The Key to Lawn Mower Safety is You!

Posted: May 7, 2013

Even though we are well into the lawn mowing season it is worthwhile to review the hazards associated lawn mowers and their safe operation. Each year thousands of injuries are caused by power lawn mowers. Many of these accidents involve children under the age of five years old, and usually result in grotesque injury and/or the loss of fingers, toes, limbs, or eyes.

The whirling metal piece below the mower deck is an inexpensive and effective method of shearing a variety of vegetation. However, approximately 70 percent of all lawn mower accidents are caused by blade contact. A person can come in contact with the blade by slipping under the mower deck, or reaching into the discharge chute. Lawn mower blades typically turn at 3,000 to 3,600 revolutions per minute, or 50 to 60 revolutions per second. Since the blade has two cutting edges, an object in line with the blade for only one second can be struck as many as 120 times. The intensity of the damage from a blade rotating under these conditions is roughly equivalent to a 1.2 pound missile traveling at 232 miles per hour. Bones coming in contact with the mower blade are typically crushed and the wound filled with dirt and grass, making it difficult for a surgeon to repair.

Another major cause of lawn mower accidents are objects thrown from the mower. Stones, sticks, and other debris can be launched from the discharge chute with enough force to puncture the skin, or eyes, and cause serious injury.

Over the past few decades, manufacturers have – by choice or mandate – made design changes, such as improved guarding and "dead-man brakes", to reduce the danger of lawn mowers. Dead-man brakes are designed to stop blade rotation in three seconds or less if the operator lets go of the push handle, or gets off the seat of a riding mower. However, some operators see these devices as a nuisance and by-pass them using wire or tape. Guards and deflectors are in place to reduce the chance of burns from hot surfaces and direct foreign objects, such as sticks and stones, thrown from the discharge chute to the ground. Guards and deflectors should never be removed to allow better maneuverability. These safety devices can greatly reduce the hazards associated with power mowers and must be left in place and operable to be effective. A temporary inconvenience can prevent permanent injury.

Many hazards can be reduced by the operator. The most effective way to avoid injury is to recognize the hazards present, and learn how to operate the machine properly. The owner's manual and your local dealer are good sources of information for operation and maintenance. 

Before starting to mow the lawn, the operator should:

                   • understand the proper use and operation of the mower
                   • clear the area of sticks, stones, and other debris
                   • clear the area of children, adults, and animals
                   • wear sturdy footwear such as work shoes or steel toed boots
                                                (never sandals, sneakers, or bare feet)
                   • wear close fitting slacks and shirts to avoid entanglement
                   • make sure all guards, deflectors, and safety devices are in place
                     and working
                   • check fuel before starting (do not add fuel when engine is hot!)

While mowing the operator should:

                   • wear eye and hearing protection
                   • pay careful attention to the operation of the mower
                   • move slowly over rough terrain
                   • direct the discharge chute away from cars, buildings, and people
                   • look ahead of the mowing path for debris
                   • look before backing
                   • not operate a mower on a grade steeper than 15 degrees
                                               (2.5 ft. rise per 10 ft run)
                   • operate RIDING mowers UP & DOWN slopes
                   • operate WALK BEHIND mowers ACROSS slopes
                   • never attempt to adjust cutting height while mower is running
                   • never operate on wet grass
                   • never pull a mower up a grade while running
                                                (you might slip under the mower)

When purchasing a new or used lawn mower keep safety in mind. Select a machine which reduces the hazards present in making your lawn look nice. But more importantly, be aware of the danger of your lawn mower, respect the hazards, and take action to avoid accidents with proper, careful use. The key to lawn mower safety is you.

Dan McFarland is the Extension Agricultural Engineering Educator serving Adams County. Dan is based in the York County Extension Office and can be reached by phone at 717-840-7408 or e-mail Penn State is committed to affirmative action, equal opportunity, and the diversity of its workforce.  Penn State Extension in Adams County is located at 670 Old Harrisburg Road, Suite 204, Gettysburg, PA  17325-3404, phone 334-6271 or 1-888-472-0261,
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