1988 was a big year for wildfires in the western United States, with more than 72,000 fires reported during the year, including 300 rated as major. Firefighting employees and equipment were stretched to the limit, and consequently, more than 6,000 U.S. Military personnel assisted in the fire fighting efforts nationwide, with more than 600 assigned to Yellowstone. At the height of the fires, more than 9,000 firefighters and support personnel were assigned to Yellowstone at one time, and by the time the fires finally went out, more than 25,000 had been involved in the fire suppression efforts. Crews would normally work for two to three weeks, be sent home, and then return for one or two more tours of duty. The normal workday was as long as 14 hours. Assignments included digging firelines, watering down buildings, clearing undergrowth near structures, and installing water pumps. Hundreds of firefighters were assigned to engine crews, as much of the firefighting effort was aimed at protecting structures. No firefighters died in the park as a result of the fires, but one firefighter and an aircraft pilot died in separate incidents outside the park. A number of firefighters were treated for various injuries with the more common complaints being fatigue, headaches, and smoke inhalation. A few firefighters were exposed to noxious fumes from sulfur emissions from a geothermal area.