explosion hazardD.Not regulatedB. Very insensitive substances with a mass explosion hazardExplanation: Division 1.5 consists of Very Insensitive explosives (like blasting agents) that have a mass explosion hazard but are so insensitive that there is little probability of initiation during transport.
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Q31.Class 8 materials (Corrosives) can be:
A.Liquids onlyB.Solids onlyC.Liquids or SolidsD.Gases onlyC. Liquids or SolidsExplanation: Corrosives can be either liquids (like battery acid) or solids (like sodium hydroxide pellets).
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Q32.Dry Ice (Carbon Dioxide, solid) is classified as:
A.Class 2.2B.Class 3C.Class 4.1D.Class 9D. Class 9Explanation: Dry Ice is Class 9 (Miscellaneous) because it produces carbon dioxide gas which can displace oxygen in confined spaces.
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Q33.Which class is typically associated with the 'Spontaneously Combustible' placard?
A.4.2B.4.1C.4.3D.5.1A. 4.2Explanation: Division 4.2 is Spontaneously Combustible.
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Q34.An 'Inhalation Hazard' is most likely associated with:
A.Division 2.3 (Poison Gas) or Division 6.1 (Poison Liquid)B.Class 3C.Class 9D.Division 1.4A. Division 2.3 (Poison Gas) or Division 6.1 (Poison Liquid)Explanation: Materials that are toxic by inhalation fall under Division 2.3 (gases) or Division 6.1 (liquids meeting inhalation toxicity criteria).
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Q35.Division 1.6 explosives are:
A.Extremely insensitive articles with no mass explosion hazardB.Mass explosion hazardC.Projection hazardD.Fire hazardA. Extremely insensitive articles with no mass explosion hazardExplanation: Division 1.6 contains Extremely Insensitive Detonating Substances (EIDS) which demonstrate a negligible probability of accidental initiation or propagation.
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