Lawn equipment accidents happen quickly and can be extremely dangerous, especially when they involve a string trimmer. The furious action of the turning head and plastic string can cause injury in of itself not to mention the flying dust and debris, creating a dangerous situation for both the operator and bystanders. From the noise of the engine to the potential for flying objects, string trimmers are among the most dangerous of the lawn care tools.
Personal Protective Equipment
Always wear the appropriate personal protective equipment (PPE) as recommended by the manufacturer. This most likely includes gloves, long pants, long sleeves, ear protection, eye protection, and even face protection. Anyone who has operated a string trimmer knows the personal assault inflicted when the trimmer gets too close to some sand or gravel. Sand and debris can pose an injury not only to the operator but bystanders as well, so caution must be taken as to when and where the trimming is taking place.
Extended, repeated exposure to the engine noise of a string trimmer can cause ear damage, and hearing protection is always recommended either earmuffs or earplugs. Eyes and face should be protected with a full face shield, and adequate clothing should cover up the rest of the areas you don't want to get sandblasted, or pelted with rocks.
Similarly, an employer should always provide the appropriate PPE to workers who are using string trimmers. An employee should be expected to wear long pants and sleeves, but ear, eye, and face protection should be made available by the employer.
Operator awareness is essential when using string trimmers. Look out for people and pets, especially children who may be attracted to the machine. Always stop using the trimmer if people are around or until they have passed. The potential for stirring up flying rocks puts windows in jeopardy in houses and cars alike. Shields around the trimmer head are in place to reduce the amount of flying debris and protect the operator -never remove the shields, once modified a trimmer is no longer under warranty or usable in a safe manner.
When refueling, be sure engine is stopped and trimmer is placed on a flat, even surface - preferable not grass. The trimmer should never be left sitting on the grass for extended periods. Re-fueling should be done with the appropriate portable fuel storage system being careful to avoid spillage or over-filling.
Be sure to use the appropriate string weight as specified in the owners manual. Trimmer string that is too thick for the engine could cause damage. Some trimmers can accept an edging blade, however, never use a blade on a trimmer that was not designed to use edging blades. Accessories that are not meant for a specific trimmer can create excessive vibration, engine wear, or bogging down. This could result in engine stress, eventual component failure and potential harm to the operator.
Safe storage and transport
String trimmers should be rinsed clean of any debris and grass clippings after each use. The trimmer head should be clear of long grass or other long items like string or plastic which may have wrapped itself around the shaft. String trimmers can be stored horizontally or vertically so long as they are not turned on their side causing the fuel to rest against the cap and potentially leak. When storing a string trimmer for more than a couple of weeks or the winter, use proper winter storage techniques.
When transporting a string trimmer be aware of the shaft and how it may move around while in transport. Trimmer shafts often become bent because of improper storage while traveling. The shaft could be bent while bouncing around in the back of a truck or by coming in contact with an immovable object. String trimmers need to be properly secured to limit movement while in transport.
The damage a string trimmer can inflict is severe whether from flying rocks and debris or the string of the trimmer head itself. Extreme care must be taken in both personal safety and the safety of others including the potential to damage property like windows. String trimmer operators can only benefit from practicing common sense safety.