CDL Hazardous Materials Endorsement (HME) flashcards

When loading cargo tanks with Class 3 Flammable Liquids, the initial flow rate must be restricted to prevent hazardous static electricity buildup.

• Applies to Class 3 Flammable Liquids.
• Restricted flow prevents static discharge.
• Crucial for preventing ignition during filling.

Memory trick: Static Sparks Danger, Slow Start Safely.

Division 6.1 (Poisonous) materials must be segregated from foodstuffs, feed, or edible materials by a solid, leak-proof barrier from floor to ceiling.

• Applies to Division 6.1 Poisonous materials.
• Protects foodstuffs from contamination.
• Requires a physical, leak-proof barrier.

Memory trick: Food & Poison: Barrier Between, Safe & Sound.

Vehicles transporting hazardous materials listed in Table 2 must be placarded with the appropriate specific placards if the aggregate gross weight of all Table 2 hazardous materials on board is 1,001 pounds or more.

• Applies to hazardous materials in Table 2.
• Threshold is 1,001 pounds aggregate gross weight.
• Requires specific placards for each hazard class if threshold met.

Memory trick: Table 1, always; Table 2, check the thousand pounds.

For bulk shipments (e.g., cargo tanks, portable tanks, or freight containers with a capacity of 640 cubic feet or more) of a single hazardous material listed in Table 1, the vehicle must display the specific placard for that material's hazard class.

• Applies to bulk quantities.
• For Table 1 hazardous materials.
• Specific hazard class placard required.

Memory trick: Placards tell the tale: What's inside, what's its peril.

Federal regulations limit the time a driver can leave a cargo tank containing UN1005, Anhydrous Ammonia, unattended to a maximum of 5 minutes before specific parking attendance requirements must be met.

• Applies to UN1005 Anhydrous Ammonia.
• Cargo tank vehicles.
• Max 5 minutes unattended without specific attendance measures.

Memory trick: Five minutes, Anhydrous Ammonia, don't leave it!

Drivers operating cargo tanks equipped with emergency discharge control systems for hazardous materials must ensure the system is operational and be fully trained in its proper use to prevent or control spills.

• Applies to specific cargo tanks (e.g., flammable liquids).
• Driver must verify operational status.
• Driver must know how to use the system.

Memory trick: Emergency controls: Know it, Check it, Use it.

The required number and type of attachments on a portable tank to ensure safe lifting when carrying hazardous materials.

• Minimum of four lifting devices.
• Must be securely attached to the tank structure.
• Ensures stability and prevents damage during handling.

Memory trick: Lift a tank, four hooks are key, for stability and safety!

A thorough examination of a portable tank before loading hazardous materials to ensure it meets safety and regulatory requirements.

• Includes checking for structural integrity, leaks, and proper markings.
• Data plate presence and legibility are critical.
• Ensures the tank is fit for continued safe service.

Memory trick: Inspect the tank, find the flaw, follow the hazmat law!

Portable tanks used for hazardous materials must have specific permanent markings, including specification, capacity, and inspection/test dates, to ensure compliance and safety.

• Required by 49 CFR 178.274.
• Includes owner's name, serial number, and capacity.
• Crucially includes date of last periodic inspection and test.

Memory trick: A portable tank's permanent marks are like its ID card: who owns it, what it is, and when it was last checked.

To determine the maximum allowable weight of a hazardous liquid in a bulk tank, calculate the tank's water capacity, adjust for the material's specific gravity, and then apply the maximum filling density.

• Weight of water = Volume × 8.34 lbs/gallon.
• Weight of material (full) = Weight of water × Specific Gravity.
• Maximum load weight = Weight of material (full) × Filling Density.

Memory trick: Water's weight is your start, Specific Gravity adjusts, then Filling Density is your final cut.

For liquids, 'bulk packaging' refers to a container with a maximum capacity greater than 450 liters (119 gallons), where hazardous materials are loaded without intermediate containment.

• Capacity > 450 L (119 gallons) for liquids.
• Capacity > 450 L or net mass > 400 kg for solids.
• Water capacity > 454 kg for gases.
• Includes cargo tanks, portable tanks, IBCs, freight containers.

