A tourniquet is generally reserved for severe, life-threatening bleeding from an arm or leg that cannot be controlled by direct pressure alone. Common signs of life-threatening bleeding include blood that is spurting, pooling, or rapidly soaking through bandages.
To gain the skills needed to use a tourniquet safely and effectively, consider taking a "Stop the Bleed" or first aid course. Organizations like the American Red Cross and the American College of Surgeons offer training programs that teach bystanders how to become immediate responders in a bleeding emergency. Tourniquet
Being prepared with both the right equipment and the right training can make a significant difference in an emergency situation. Bleeding Control First Aid: Save Lives with Tourniquets Tourniquet