Not So Lethal Weapons

June 1, 1999

Not So Lethal Weapons

Common sense for power tool safety

By Michelle Garetson

June 1999


While I don't doubt Mel Gibson's prowess as an actor, I would be leery of casting him in a power tool safety video after watching the pneumatic nail gun scene in Lethal Weapon.

Though creative usage of power tools may be entertaining to see on the screen, it's no laughing matter when fingers or eyes are damaged or lives are lost on the shop floor as a result of dangerous practices. A thorough knowledge of equipment and shop safety procedures should be stressed to all employees. Whether the tools are battery-powered, electrical, or pneumatic; certain precautions and attitudes need to be taken before clicking on the switch.

Overall plan
Where to start? Manufacturers and distributors offer training for specific tools regarding unique safety features, but also have information for overall safety in the workplace. Many of their seminars include addressing the environments in which the tools will be used. Proper lighting and electrical outlets, work bench heights, and clean, dry floors all add to a safer environment for workers. (Please see sidebar on pg. 66 for more safety information sources).

Thou shalt not train in vain
Not every power tool requires extensive utility training before use, but tools such as air impact tools or those with unique ergonomic features should warrant some introductory tuition. All equipment includes, or should include, instructions and safety suggestions from the manufacturer. Those people wishing to just hit the highlights of the instructions and figure out the rest later are not doing themselves any favors — the "trial and error" method is no way to learn the capabilities of a power tool! A few minutes taken to review safety procedures could mean the difference between keeping your livelihood and keeping your life.

"Most often, safety training is conducted in-house by the company that bought the equipment," says Joe Spry, marketing manager for Sears Industrial Sales in Hoffman Estates, Illinois. "Our account managers can arrange for the source (equipment manufacturer) to come into the facility to offer training, and most of the time, this training is done for air impact tools. It's important to stress understanding the tool's use and especially its limitations. You don't want or need a high impact wrench for tightening something that a nut runner would be better suited for."

Andy Mandell, assistant marketing manager for Dynabrade Inc. in Clarence, New York, adds that their salespeople and/or tech services personnel offer safety presentations to distributors as well as to the end user.

"Safety is definitely stressed during these seminars," says Mandell. "First, the safety features of the particular tool are discussed, then the safety of the environment in which the tool will be used."

While it is everyone's responsibility to understand safety procedures in the shop, it is crucial that management charge themselves to continually stress safety in the workplace and keep employees in tune through proper and timely training.

Preparing the work place—physically and mentally
Minimizing distractions in the work area goes a long way toward safeguarding employees. While management can take care of removing the physical obstructions and the posting of proper signage in the work area, employees need to realize their own responsibilities and limitations. Recommended or mandated personal protection gear such as face shields, eye, ear, hand, and foot protection should be worn; whereas, loose clothing, jewelry, and watches should not be worn when using power tools. AMT has some eagle eye readers who have caught us in the past featuring photos with technicians wearing rings or watches, or not wearing proper safety gear for the job. We thank you for your attentiveness and ask that you keep up the good work for the safety of your peers.

Also, any type of ladders, portable manlifts, or scaffolding should be of correct height and stability for the job. Overreach is a major cause of portable power tool accidents — save the "one foot on the floor" rule for shooting pool.

Concentrate on the task at hand and do not let yourself become distracted by a co-worker. Never operate power tools when tired, ill, or under the influence of drugs or alcohol. All of your faculties must be in place at the start of the task to ensure they'll be there when the job is done.

Altered states
Another tip that may save you an extended lunch hour in ER is to not remove any safety guards from equipment.

"Tools should not be manipulated to detract from its intended use, though we know it's done," warns Mandell. "Modification or alteration of any kind to a power tool should be left to the design engineers at the manufacturer."

Plain and simple — safety guards guard your safety.

Batteries included
Cordless tools are great for getting at work in tight areas or where electric- or air-powered tools are not feasible.

"The beauty of these is that they are transportable, often more so than electrical or compressed air tools," explains Brad Mountz, president of Mountz Inc. in San Jose, California. "Also, air hoses are cumbersome to drag through the cabin of a plane, and many times, customers don't want things like that dragged through the plane."

However, battery-powered tools have the potential for inadvertent operation because they are always supplied with power with the battery installed. To prevent surprise startups, check that the switch is in a locked-out position, or, if possible, remove the battery pack. Battery packs should also be stored away from conducting objects that could bridge and short-circuit battery terminals, which could lead to a fire.

