A flare is a pyrotechnic device which creates a bright light or intense heat without causing an explosion. The ingredients used in flares vary, but are often based on strontium nitrate, potassium nitrate, potassium perchlorate, and mixed with a fuel such as charcoal, sulfur, sawdust, aluminum, magnesium, or a suitable polymeric resin. Some flares are even able to burn underwater through the use of calcium. Typically red in color, flares can be used for long burning periods, such as 10 – 60 minute road flares, or for shorter burning periods such as with signal flares shot from a flare gun.
During the Tyrannosaurus‘ attack on the main road of Jurassic Park, Alan Grant and Ian Malcolm used road flares that were activated via a pull tab on top of the flare. The bright lights of the flares successfully distracted the dinosaur, first drawing it away from the car containing Tim and Lex Murphy by Grant, and then away from both vehicles by Malcolm, though this resulted in Malcolm’s injury and the death of Donald Gennaro. Eight years later on Isla Sorna, Grant used a flare gun to distract the Spinosaurus as it attacked him and the Kirbys. The flare bounced off the dinosaur’s hide, but ignited fuel which had leaked into the river when the spinosaur attacked the boat, driving it away and into the jungle.