An average of 132 American farmers were crushed to death annually when a tractor overturned during operation. Nearly all these fatalities were preventable, according to a NIOSH report, by installation of a rollover protection structure (ROPS) on each tractor in use. A ROPS is like a roll bar that protects the operator during an overturn. Seat belts should be used in conjunction with the ROPS to protect the operator. The ROPS became available as optional equipment to be added to a tractor in 1971. A study in Nebraska found that 40% of 250 persons involved in unprotected tractor rollovers died, compared with 2% of persons operating a tractor with ROPS that overturned. National and community injury prevention programs should retrofit or refurbish older equipment without ROPS to prevent deaths during rollovers.