At 33,424 acres, the Apple fire was 95 percent contained Monday, August 17, as remaining crews worked in the heat to put out hot spots and keep the fire in the containment lines. Fewer than 250 personnel were at the scene, working in steep terrain as they work on repairs to the land in the burn area, the fire command said. Containment is when firefighters create and hold a fire break around the perimeter of a wildfire. Crews including the Big Bear Hotshots made progress on the northeast corner of the fire, and all personnel worked under an excessive heat warning expected to last into Thursday night. Four injuries, all minor, to firefighters, have been reported. Personnel will be reassigned as needed for other fires burning throughout California. The Apple fire started just before 5 p.m. July 31 in Riverside County’s Cherry Valley, ignited by a diesel vehicle with a faulty exhaust system that spewed hot debris into brush alongside Oak Glen Road, investigators said.