Memory trick: Think of the '119-gallon line': cross it, and your package becomes 'BULK,' triggering bigger rules.

A safety valve located inside a cargo tank, designed to automatically close and prevent the release of hazardous material from below-liquid-level openings if external piping or fittings are damaged.

• Located inside the tank.
• Self-closing mechanism.
• Prevents uncontrolled release during external damage.
• Required for liquid hazardous materials.

Memory trick: Safety valves: Stop the flow, prevent the blow, relieve the pressure, and measure the level.

UN portable tank specifications (e.g., T11, T50, T75) define the design, construction, and testing requirements for tanks used in international and domestic transport of various hazardous materials, including liquids and gases.

• UN T11: General purpose liquids, moderate hazard.
• UN T50: Non-refrigerated liquefied compressed gases.
• UN T75: Refrigerated liquefied gases.
• Test pressure is a key differentiator for tank types.

Memory trick: The 'T' in UN Tanks means 'Type' for specific hazmat: T11 for liquids, T50 for non-refrigerated gases, T75 for cold gases.

An IBC is a rigid or flexible portable packaging, other than a cylinder or portable tank, designed for mechanical handling, with a maximum capacity for solids not exceeding 3,000 kg (6,614 lbs) or 3 cubic meters (793 gallons) for liquids/solids.

• Designed for mechanical handling.
• Capacity up to 3,000 kg or 3,000 liters.
• Used for various hazardous materials.

Memory trick: Cargo, Portable, Intermediate: The three big P's of hazmat hauling.

The maximum internal pressure a DOT Specification 406 cargo tank is designed to safely withstand during normal transport operations.

• Rated for 2.65 psig (pounds per square inch gauge).
• Used for non-pressure liquids, such as gasoline or fuel oil.
• Designed with elliptical cross-sections for low-pressure liquids.

Memory trick: Four-oh-six, for low-pressure fix, 2.65, that's the mix!

The maximum amount of hazardous material that can be loaded into a portable tank, determined by the tank's water capacity, the material's specific gravity, and its maximum filling density.

• Ensures adequate outage/ullage for expansion.
• Prevents over-pressurization due to temperature changes.
• Based on material properties and tank design.

Memory trick: Fill 'er up, but not too far, specific gravity sets the bar!

Emergency internal self-closing stop valves are safety devices located inside a cargo tank, designed to automatically close and prevent hazardous liquid discharge in case of external valve damage or other emergencies.

• Located inside the tank shell.
• Self-closing mechanism.
• Often remotely operated.
• Critical for preventing spills during accidents.

Memory trick: For a liquid tank, the 'Internal Valve' is like a hidden bodyguard, stopping leaks from the inside out.

Hazardous materials listed in Table 1 of 49 CFR 172.504 require placards on bulk packaging regardless of the aggregate gross weight of the material.

• Always placard bulk Table 1 materials.
• Table 1 includes explosives, poisons, radioactive materials, and some flammable gases.
• Table 2 materials have a 1,001 lb threshold for placarding.

Memory trick: Always check the HAZMAT table first; Table 1 means placard ALL bulk, Table 2 has a weight rule.

For domestic transportation by highway or rail, a Class 9 (Miscellaneous Hazardous Material) placard is not required for bulk packaging, although the identification number must still be displayed.

• Applies only to Class 9 materials.
• Specific to domestic highway and rail transport.
• Identification numbers are still required on bulk packaging.
• International or vessel/air transport may require placards.

Memory trick: Class 9 on a truck or train? No placard pain! But the ID number still remains.

For hazardous materials listed in Hazardous Materials Table 2, placards are required on a transport vehicle when the aggregate gross weight of these materials is 1,001 pounds (454 kg) or more.

• Applies to most common hazardous materials.
• Threshold is 1,001 pounds.
• Does not apply to Table 1 materials.

Memory trick: Two Tables, Two Rules: Table 1, always; Table 2, a thousand pounds.

DOT specifications for cargo tanks classify them by design pressure, material, and construction for specific hazardous materials, ensuring safe transport.

