RTO Hazardous Goods Test cheat sheet

Nine UN hazard classes: 1 explosives, 2 gases, 3 flammable liquids, 4 flammable solids/spontaneously combustible/dangerous when wet, 5 oxidizers and organic peroxides, 6 toxic and infectious substances, 7 radioactive, 8 corrosives, 9 miscellaneous.

Class is assigned by the substance's dominant hazard, not by its commercial use; a packing group (I great danger, II medium, III minor) is assigned within most classes to refine risk.

Division 4.1/4.2/4.3, 5.1/5.2, 6.1/6.2 and 2.1/2.2/2.3 split a class by hazard type; the division, not just the class, drives label and segregation decisions.

A substance is dangerous goods if it appears in the dangerous goods list by UN number, or meets the class definitions in the Model Regulations; a Safety Data Sheet section 14 states UN number, class, packing group.

UN numbers are four-digit identifiers (e.g. UN1203 petrol, UN1789 hydrochloric acid); a substance may carry a generic or N.O.S. entry when its specific name is not listed.

Flash point at or below 60 C closed cup generally makes a liquid flammable (Class 3); flammable liquids are further ranked by initial boiling point for packing group.

Transport category is a separate concept from packing group: it sets the quantity threshold that triggers full documentation and placarding, not the intrinsic hazard.

Environmentally hazardous substances (aquatic toxicity) fall in Class 9; lithium batteries are also Class 9 with special provisions governing state of charge and damage.

A substance with multiple hazards gets a primary class plus subsidiary risk labels; the primary class determines the orange placard number ordering.

Hazard labels are diamond-shaped, 100 x 100 mm minimum, with the class/division number in the bottom corner and the pictogram above; subsidiary labels show the subsidiary hazard.

Orange placards are at least 250 x 250 mm, mounted on the vehicle's two sides and rear; the upper half carries the hazard identification number, the lower half the UN number.

A hazard identification number (Kemler code) reads as a sequence: first digit is the primary hazard, second digit a subsidiary; a leading X means reaction with water is dangerous.

The UN number on a placard identifies the goods, while the hazard identification number describes the hazard; identical UN numbers can appear with different hazard identification numbers only when the substance is the same.

Elevated-temperature substances, environmentally hazardous marks (dead fish/tree), and lithium battery marks are separate markings, not hazard labels, and follow their own size and placement rules.

An elevated-temperature mark is required when a liquid is carried at or above 100 C, or a solid at or above 240 C.

Limited-quantity and excepted-quantity packages use a specific mark instead of full labels and placards; the mark must show the UN number for limited quantities.

Placards may be replaced by a single placard on the front and rear for certain small vehicles or when the total quantity carried stays below the placarding threshold.

The transport document must state: UN number, proper shipping name, class/division, packing group, number and kind of packages, total quantity, and consignor/consignee.

The proper shipping name must be the one in the dangerous goods list, including qualifying words in parentheses; trade names alone are not acceptable.

The emergency response telephone number must be monitored during transport and must be reachable; the number on the document is what responders use.

The shipper signs a declaration that the goods are fully and accurately described, correctly classified, packed, marked, and in proper condition for transport.

Additional entries are needed for: marine pollutant, elevated temperature, radioactive contents, and empty uncleaned packaging (which still requires the last contents' UN number).

A container/vehicle packing certificate accompanies the transport document for multimodal container loads and confirms packing and securing were done correctly.

Documents must be carried in the cab, not the cargo area, and remain legible; electronic documentation is acceptable where the jurisdiction permits it.

Retain shipping documents and the packing certificate for the period set by national law (commonly 3 months for the transport document).

Packing instructions are keyed to the UN number and packing group; the instruction number specifies the permitted packaging types and their performance level.

UN packaging is marked with a code: packaging type, performance level (X for I, Y for II, Z for III), and the specific gravity or pressure it was tested to.

Packing group I goods require X-rated packaging; Y-rated packaging may carry II and III; Z-rated packaging may carry III only - never a higher group than the rating.

Segregation rules prevent incompatible classes traveling together, e.g. oxidizers (5.1) away from flammables (3), acids away from cyanides, and Class 1 away from most other classes.

Inner packagings must be cushioned and secured so they cannot break or leak; absorbent material is required where the packaging instruction specifies it.

Combination packagings must be closed so that under normal transport conditions neither the inner nor outer packaging leaks.

Empty uncleaned packaging retains its hazard and must be closed, marked with its last contents, and carried under the same restrictions as the original goods.