Shock therapy
The Occupational Safety and Health Administration (OSHA) offers specific rules for using electrically powered tools. These guidelines and the use of good judgment will help avoid most, if not all, common mishaps. Before using the tool, check that it has an electrical test label stating that it successfully passed inspection and tests for safety. According to Joe Spry, all of Sears' electrical products are UL (United Laboratories) listed to maintain consistency and safety. As he stressed before, know the application and limitation of the tool and operate according to the manufacturer's instructions.

Cord inspection is important. Electric-powered tools must either have a three-wire cord with ground or be double insulated. Removing a ground prong from a plug because the nearest outlet only has two slots is a definite no-no. Frayed cords should also be avoided as should be loose or broken switches. All of these sorts of items should be removed from service and labeled "Do Not Use" until they can be repaired.

Another safe practice that bears repeating when using electrically powered tools is to avoid damp or wet areas when using these tools. If this is not possible, wear gloves and footwear designed for those conditions.

However, Mountz points out that electrical tools are gaining ground in popularity. "Some can be interfaced with computer applications. Plus, the power source is cheap."

Misuse of pneumatic power
Pneumatic equipment produces a mechanical force by using confined, pressurized gases. Very powerful, but also hazardous, as evident from Gibson's nail gun scene, if those forces and gases are not harnessed correctly.

"Air lines on compressors should be checked before each use," reminds Mandell, "for water, oil, etc. that could disrupt air flow."

Operators should have a thorough knowledge of how the equipment works and its specific applications. Though Tim "The Tool Man" Taylor might find pneumatic power handy for cleaning the shop floor quickly, this practice should never be attempted. Miniscule meteorites of shop debris could cause bodily injury to you or a co-worker, as well as become lodged into the tight spaces between moving parts of machinery, which could cause parts to lock up and damage equipment.

Calibrating power
"A drill doesn't have to be calibrated, but any tool that is a measuring tool or has measuring capabilities should be calibrated," says Mountz. "Torque wrenches, hand or pneumatic, should be calibrated."

While he recommends a bi-annual or 6-month cycle, he also suggests halving the cycle if the equipment is found to be out of calibration at the 6-month check.

Dan Grippo, product manager for Atlas Copco Tools in Farmington Hills, Michigan, offers that threaded fastener-type tools and those tools that need to achieve torque should be calibrated according to application and use.

"We suggest calibration for tools after a set amount of cycles, say every 250 cycles," offers Grippo, "as opposed to a specific time constraint as in a 3- or 6-month schedule."

Getting a handle on it
Ergonomics, an applied science that melds characteristics of the product with those of humans for safety and efficiency, has become an important issue in the workplace.

OSHA has recently drafted a proposal for a national ergonomics program. Estimates from OSHA suggest that more than 647,000 Americans suffer from work-related musculoskeletal disorders, or WMSDs, due to ergonomically poor working environments, which account for more than 34 percent of all work-related injuries and cost between $15 to $20 billion annually. The jury is still out as to whether or not this proposal will pass as is, but businesses, large and small, should be aware that it exists.

"Atlas Copco developed the pistol grip handle about 40 years ago," says Grippo. "Medical doctors were consulted and worked with our ergonomists to develop proper design for customers."

Grippo adds, "Things considered in ergonomics are to reduce the forces on the operator. Vibration forces, reaction forces, and things like the weight and balance of the tool are studied."

Differences in use — repair vs. manufacturer — need to be considered as well. Repetitive use for long periods of time with a vibration-heavy tool, as in a manufacturing scenario, can lead to a condition commonly known as "white finger" disease. White finger, a.k.a. Traumatic Vasoplastic Disease, is caused by the combination of vibration and cold, as in excessive use of pneumatic tools. The symptoms included a deadening of the fingertips or fingers from a block in blood circulation, which can cause digits to become pale or white, and feel cold.

Clicking off the switch
While this may have sounded like a quick lecture in doom and gloom, or a paid advertisement for emergency rooms everywhere, it is hoped that the information presented be a reminder to use common sense. Leave the theatrics to Mel on the movie set — he's a professional at what he does — just as maintenance personnel are professional in what they do, everyday, in every way, when performing in their jobs.