• DOT 406: Non-pressure, <25 psig MAWP, flammable liquids.
• DOT 407: Low-pressure, 25-40 psig MAWP, flammable/corrosive liquids.
• DOT 412: High-pressure, 15-25 psig MAWP (or higher), corrosive liquids.
• DOT 331: Pressure tanks for compressed gases, >100 psig MAWP.

Memory trick: The DOT numbers tell you the tank's pressure limits: '6' for low, '7' for medium, '12' for corrosive, and '31' for high pressure gases.

A flammable liquid is a liquid having a flash point of not more than 140°F (60°C), as defined by DOT hazardous materials regulations (49 CFR 173.120).

• Flash point <= 140°F (60°C).
• Includes some liquid mixtures with flammable components.
• Ignites easily at ambient temperatures.

Memory trick: If it's a liquid and flashes below sixty Celsius (140 F), it's a 'Class 3' fiery liquid.

A bulk packaging that is permanently attached to or forms a part of a motor vehicle or is an integral part of a trailer.

• Loaded/unloaded while attached to the vehicle.
• Commonly used for liquids and compressed gases.
• Subject to specific DOT specifications (e.g., MC306, DOT406).

Memory trick: Bulk's the deal, on a truck or wheel, know its feel!

Federal regulations prohibit parking vehicles carrying Division 2.1 (Flammable Gas) within 300 feet of specific structures like bridges, tunnels, or buildings where people might gather.

• Applies to Division 2.1 (Flammable Gas) and Class 1 (Explosives) materials.
• Prohibited within 300 feet of a bridge, tunnel, or dam.
• Prohibited within 300 feet of a place where people gather (e.g., residence, restaurant, store).
• These rules aim to minimize risk to the public in case of an incident.

Memory trick: No bridges, no tunnels, no buildings, no busts.

A liquid that has a flash point at or above 100°F (37.8°C) and below 200°F (93°C).

• Flash point between 100°F and 200°F
• Can ignite under specific conditions
• Less volatile than flammable liquids

Memory trick: Flash points dictate if it's hot enough to ignite.

Internal self-closing stop valves on cargo tanks carrying non-pressure liquid hazardous materials must be designed to close automatically via thermal, remote control, or excess flow systems.

• Mandated for non-pressure liquid hazmat.
• Protects against spills during incidents.
• Thermal, remote, and excess flow are key systems.

Memory trick: TRaCE your steps to safety: Thermal, Remote, Excess.

If a vehicle carries multiple hazardous materials from the same hazard class (not from Table 1) and their combined weight exceeds 1,001 pounds, the vehicle must display the specific placard for that hazard class.

• Applies to materials listed in Placarding Table 2.
• If multiple materials belong to the same hazard class.
• Aggregate gross weight of that class exceeds 1,001 pounds.
• Display the specific placard for that single hazard class (e.g., CORROSIVE, FLAMMABLE).

Memory trick: Total up the same, then placard the name.

Certain hazardous materials, like non-flammable, non-poisonous gases (Class 2.2) and corrosive materials (Class 8), do not require segregation from each other during transport.

• Segregation prevents dangerous reactions between incompatible materials.
• Class 2.2 includes gases like compressed air, nitrogen, helium.
• Class 8 includes acids and bases.
• The segregation table (49 CFR 177.848) dictates compatibility.

Memory trick: Incompatibility is key, check the segregation table to prevent disaster.

When transporting a bulk quantity of a hazardous material, the specific placard corresponding to its primary hazard class is always required, regardless of weight thresholds for non-bulk packages.

• Bulk packaging includes cargo tanks, portable tanks, rail tank cars, etc.
• Specific placard required for the primary hazard class.
• Table 1 materials always require their specific placard.
• Table 2 materials in bulk also require their specific placard.

Memory trick: Bulk means specific, no 'dangerous' fakes, show the real class for safety's sakes.

The UN portable tank identification plate provides essential technical and certification information about the tank, such as capacity, pressures, and test dates, but not emergency contact details.

