Most injuries result when a farm worker gets to close or comes in contact with PTO drivelines. It consists of a telescoping shaft, meaning that one part of the shaft will slide into a second. Figure 1 is a diagram that shows the important parts of a PTO driveline. The PTO and PTO driveline are very important and useful production agriculture tools, however if left unguarded, improperly hitched, and taken for granted, they can become extremely lethal devices. At these speeds, clothing, hair, and limbs are pulled around the PTO driveline much quicker than a person is able to pull back to take evasive action.
Reaction time varies by individual, age, and physical condition.
These speeds are normally reached when the tractor has been stopped but not turned off, and the PTO is left engaged. They are very important engineering controls for reducing hazards in production agriculture. PTOs and PTO drivelines are required and should be shielded. Unfortunately, many tractors in use today, especially those older than 1976, are not properly guarded. There are many reasons that shields or guards may be missing from the PTO and PTO driveline.