What precautions should be taken when transporting hazardous chemicals? How should emergency response be handled?

The transportation of dangerous goods is a specialized form of transport. Generally, only entities that have undergone rigorous review by the relevant national authorities and possess the requisite facilities and equipment to ensure the safe carriage of hazardous materials are authorized to engage in such transportation.

Precisely because hazardous materials are flammable, explosive, and highly corrosive, their transportation poses significant risks. If such materials are transported improperly or if an accident occurs en route, it could result in severe consequences for nearby vehicles, personnel, and the environment.

What precautions should be taken to ensure safe driving of hazardous‑material transport vehicles?

What are the requirements for emergency response?

I. Five Essential Pre-Ride Checks

01 Verify that the vehicle license plate is securely mounted, that the safety inspection sticker and insurance sticker are properly displayed, and that the vehicle registration certificate, road transport permit, and road transport pass for highly toxic chemicals are all present, valid, and carried on board.

02 Are the vehicle’s marker lights, signage, reflective markings, side and rear protective devices, fire extinguishers, and other safety equipment in good working order, and is the satellite positioning system functioning properly?

03 Are the vehicle’s braking, lighting, steering, and other safety systems in compliance with operational requirements, and are the tire specifications compliant and wear within normal limits?

04 Verify that the emergency shut-off device on tank trucks transporting liquid hazardous goods is properly installed and in the closed position.

05 Verify that the driver’s license, as well as the professional qualification certificates for the driver and the escort, are complete, valid, and carried on one’s person.

II. Five Safety Tips for Driving

01 Choose a reasonable route with favorable traffic conditions, stay away from towns and residential areas, and do not enter areas where vehicles transporting hazardous materials are prohibited. Vehicles transporting highly toxic chemicals must follow the time and route approved by the public security authorities and may not alter them arbitrarily.

02 Maintain a safe driving speed; under no circumstances should your speed exceed 80 km/h. In low-visibility conditions such as nighttime, rain, fog, or icy and snowy weather, reduce your speed.

03 Maintain a reasonable following distance from the vehicle ahead, and increase the gap in adverse weather conditions such as rain, fog, or icy/snowy roads.

04 Do not change lanes arbitrarily while driving; on highways, stay in the designated lanes.

05 Drivers must stay alert; after driving for approximately two hours, they should pull over to rest and promptly inspect the vehicle’s technical condition, ensuring that the emergency shut-off valve remains closed.

III. Five Key Points for Loading and Unloading Cargo

01 Enterprises, vehicles, drivers, escorts, and loaders/unloaders engaged in the transport of dangerous goods must obtain the corresponding qualifications.

02 The loaded medium is consistent with the spraying medium of the tank and the medium specified on the vehicle’s road transport permit.

03 Hazardous goods must be loaded evenly and symmetrically, securely fastened as a whole, with one type of cargo per vehicle. Different hazardous materials must not be mixed, and overloading is prohibited.

04 After dangerous goods are loaded, the name, shape, quantity, disposal method, and the enterprise’s contact information must be recorded in writing and carried on board.

05 After loading is complete, the emergency shut-off valve of the liquid hazardous cargo tank car shall be closed to ensure there is no damage and no leakage.

IV. Three Requirements for Emergency Response

01 In the event of vehicle malfunctions, accidents, cargo spillage, or other emergencies, appropriate measures must be taken in accordance with the relevant emergency response plans and operating procedures, taking into account the specific hazardous properties of the cargo, such as explosiveness, flammability, corrosivity, extreme toxicity, or radioactivity.

02 If a vehicle is obstructing traffic and cannot be moved, the hazard warning lights must be activated as required. On ordinary roads, warning signs should be placed 50 to 100 meters behind the vehicle; on highways, they should be placed 150 meters behind. At night, the side marker lights and rear position lamps must also be turned on.

03 If initial response is not feasible, park the vehicle in an open area as far away from people and water sources as possible, and report the situation promptly. When reporting, provide detailed information on the name, physical form, quantity, and extent of the hazardous material leak to enable the relevant authorities to respond effectively at the earliest opportunity.

If a hazardous materials transport vehicle is involved in an accident

It even obstructed passage.

The occupants in the vehicle behind or the residents along the route

What precautions should be taken when rescuing oneself and escaping?

I. Prevent problems before they arise—pay close attention to these details in a timely manner.

01 Pay attention to following distance

First, be sure to identify vehicles transporting hazardous materials. At present, such vehicles are predominantly tank trucks, though some hazardous substances are also carried by conventional trucks. In accordance with relevant regulations, all hazardous‑material transport vehicles must display a “Dangerous Goods” label in a highly visible location. When driving on public roads, motorists should avoid traveling alongside these vehicles whenever possible; maintain a safe distance when overtaking or passing; and never deliberately change lanes or cut in front of them.

When traffic volume is high or vehicles are moving slowly, you may find yourself having to follow a hazardous‑materials transport truck for an extended period. Because tanker trucks have substantial mass and their overall inertia increases when loaded, it’s crucial to maintain a safe following distance. As a general rule, the vehicle behind should keep a sufficient gap from the hazardous‑materials truck; during heavy congestion, drivers typically leave one to two car lengths between themselves and the vehicle ahead—this space allows for adequate braking distance and helps prevent rear‑end collisions. Under no circumstances should you attempt to cut in front of such a vehicle and become its close‑following target.