• Technical specifications of the tank.
• Manufacturing and testing data.
• Does NOT include emergency contact info.

Memory trick: The plate tells tank's specs, not who to call.

For N.O.S. hazardous materials in bulk packagings, the technical name(s) of the hazardous components must be displayed on the packaging.

• Applies to N.O.S. entries in bulk packaging (e.g., portable tanks, cargo tanks).
• Technical name(s) must be in parentheses.
• Provides more specific identification than the N.O.S. entry alone.

Memory trick: N.O.S. means need more specifics, technical name's the key.

The initial filling rate for flammable liquids into a cargo tank must not exceed 3 feet per second until the fill pipe opening is submerged to prevent static electricity buildup.

• Static electricity can be generated by liquid flow.
• Flammable liquids produce ignitable vapors.
• A slow initial fill rate minimizes static discharge risk.

Memory trick: Slow 'pour' for 'flammable' liquids, 'three' feet is the 'rule'.

To prevent overfilling and account for thermal expansion, bulk tanks carrying hazardous liquids often have a maximum allowable fill percentage of their volumetric capacity, typically 95%.

• Prevents dangerous over-pressurization.
• Accounts for temperature changes.
• Calculated as a percentage of total volume.

Memory trick: Percentage times total equals the safe fill line.

Loading or unloading of any hazardous material from a cargo tank requires continuous attendance by a qualified person who must remain within 25 feet and in clear view of the tank.

• Applies to all hazard classes in cargo tanks.
• Ensures immediate response to any incident.
• Prevents unauthorized access or tampering.

Memory trick: Cargo tanks: 'Always watch', 'always near', 'no breaks'.

When the aggregate gross weight of two or more non-bulk Table 2 hazardous materials exceeds 1,001 pounds, specific placards for each hazard class are required, unless the DANGEROUS placard option is chosen.

• Table 2 materials include many common hazardous materials.
• Aggregate threshold for placarding is 1,001 pounds.
• If threshold met, specific placards (e.g., FLAMMABLE, CORROSIVE) are required.
• DANGEROUS placard is an *option* for mixed Table 2 loads, not a mandatory requirement over specific placards.

Memory trick: Over a grand, specific placards stand, unless DANGEROUS is at hand.

If a vehicle contains two or more hazardous materials of different hazard classes, and their aggregate gross weight exceeds 1,001 pounds, a 'DANGEROUS' placard is required.

• Applies to mixed loads with different hazard classes.
• Individual materials must be below their specific placarding thresholds.
• Total aggregate weight must exceed 1,001 pounds.

Memory trick: Different classes, over a grand, 'DANGEROUS' placard for the land.

If all hazardous materials on a vehicle belong to the same hazard class and their total weight exceeds 1,001 pounds, the vehicle must be placarded for that specific hazard class.

• Applies when multiple materials are in the same hazard class.
• Aggregate gross weight must exceed 1,001 pounds.
• Specific placard for that hazard class is required (e.g., 'CORROSIVE').

Memory trick: Same class, over a grand, placard the whole land.

A shear section in a cargo tank's internal stop valve is a weakened point designed to break cleanly upon impact or stress to external piping, ensuring the valve remains closed and prevents product release.

• Protects against external piping damage.
• Ensures valve integrity in accidents.
• A crucial safety feature for liquid hazmat.

Memory trick: Shear it off to keep the valve sealed tight.

For minor hazardous materials incidents (e.g., small, contained spills with no injuries or public danger) that do not meet federal immediate reporting thresholds, the driver's primary responsibility is to report the incident to their carrier (employer).

• Federal reporting thresholds are specific.
• Immediate NRC call for serious incidents.
• 30-day written report for less severe but significant incidents.
• All incidents, even minor, should be reported to the carrier/employer.

Memory trick: Report to carrier first, then federal rules are discussed.

Drivers transporting Division 2.3 (Poison Gas) in cargo tanks or portable tanks must carry a self-contained breathing apparatus (SCBA) in the vehicle, readily available and in good working order.

• Applies to Division 2.3 (Poison Gas).
• Specifically for cargo tank motor vehicles or portable tanks.
• SCBA must be readily available.
• SCBA must be in good working order.

