Ergonomics Increases Productivity, Safety
BY Tim Hoffman
The most productive tools are those that are accurate, easy to use and get the job done quickly. When it comes to road construction projects that time is vital. That’s why hundreds of asphalt rollers and soil compactors are packed with features that turn compaction science into a cinch, such as active bouncing control, intelligent compaction technology and ergonomic operating stations.
While ergonomics might sound like a fluff word used to describe a comfortable chair or steering wheel, it can have a big impact on the overall job. Ergonomic designs create ideal working conditions and make construction equipment easy to operate, which sets the stage for increased productivity. This is why it’s important to look for ergonomic and timesaving features when purchasing or renting equipment.
Ergonomics is an applied science that considers devices, systems and physical working conditions, and how each relates to the capacities and requirements of the worker. In other words, it’s how the operator’s body relates to the machine. When it comes to construction equipment, asphalt and soil rollers are great examples of how ergonomics can have a huge impact on the operator and the project.
These operators are on the machines for 8 to 12 hours per day. If the roller isn’t designed to allow operators to work comfortably without straining or bending, it could impact the project schedule and will eventually take a toll on the operator’s body.
Ergonomic designs reduce the time that operators spend in fatigue-generating positions, such as leaning to get a good view of drums. To do that, manufacturers must consider how operators maneuver their bodies to adapt to changing work conditions. Successful solutions create a safe environment and keep the operator comfortable. And a comfortable operator is a productive operator.
There are many features you can find on rollers that contribute to ergonomics, including rotating seats, built-in controls, vibration switches, sound dampening engines and heat gauges. And they all add up to greater efficiency.
An operator needs to have superior visibility of the equipment and worksite, not only for safety reasons but also for productivity. If the operator doesn’t have a clear view of the drum edge he must rely on his best guess or someone else for guidance. This not only increases the risk of damaging curbs or other obstacles, but also consumes time. One way to ensure clear sightlines to the drum edge is a moveable seat, rather than a stationary seat. A moveable seat can adjust with the operator, which increases visibility without making him or her lean or twist the body. Some rollers even feature 180-degree spinning seats to make looking to the front and back of the machine easier. Sideways sliding seats also allow the operator to comfortably move from one side of the roller to the other to maintain optimal visibility and avoid having to strain his or her neck to get a clear view of the drum edge. It also gives operators the confidence to work faster.
Having a clear view around the machine is just as crucial for the safety of nearby workers.
Along with seat positioning, ergonomics also pertains to the controls. In fact, the industry has mandated requirements on ergonomics and the placement of switches and buttons. Designs are based strictly on helping the operator focus on the rolling process rather than looking down at the console. When controls are in the optimal position, operators can quickly and comfortably move from one switch or button to the next, making the process more fluid. It doesn’t seem like much, but over time it can help increase production.
Controls also should be grouped based on function for optimal operator efficiency and familiarity across multiple pieces of equipment. Manufacturers that make several pieces of equipment that are similar to one another – such as soil rollers and asphalt rollers – usually position controls consistently across all the machines. This saves operators time from familiarizing themselves with the controls. Not only should controls be easy to use and identify, but also categorized together for even greater efficiency, such as propel functions, vibratory functions, water controls and auxiliary functions.
To provide maximum equipment control for operators, some manufacturers attach controls directly on the right side of the operator seat. This provides uninterrupted access to controls, even when the operator is rotating the seat for better visibility.
Knowing how the roller is operating is critical to superior compaction and avoiding unexpected downtime. A roller’s display should clearly indicate vital operating parameters, such as ground speed, vibration frequency, fuel level and coolant temperature. It also should alert operators to malfunctions or improper usage as well as diagnostic codes and service intervals.
Finally, all controls, symbols, warnings, gauges and instrument panels should be easy to read. The standard use of ISO symbols or registered universal symbols on panels and controls helps any operator react to changing conditions despite possible language barriers.
The whole basis of how asphalt and soil rollers work not only comes from their weight and size, but most importantly their vibrations. While this makes the compaction process more efficient it can have the opposite effect on operators. Over time vibrations generally make it uncomfortable for operators to grip the roller’s controls, which can impact productivity. Look for models that allow operators to toggle drum vibrations on or off when they’re not needed. Some manufacturers reduce vibrations by incorporating extra insulation throughout the roller. Keep in mind that rubber compound materials will significantly absorb and reduce vibrational impact on the operator. That’s why some manufacturers place a series of rubber shock mounts between the drum and frame, as well as underneath the platform or cab. And on some 25-ton static rollers, operator cabins sit on compressed airbags – sometimes called floating cabins – which do wonders to minimize vibrations and boost operator comfort.
A Sound Choice
Loud diesel engines and handheld tools make communicating with crew members a challenge on construction sites. When an operator can’t communicate with other crew members and visa versa, they could be missing out on vital information that can impact jobsite efficiency and safety. To help minimize noise and promote easy communication, look for rollers with cabs that reduce outside noise to less than 80 decibels, which is as quiet as a dishwasher. They allow the operator to easily communicate with crews using a walkie-talkie or hand signals. And minimal engine noise lessens the risk of hearing damage for the operator.
Diesel engines and handheld tools aren’t the only source of noise – large hydraulic pumps used for a roller’s drive or vibration functions also can contribute. Some manufacturers minimize noise by optimizing the vibration characteristics of hydraulic pumps with respect to the engine. This design allows manufacturers to continue using powerful engines while significantly reducing the noise.
Going the Extra Mile
Other timesaving features can make all the difference for the roller operator. For example, when compacting asphalt, it’s common to have a second person with a heat gun periodically checking the asphalt temperature. But a heat gauge incorporated right into the roller can do the job while saving time and labor costs of a second person. And it is less fatiguing because it eliminates the need to mount and dismount the roller if the operator is doing the checks herself.
It’s in the Details
Dissecting asphalt and soil rollers provides solid examples of what to look for in terms of ergonomics on a machine. Each piece of equipment comes with a whole new world of features to select, because not all machines are created equal. While some of them seem minor and tedious, consider the advancements in productivity and safety they create. Suddenly a few simple features, or a higher quality machine, seem like something that should be a priority.
Tim Hoffman is the product manager for Atlas Copco Road Construction Equipment’s heavy compaction line.