Be certain that your children and family pets are not in the area where you plan to mow. It s best if you send them indoors to assure their safety. They may dart in front of the mower or be struck by and object the mower kicks out. It is not worth the risk. Always give your mower a thorough check before starting it.
Many older mowers have no safety devices.
New mowers are equipped with a rear skirt and a chute guard, which prevent objects from being thrown from the blades. Many also have a retaining post to hold the spark plug when the mower is not being used as well as a bail bar that stops the engine when it is released. Always be certain that safety shields and deflectors are in place. Never disconnect mower safety features. They may cause some inconvenience but they can save you a trip to the hospital.