Traffic congestion caused by incidents affects the safety and mobility of all travelers. Major incidents can affect thousands of vehicles in an entire highway corridor or network. Additionally, this congestion can cause secondary incidents that also require response from the same agencies already engaged in the primary incident. Secondary incidents are not just crashes but also include engine stalls, overheating, and running out of fuel. Approximately 20 percent of all incidents are secondary incidents.
Traffic incidents are primarily public safety events. Public safety agencies, such as law enforcement, fire and rescue, emergency medical services (EMS), and other emergency management agencies are first to respond to traffic incidents. Transportation agencies usually play a secondary, but vital, support role. Private sector entities are also involved, most commonly from the towing and recovery industry. Efficient and collaborative incident management strategies help keep the public, as well as responders, safe and moving.
Adapted from the Federal Highway Administration's Traffic Incident Management page.