The Ergonomics of Power Tools
Managers specifying power tools might not mention ergonomics specifically when discussing their top priorities. But rest assured that the issue is moving closer to front and center all the time.
This evolution is occurring for a number of reasons. First, tool users are paying more attention to how tools feels in their hands and how they feel once they have finished using them. Second, tool manufacturers — having for the most part maximized power, run times and durability — increasingly use advances in comfort and ergonomics to distinguish themselves from their competitors.
“Ergonomics is one factor that manufacturers are going to use to differentiate their tools,” says Jay Gatz, director of brand and channel marketing for Ridge Tool Co.
Identifying the changes that tool specifiers and users want when seeking tools that are more comfortable to use has proven difficult, manufacturers say. Users often pay closer attention to horsepower and run time and in some cases are not even aware of a problem.
“The ergonomics issue isn’t often articulated by users because they have developed work-arounds,” says Tom Smith, group product manager for Milwaukee Electric Tool. So instead of using the uncomfortable handle of a tool, a worker is more apt to grip it by the motor housing, which is more comfortable, even though designers never intended it to be used that way.
“Ten years ago, you could get away with less differentiation,” says Mike Hibbison, director of marketing for Porter-Cable. “Today, ergonomics is probably more important than ever.”
Once manufacturers have a chance to talk with power tool users and specifiers, however, they get insights into changes that will make tools more comfortable to use, and in turn, protect workers’ health and safety.
“These changes not only make it more likely that a user will pick up a tool and use it properly, but they also can reduce health care costs,” Smith says.
Changes in power tools to improve ergonomics often address their weight, balance, shape and vibration, as well as the less definable issue of comfort.
Manufacturers have developed lighter-weight tools by using in part by using lighter materials for housings. Polymides with fiberglass reinforcements are becoming more common because they are extremely durable and lighter than metal, says Dennis Hoops of Hilti Tools. Tool specifiers also are likely to see more magnesium tool housings because of its durability and lighter weight. Still, gains from changes in housing materials might have peaked.
“You can only get so much blood from a turnip,” says Randall Coe, director of product development for Bosch Power Tools.
Instead, more manufacturers are using advances in electronics to make tools lighter. Newer tools might feature electronic clutches, which use less space and are made of lighter-weight materials than their mechanical predecessors, Coe says.
Smith adds that advances in fan design also allow manufacturers to increase tool horsepower without adding weight from a larger motor or more copper windings — an advance no doubt tops the priority list for all users.
Striking a Balance
Balance often is a more subjective issue.
“Sometimes, a heavier tool may actually feel lighter because it’s better balanced,” says Todd Walter of DeWalt Tools. “It’s easier for the user to hold, and it feels more natural. Cordless tools are designed with battery placement in mind because the location of the battery can affect balance.”
A tool’s balance also relates to how a particular user’s hand feels when holding it.
“There is more contouring toward the hand so that the tool is more of an extension of the hand, rather than just something you pick up and use,” Smith says.
Related to balance is location of switches, grips and other features users must have easy and comfortable access to when operating a tool.
“If a tool is meant to be used continuously, the switch design and position also fits into the ergonomics picture,” Walter says. “The switch may be a rocker style or a slide style and would be positioned in close proximity so the user can access it conveniently without losing control of the tool.”
The performance issue that causes the most problems for many users is vibration, especially when using larger tools for long periods of time.
“Generally, heavier tools that produce more vibration and more power, such as rotary hammers, large drills, demolition hammers, and large grinders, will have designs that dampen vibration and improve hand position or grip,” Walter says.
So a reciprocating saw might incorporate a counterbalance mechanism to cut vibration, or a hammer drill might use a vibration isolation device to achieve the same goal, Smith says. Most manufacturers also have come out with tools that have a foam or gel grip to address concerns over vibration.
“Everyone’s put rubber in their grips, and that’s been one of the most impactful change,” Hibbison says.
On the Horizon
Manufacturers and tool specifiers alike have only recently begun to pay serious attention to ergonomics. So it seems likely that, which advances in power, durability and battery life have slowed, specifiers are likely to see a significant number of advances related to ergonomics.
From focus groups and field tests to consultations with university professors over the contours of tool users’ hands, manufacturers are investing in diverse areas of research in an effort to make tools more comfortable and easier to use.
“Manufacturers are trying to be more cognizant of ergonomics in an effort to get tools to be smaller and easier to use,” Smith says. They all agree that the next generation of power tools will be still smaller, lighter weight, more comfortable to use and more attuned to the particular needs of specific maintenance tasks than current power tools — all without sacrificing any of the performance, power and durability that users have come to depend on and that are essential for daily maintenance.