Intermediate bulk containers (IBCs) and large packagings have their own instruction sets and periodic inspection requirements.

Load heavy packages at the bottom, secure every package against movement, and never load so that the vehicle exceeds its axle or gross weight limits.

Load incompatible classes apart: either in separate compartments, separated by a full compartment or bulkhead, or with a minimum separation distance where the rules allow.

Keep the load away from heat sources, direct sunlight, and the exhaust; Class 3 and 5 goods must not sit against a hot surface.

Use the parking brake, chocks, and a level surface during loading and unloading; the engine is off and no smoking or open flame is permitted.

The load must not obstruct the driver's view, the doors, the fire extinguisher, or the emergency exits.

Cylinders (Class 2) are carried upright, valve-protected, and secured so they cannot fall; never roll or drop them.

Before unloading, verify the goods match the transport document and check for leaks, damage, or shifted loads; record any discrepancy.

After unloading, close and secure the cargo area, and clean up any residue before the vehicle returns to general service.

Typical vehicle equipment: at least one fire extinguisher of the specified size, a wheel chock, a warning triangle, a spare wheel or repair kit, and personal protective equipment.

Fire extinguishers must be inspected and within their service date; the size and type follow national rules, commonly a dry powder unit rated for the goods carried.

Fire response differs by class: water on Class 3 liquid fires spreads it; use foam or dry powder; on Class 5 oxidizers, water in quantity is often the correct agent to cool and dilute.

Never fight a fire that reaches the cargo; withdraw upwind, keep clear, and let responders handle it.

In an incident: stop, secure the scene, warn other traffic, call emergency services, and give the UN number and proper shipping name from the transport document.

A spill kit with absorbent, containment, and PPE lets the driver contain a small leak; do not attempt to contain a large or reactive spill.

The driver must know the emergency response information carried with the documents and be able to read the hazard identification number to responders.

A fire in a tunnel or confined area is more dangerous: stop short of the tunnel where possible and do not enter a tunnel with a vehicle already on fire.

The driver needs a valid driving licence for the vehicle class plus a dangerous goods endorsement or ADR/vocational certificate where the jurisdiction requires it.

Training must cover the classes carried, documentation, labels and placards, loading and unloading, emergency response, and the driver's legal duties.

Refresher training is required periodically (commonly every 5 years) and after a change in the goods carried or a serious incident.

The certificate must be carried in the cab and shown to enforcement officers on request.

Fitness: no alcohol or impairing drugs; the driver must declare medical conditions and medications that affect alertness or reaction time.

Fatigue rules apply as for other freight: observe driving-time and rest limits and do not drive when unfit.

The driver is responsible for checking that the vehicle is fit for the load - brakes, tyres, fire extinguisher, and that the load is secured - before departure.

A driver who is not trained for a class must not carry it; the employer must not assign goods the driver is not certified to handle.

Tunnel restrictions are coded: categories A to E progressively restrict more goods; a Category E tunnel bans most dangerous goods, while A restricts only the most severe.

Each goods entry in the dangerous goods list carries a tunnel restriction code that tells the driver which tunnel categories may be used.

In urban areas, follow designated dangerous goods routes; do not use residential streets, pedestrian zones, or underpasses unless permitted.

Parking: park in a secure area away from dwellings, crowds, and ignition sources; never leave a loaded vehicle unattended in a public place.

When parking is unavoidable, apply the parking brake, chock the wheels, and keep the vehicle visible and ventilated where the rules require it.

Some goods (e.g. Class 1 and 7) require prior notification or escort on certain routes; check the national competent authority's requirements.

Bridges, ferries, and tunnels may have weight, height, or quantity limits; verify the permitted quantity before entering.

Keep the transport document and emergency number available so that a tunnel or bridge operator can verify the load on request.

Reportable incidents include a spill, leak, fire, uncontrolled release, or any event requiring emergency services or roadside assistance.

The report must include the UN number, proper shipping name, quantity released, location, and any injuries; give it to responders and to the employer.

Contain small spills with absorbent and dikes; keep ignition sources away, stay upwind, and do not wash the spill into drains or waterways.

Do not re-enter a contaminated area or attempt cleanup beyond your training; responders or a hazmat team handle significant releases.

Keep an incident record: what was carried, what happened, who was notified, and what corrective action was taken.

Retain transport documents, training certificates, inspection records, and incident reports for the period set by national law.

The employer must investigate incidents and near misses and update procedures and training accordingly.

Notify the consignor and consignee of any damage or loss, and record the discrepancy on the delivery paperwork.