A power take-off (PTO) is a drive shaft that transfers mechanical power from a tractor to an implement, such as a brush hog, bailer, or chopper. Every piece of equipment that has a PTO comes from the factory with a safety shield covering the rotating shaft to keep body parts from catching in them.

State Fund loss prevention consultants report it is common to see PTO shields missing on farm equipment. Overlooking a hazard such as this is an accident waiting to happen.

How fast are PTOs?

  • PTOs usually rotate at either 540 RPM or 1,000 RPM.
  • A PTO at 540 RPM pulls in seven feet per second.
  • A PTO at 1000 RPM pulls in thirteen feet per second.
  • The average person’s reaction time is about three quarters of a second.
  • At 540 RPM, the average person would be pulled into the PTO about 5 ¼ feet before they even realized that they were in danger.

With this type of hazard, it is easy to see why manufacturers include PTO guards. These shields cover the shaft, but do not rotate with the shaft; keeping clothing, arms, and legs from being caught.

Facts about PTO guards

Guarding a PTO system includes a master shield to guard the tractor PTO stub and connection end of the implement input driveline (IID) shaft. The PTO master shield attaches to the tractor and extends over and around the PTO stub on three sides. Both a driveline shield and a master shield are needed for maximum protection.

Master shields are removed or are missing from tractors for several reasons including:

  • Damaged shields that are never replaced.
  • Convenience of attaching machine drive shafts.
  • Used tractors being sold or traded and never replaced.

Not having a master shield and/or a driveline shield is a citable offense by Cal/OSHA and is very costly to replace. Although it takes time to replace, preventing devastating accidents is worth the time and money.