Starting in late May, linemen in parts of the Eastern and Midwestern United States will have to contend with an unusual problem: cicadas. Emerging from the ground after 17 years, millions of these large insects make a sound like an alien horror movie. They will climb into trees in massive numbers and rub their wings together to create a tsunami of sound designed to attract mates. Reaching 90-100 decibels, cicadas are louder than a jackhammer, complicating communication between utility workers, who need to work near the lovesick insects.
For any endeavor, clear and reliable communication among team members is essential. That’s especially true of utility workers, where a lack of communication can lead to delays in power restoration, skipped maintenance and severe worker injuries. Noise from the cicadas brings an added challenge to a worksite where it’s already hard for workers to talk to each other.
Crews may need to use hearing protection just as they do for chain saws, which makes it hard to hear their two-way radios. The radios are essential for talking to physically distant team members who may be on the ground, up in a bucket, or a half mile down the road. Some workers may be tempted to remove their hearing protection, if only temporarily, in order to hear their radios over ambient noise.
Fortunately, new technology can help. Wireless communication headsets, such as those made by Sena Industrial are available with built-in ear-muff style hearing protection. Noise reduction ratings for headsets mounted on hard hats are 20 to 24 decibels. These devices allow workers to talk to each other while working safely.
The headsets have a number of differences compared to radios, whose technology dates back to the 1970s. Radios use a low-frequency FM band, while the headsets use the high-frequency Bluetooth band around 2.4 GHz. The lower frequency gives radios a long range and makes them good at communicating around obstacles.
The downside is that radio technology is analog. Instead of the characteristically muffled sound of radios, wireless headsets have high-definition digital sound and noise cancelling. Clear sound can reduce misunderstandings and avoid having to repeat instructions.
In addition, radio technology is half-duplex, allowing only one person to speak at a time, after pressing a button. The listener must wait to reply. Sometimes this means a worker gets only half of a message. In contrast, Bluetooth headsets are full duplex, letting multiple people talk and listen at the same time, speeding conversations. There is no need to push a button, so hands can stay on task. Hands-free operation improves worker productivity, and it improves safety by allowing one worker to warn another of a hazard immediately.
Two different types of headsets are available, defined by which long-range Bluetooth profile they use: Bluetooth Intercom or Mesh Intercom.
Bluetooth Intercom Headsets
While consumers are familiar with near-field Bluetooth used for phones and earbuds, the Bluetooth Intercom profile used for industrial purposes is long-range and robust, covering 0.5 to 0.8 miles in the open air.
Setting up a Bluetooth Intercom network is simple: just pair one wireless headset to another, usually limited to four total devices. In contrast to radios that use a popular public band, Bluetooth devices offer a level of privacy and security because of the pairing. Workers will not hear chatter from people outside of their team and vice versa.
Mesh Intercom Headsets
Wireless Mesh headsets, such as those using Sena's proprietary Mesh Intercom protocol are similar to Bluetooth headsets except that the Mesh topology uses headsets to relay the signal to other nodes in the network. The network continuously polls devices and selects the most efficient signal path.
A Mesh system offers more coverage than a Bluetooth Intercom system. For example, the range between two Sena Mesh devices is 0.7 miles in open air, but as devices relay the signal, the coverage area is expanded to cover a much larger area. The other advantage of a Mesh system is the ability to connect an almost limitless number of devices. This is helpful for large work teams doing vegetation management, installation, and construction.
Mesh networks are self-healing: when a team member leaves the coverage area, the headset automatically reconnects to the network upon their return. No pairing is required.
Prepare Crews for the Invasion
Cicada broods are staggered, so that different regions experience them in different years. This means that many outdoor workers will encounter them at some point in their careers. Managers can prepare their crews by outfitting them with noise-reducing wireless headsets. Whether noise is caused by cicadas, or more typical sources such as saws, weather, and vehicles, workers can use wireless headsets to communicate easily and safely.
