When arriving at a scene, why is it important to block left and right?

Blocking left and right upon arriving at a scene is primarily important for protecting both the crew and the scene itself. By positioning emergency vehicles strategically, operators can create a safety barrier that shields personnel and victims from oncoming traffic, thereby reducing the risk of additional accidents. By blocking lanes, you also direct traffic away from the working area, ensuring that first responders can perform their duties without the danger of vehicles passing too close to the scene. This practice enhances the overall safety and effectiveness of the response by maintaining a controlled environment where emergency workers can focus on their tasks without distraction or risk of injury from traffic.