HAZMAT CDL Practice Test

When hauling less than 100 pounds of Division 4.3 materials, which are materials that can react with water to emit flammable gases, the regulations permit the driver to not stop at railway crossings. This is because the quantity is considered sufficiently small that it does not pose a significant risk in this scenario, allowing for a more streamlined transit without the need for additional safety checks or stops. The decision to exempt smaller quantities of hazardous materials from stopping is based on the evaluation of risk associated with the weight involved. Therefore, for drivers transporting such limited amounts, continuing through railway crossings without stopping is permitted. This allowance helps facilitate the movement of materials while ensuring that the associated risks are managed appropriately.