Memory trick: Poison gas means SCBA on hand, ready to breathe, understand.

The primary factor in determining the maximum amount of a hazardous material that can be loaded into a bulk tank is its volumetric capacity, which dictates the total space available.

• Volume is the physical constraint.
• Specific gravity converts volume to weight.
• Weight limits are often derived from volume.

Memory trick: Volume first, then density to get the weight right.

Compressed gas cylinders must be securely restrained against movement (rolling, falling, or shifting) in any direction during transport, whether they are loaded horizontally or vertically.

• Cylinders are heavy and can cause significant damage if unsecured.
• Proper securement prevents impact damage to valves and cylinders.
• Orientation (horizontal/vertical) is less critical than the securement itself.

Memory trick: Cylinders need to be 'snug', horizontal or vertical, just 'don't move'.

Placarded vehicles must adhere to specific parking rules, including prohibitions against parking near traveled roadways, bridges, tunnels, open flames, and occupied buildings, while designated, safe parking areas are permissible.

• No parking within 5 feet of traveled portion of public street/highway.
• No parking within 300 feet of a bridge, tunnel, or dwelling (for certain materials/quantities).
• No parking near open flames or fires.
• Designated truck stop parking, away from hazards, is generally acceptable.

Memory trick: No roads, no fires, no tunnels, no homes – keep hazmat alone.

For N.O.S. (Not Otherwise Specified) hazardous materials, the technical name(s) of the hazardous components must be included in parentheses on both the shipping paper and the package.

• Applies to both bulk and non-bulk N.O.S. packages.
• Technical name(s) clarify the specific hazardous components.
• Essential for detailed identification beyond the general N.O.S. description.

Memory trick: N.O.S. means 'Need Our Specifics', technical name clarifies.

During loading/unloading flammable gases, avoid any activities that could create an ignition source, such as operating unapproved electronic devices or smoking, within a specified distance.

• Flammable gases are easily ignited.
• Electronic devices can generate sparks or RF energy.
• A 25-foot safety zone is often required around flammable cargo tanks.

Memory trick: No sparks near flammable tanks, keep electronics away.

A bulk packaging, other than an IBC, portable tank, or cargo tank, designed for mechanical handling, with a capacity of more than 450 liters for liquids or 400 kg for solids.

• Capacity > 450 liters (liquids) or > 400 kg (solids).
• Designed for mechanical handling.
• Distinct from IBCs, portable tanks, and cargo tanks.

Memory trick: Large Packagings are the 'other' big boxes, not IBCs.

For most placarded vehicles (excluding certain explosives), 'attended' means the driver is within 100 feet of the vehicle and has it within their unobstructed view, or the vehicle is in an approved safe haven.

• Applies to most placarded vehicles carrying hazardous materials.
• Driver must be within 100 feet.
• Driver must have an unobstructed view of the vehicle.
• Alternatively, vehicle can be in an approved safe haven.

Memory trick: 100 feet, clear sight: that's how you attend a placarded truck.

Bulk packagings, including cargo tanks, must display appropriate placards on all four sides: front, rear, and both sides, to ensure visibility from any approach.

• Required for hazardous materials.
• Ensures visibility for emergency responders.
• Applies to cargo tanks, portable tanks, IBCs (if bulk placarded).

Memory trick: Four sides to show, so everyone knows.

Portable tanks with a capacity of 1,000 gallons or more must be secured to the vehicle with a minimum of four tiedowns.

• Tiedowns prevent shifting and overturning during transport.
• The number of tiedowns depends on tank capacity and weight.
• Minimums are specified in 49 CFR 177.834.

Memory trick: Big tank, 'four' strong ties to stay put.

For UN portable tanks, the Maximum Allowable Working Pressure (MAWP) is generally established as two-thirds (2/3) of the minimum test pressure to ensure a safety margin.

• MAWP = 2/3 * Test Pressure.
• Test pressure is always higher than MAWP.
• Ensures structural integrity under operating conditions.