02 Pay attention to the type of goods

If you must follow a hazardous‑materials transport vehicle for an extended period while driving, it is advisable—while ensuring safety—to note the specific type of hazardous material being carried. The name of the hazardous material is typically marked on the underside or side of the tank at the rear; this information will enable you to take prompt, targeted, and appropriate self‑rescue measures should the vehicle break down.

03 Pay attention to your surroundings

If a hazardous‑materials transport vehicle nearby is involved in an accident and its path is blocked, occupants of surrounding vehicles should evacuate the scene immediately. However, given the wide variety of hazardous materials and their differing hazard profiles, safe evacuation also depends critically on factors such as nearby water bodies, weather conditions, terrain, and wind direction. Therefore, while prioritizing driving safety, it is essential to remain alert to the surrounding environment and choose the correct escape route and direction when evacuating.

04 Key Points for Evacuation and Emergency Reporting in Hazardous Chemical Transportation Accidents

When evacuating, first leave the scene to avoid secondary accidents with other vehicles traveling normally; never drive in the opposite direction, cross the roadway, or walk on the highway. If you climb over the guardrail, be mindful of the roadside shoulder and ditches, as hazardous‑material liquids may accumulate there. When exiting bridge or tunnel sections, pay close attention to traffic flow and promptly move to an area with a slope or shoulder to exit the highway.

After evacuating to a safe area, vehicle occupants and residents along the route should immediately dial 119 to contact the fire department for assistance.

II. Strike First, Counter First: How to Escape in These Situations

01 Flammable and explosive—keep these items well away.

Common flammable and explosive materials include combustible gases, petrochemical products, explosives, and fireworks. Many flammable and explosive solids—such as ammonium nitrate, TNT, and white phosphorus—can detonate upon impact or friction; some may even explode upon contact with air or water. Moreover, their storage media, such as kerosene, are also combustible.

When transporting such materials, choose cooler times of day for travel, monitor the tank’s temperature and pressure, and avoid exposure to heat and direct sunlight. Drivers should exercise extreme caution when following such vehicles to prevent collisions. In the event of an accident involving these types of vehicles, immediately move away from the scene.

02 Gas and liquid leaks: Pay attention to the correct evacuation direction.

Gases and liquids can flow; in the event of a leak, choose an escape route based on their flammability, toxicity, water solubility, and other characteristics, taking environmental factors into account.

When there is wind, prioritize the upwind direction. In the event of a leak of toxic or flammable gases, or of liquids whose vapors are toxic or flammable, if wind is present at the scene, choose to evacuate upwind (against the wind). On slopes, select the vertical escape route carefully. If the incident occurs on a slope, in addition to considering wind direction, also determine the safest vertical escape path. Gases such as methane, carbon monoxide, ethylene, and acetylene are lighter than air; in still‑air conditions, seek to evacuate downhill whenever possible. Conversely, gases like benzene, chlorine, and phosgene are heavier than air; in still‑air conditions, aim to evacuate uphill. If the leaked substance is a liquid or a liquefied gas, evacuate to higher ground. Also, be aware that some liquefied gases are extremely cold; upon release, they vaporize and absorb heat, potentially causing severe frostbite on contact. Liquid ammonia and liquid benzene are additionally toxic, while leaks of liquid oxygen can increase the risk of explosion.

03 Changes upon contact with water—be especially cautious on wet roads.

Many hazardous chemicals undergo chemical or physical reactions when exposed to water, generating additional hazards. Therefore, during rainy weather or on wet road surfaces, seek higher ground whenever possible, and avoid contact with nearby bodies of water—especially puddles on the road or rainwater that has pooled at the accident site.

Ammonia, potassium cyanide, and sodium cyanide are all soluble in water and, upon contact with water, can produce toxic or corrosive liquids. Solid metallic sodium reacts with water to generate flammable hydrogen gas and a highly alkaline, corrosive solution; in the event of an accident, evacuate promptly and pay attention to the direction of escape. When concentrated sulfuric acid is spilled in large quantities, it releases substantial heat upon contact with water, causing the liquid to boil and splash, resulting in burns; therefore, during rainy weather, if a spill of concentrated sulfuric acid occurs, immediately move away from the site.

04 Corrosive acids—beware of inhaling vapors.

Nitric acid, sulfuric acid, and hydrochloric acid are well-known strong acids, and these corrosive substances should not be handled under any circumstances. Both hydrochloric acid and fuming concentrated sulfuric acid release corrosive vapors that can spread along low-lying areas; when evacuating, be sure to choose an escape route and protect your respiratory tract. In addition, nitric acid may ignite upon contact with certain organic materials (such as fibers), and it can react with metals—many highway guardrails are made of metal—to produce flammable hydrogen gas. During evacuation, pay close attention to your surroundings and take precautions against fire.

Source: Guangdong Emergency Management