Transportation of Dangerous Goods common mistakes
Transportation of Dangerous Goods · Understand the traps and how to avoid them.
Selecting the wrong UN number or proper shipping name for a substance by relying on a trade name or common name instead of the dangerous goods list, and not checking the hazard class and packing group together.
Candidates often memorize a few common substances and then try to map a new product to a familiar entry without verifying the full entry, or they assume the first name they recognize is correct. They may also ignore that the same UN number can appear with different packing groups depending on the substance's properties.
What to do instead
Always look up the substance in the dangerous goods list by its chemical or technical name, confirm the UN number, proper shipping name, class, and packing group as a single set, and cross-check any synonyms or trade names against the list. Practice with substances that have multiple entries, such as alcohols or paints, so you see how the list distinguishes them.
Using a shipping paper that lacks required elements such as the emergency response telephone number, the shipper's certification statement, or the correct sequence of basic description elements, and not recognizing that the basic description must appear in a specific order.
Candidates often focus on the substance entry and overlook the administrative and formatting requirements of the shipping paper. They may also confuse the order of the basic description (UN number, proper shipping name, class, packing group) and place the class before the name, or forget that the emergency contact must be a person or agency that can provide information during an incident.
What to do instead
Memorize the required sequence of the basic description and the additional entries (total quantity, number and type of packages, shipper's certification, emergency response phone number). Practice filling out a shipping paper for several different loads, then check it against the regulatory checklist. Note that the emergency number must be monitored at all times and must not be a voicemail or a number that only provides general information.
Applying the wrong placard or label to a package or vehicle because the candidate confuses the hazard class number with the placard design, or uses a label where a placard is required (or vice versa), and fails to check the placard specification (size, color, text).
The visual similarity between some labels and placards leads candidates to assume they are interchangeable. Candidates may also forget that the placard must show the hazard class number at the bottom, or that some classes have specific text (e.g., 'FLAMMABLE' or 'OXIDIZER') and that the placard must be durable and meet size requirements.
What to do instead
Study the placard and label charts side by side, noting that placards are larger and must display the class number, while labels are smaller and may not. Practice matching each hazard class to its placard, including the text and color, and remember that subsidiary hazards use labels on packages but may require subsidiary placards only in specific cases. Verify the placard meets the required dimensions and is affixed to the correct location on the vehicle.
Assuming that any container that holds dangerous goods is acceptable, without verifying that the packaging is UN specification, marked with the correct UN packaging code, and suitable for the substance's packing group and special provisions.
Candidates often think that as long as the container does not leak, it is fine. They may not realize that packaging must be tested and marked, that the UN packaging code indicates the type of packaging and the packing group it is authorized for, and that some substances have special packaging provisions (e.g., venting, lining, or limited quantity exceptions).
What to do instead
Learn to read the UN packaging mark: the UN symbol, packaging identification code, packing group letter, and the year of manufacture. Practice determining whether a given packaging is authorized for a specific substance by checking the packing group and any special provisions in the dangerous goods list. Remember that inner packaging and outer packaging must be compatible and that the packaging must be in good condition before each use.
Loading dangerous goods without checking segregation requirements, and securing packages so that they cannot shift, using inappropriate blocking or bracing, or loading incompatible goods together because the candidate relies on general loading experience rather than the segregation table.
Candidates may not be familiar with the segregation table and may assume that all dangerous goods can be loaded together as long as they are separated by distance. They may also overlook that some goods must be segregated by a full compartment or that certain goods require special stowage (e.g., away from heat sources). In addition, candidates may not understand that securing must prevent movement in all directions and that the method must be appropriate for the package type.
What to do instead
Study the segregation table and the specific segregation requirements for each class. Practice with scenarios where two substances must be separated by a barrier or a certain distance. For securing, learn the principles of blocking, bracing, and tie-down, and remember that the goal is to prevent shifting, tipping, and falling. Review the requirements for mixed loads and ensure that the segregation rules are applied before loading begins.
Failing to recognize when an incident must be reported, underreporting because the candidate thinks a small release is not reportable, or reporting to the wrong agency and within the wrong timeframe.
Candidates often confuse the reporting thresholds and may not know that a release of a hazardous substance above the reportable quantity must be reported immediately to the appropriate authority. They may also think that only large spills are reportable, or they may not know the difference between immediate notification and written follow-up reports.
What to do instead
Memorize the reporting criteria: a release of a hazardous substance equal to or greater than the reportable quantity, a fire, an emergency involving a vehicle, or any situation that requires immediate action. Learn the immediate notification requirements (who to call, what information to provide) and the follow-up written report deadlines. Practice with scenarios to determine if an incident is reportable and which agency to notify.
Believing that training is a one-time event and that a certificate never expires, or failing to provide function-specific training for each employee's role, and not maintaining training records for the required period.
Candidates may think that general awareness training is sufficient and that refresher training is optional. They may also not realize that training must be repeated at least every three years (or sooner if regulations change) and that records must be kept for as long as the employee is employed and for a certain period afterward. In addition, they may not understand that training must cover the specific functions the employee performs.
What to do instead
Learn the training requirements: general awareness, function-specific, safety, and security awareness training. Know the refresher cycle (typically every three years) and the recordkeeping requirements (e.g., keep records for two years after employment ends). Practice identifying the training needed for different job roles, such as a loader versus a driver, and review the elements that must be included in a training record.
Applying an exemption or special provision incorrectly, such as assuming that a limited quantity or excepted quantity exception applies to all dangerous goods, or using an exemption without meeting its conditions (e.g., packaging, marking, documentation).
Candidates may see the word 'exemption' and assume it means the goods are completely unregulated. They may not read the specific conditions, such as maximum quantity per package, packaging requirements, or the need to carry documentation. They may also confuse limited quantity with excepted quantity and apply the wrong marking or documentation relief.
What to do instead
Study the specific exemptions and special provisions in the regulations, noting the exact conditions that must be met. For limited quantities, learn the maximum inner packaging limits and the marking requirements (e.g., the limited quantity mark). For excepted quantities, learn the different categories and their packaging and documentation requirements. Practice with scenarios to determine if an exemption applies and what conditions must be satisfied.
Misclassifying a substance by assigning a hazard class based solely on one property (e.g., flammability) without considering subsidiary hazards, or by ignoring the precedence of hazard rules when a substance has multiple hazards.
Candidates may not know that many substances have multiple hazards and that the classification must reflect the primary hazard and any subsidiary hazards. They may also not be familiar with the precedence of hazard table, which determines the primary class when a substance meets the criteria for more than one class. This leads to incorrect labels, placards, and documentation.
What to do instead
Learn the hazard classes and the criteria for each, including the tests or properties that define them. Study the precedence of hazard table and practice applying it to substances with multiple hazards, such as a flammable liquid that is also toxic. Remember that the primary hazard determines the class for documentation and placarding, but subsidiary hazards must be indicated on labels and may affect packaging and segregation.
Ignoring the requirement to provide and use emergency response information (such as the emergency response guidebook or a equivalent document) during transport, or not knowing how to use it to determine initial isolation and protective action distances.
Candidates may think that the shipping paper is enough and that emergency response information is only for the driver. They may also not be familiar with the structure of the emergency response guidebook and how to find the guide number for a substance, or they may not understand that the guide number is different from the UN number and that it provides specific response actions.
What to do instead
Learn how to use the emergency response guidebook: look up the substance by UN number or name, find the guide number, and read the potential hazards, public safety, and emergency response sections. Practice determining initial isolation and protective action distances for different substances and quantities. Remember that the emergency response information must be carried on the vehicle and must be immediately available to the driver and emergency responders.