Memory trick: MAWP is two-thirds safe, tested at full force.

Spontaneously Combustible materials (Class 4.2) must be kept separate from other hazard classes, especially oxidizers, to prevent dangerous chemical reactions during transport.

• Class 4.2 materials can ignite without an external ignition source.
• Oxidizers (Class 5.1) provide oxygen, which can fuel or initiate combustion.
• Segregation prevents accidental reactions leading to fire or explosion.

Memory trick: Spontaneous combustion 'oxidizes' safety if they're together.

Shipping papers for hazardous materials must remain immediately accessible to the driver and emergency responders for as long as the material is on the vehicle, even if delivery is refused or delayed.

• Hazmat is 'in transport' until properly offloaded or returned.
• Immediate accessibility rule still applies.
• Crucial for emergency response during unforeseen delays or returns.

Memory trick: Papers stay near, while hazmat is here.

A mandatory marking on Intermediate Bulk Containers (IBCs) indicating compliance with design and testing standards for hazardous materials.

• Required for all certified IBCs.
• Includes design type, max gross mass, date of manufacture, etc.
• Ensures the IBC meets safety standards for hazmat transport.

Memory trick: IBC: ID, Name, and Cert Plate, makes hazmat transport safe and great.

Any difference between the information on hazardous materials shipping papers and the actual contents or conditions of the shipment.

• Driver must verify accuracy before transport.
• Discrepancies must be resolved with the shipper.
• Safety and regulatory compliance depend on accurate papers.

Memory trick: Verify, flag, and call, before you haul.

Emergency discharge control systems on cargo tanks for certain hazardous materials (like flammable gases) must be readily activatable by the driver via remote, manual, or in-cab devices, without requiring specialized, non-readily available tools.

• Mandatory for cargo tanks carrying certain flammable gases and liquids.
• Designed for rapid activation in an emergency.
• Acceptable methods include remote, manual (on tank), and in-cab controls.
• Requires no specialized tools or keys not readily available to the driver.

Memory trick: Quick stop, easy access: emergency discharge must flow.

Cargo tanks transporting liquid hazardous materials with a vapor pressure exceeding 14.7 psia at 100°F must have a minimum MAWP of 35 psi, or the vapor pressure of the material at 115°F, whichever is greater.

• Applies to liquids with vapor pressure > 14.7 psia @ 100°F.
• Minimum MAWP is 35 psi.
• Or vapor pressure @ 115°F, if higher.
• Ensures tank integrity under thermal expansion.

Memory trick: High vapor pressure means 35 PSI or more, for sure.

Division 6.1 (Poisonous) materials are generally prohibited from transport with foodstuffs, but an exception exists if the poison is in an overpack and separated by a physical barrier.

• Prevents contamination of food by toxic substances.
• Overpacking provides an additional layer of protection.
• A physical barrier ensures separation and prevents contact.

Memory trick: Poisons and food: 'Overpack' and 'barrier' or 'no share'.

The requirement to display the UN or NA identification number on non-bulk packages containing hazardous materials.

• Mandatory on each non-bulk package.
• Must be preceded by 'UN' or 'NA'.
• Aids in rapid identification of contents.

Memory trick: UN number, label bright, keeps hazmat in plain sight.

A hazardous materials cargo tank carrying certain flammable gases or liquids is considered 'attended' when the driver is within a specific distance and has an unobstructed view of the vehicle.

• Required for cargo tanks containing Division 2.1 (flammable gas) or Class 3 (flammable liquid) materials.
• Driver must be within 50 feet of the vehicle.
• Driver must maintain an unobstructed view of the vehicle.
• Ensures immediate intervention in case of a leak or other incident.

Memory trick: Fifty feet, clear sight, safe night.

Division 1.3 explosives exceeding 5,000 lbs aggregate gross weight require adherence to specific hazardous materials routes and potentially special permits.

• Division 1.3 explosives have a fire hazard with minor blast effects.
• Weight limits are set to manage risk on public roads.
• Exceeding the limit triggers more restrictive transport regulations.

Memory trick: Explosives need special 'routes' if they're too 'heavy'.