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Fighting fatigue: using technology to reduce risk of fatigue-related incidents on the jobsite

The Driver Safety System (DSS) monitors driver fatigue.
The Driver Safety System (DSS) monitors driver fatigue.

When a person is fatigued, the operation of heavy machinery or hand tools can become very dangerous. “A fatigue-related incident is more severe than a non-fatigue related incident,” said Todd Dawson, Project Manager for Cat Safety Services, at a recent Caterpillar trade press event. “People that fall asleep when they’re operating equipment or vehicles, they don’t do anything. They just run into whatever’s in front of them or run off the edge at whatever speed they’re going. A drunk driver, they’ll swerve. They just swerve too late or they put on the brakes. They just don’t put them on quick enough.”

According to the Canadian Centre for Occupational Health and Safety (CCOHS), WorkSafeBC reports that:

  • 17 hours awake is equivalent to a blood alcohol content of 0.05
  • 21 hours awake is equivalent to a blood alcohol content of 0.08 (legal limit in Canada)
  • 24-25 hours awake is equivalent to a blood alcohol content of .10

So, what is fatigue and what causes it? According to the CCOHS, “Fatigue is the state of feeling very tired, weary or sleepy resulting from insufficient sleep, prolonged mental or physical work, or extended periods of stress or anxiety. Boring or repetitive tasks can intensify feelings of fatigue.”

Acute fatigue results from short-term sleep loss or short periods of heavy physical or mental work, and is of short duration and can usually be reversed by sleep and relaxation, CCOHS says. Chronic fatigue syndrome is a constant, severe state of tiredness that is not relieved by rest.

According to Dawson, the first factor to address is changing the culture around fatigue, fostering a work environment where fatigue is not seen as weak, shameful or a disciplinary problem. In addition to addressing attitudes, workers also need to understand their own limits and fatigue concerns. Many workers think that they’re getting more sleep than they actually are – a worker might may say and think that they got seven hours, when in actuality they got far fewer.

To help workers understand their own fatigue concerns so that they can be addressed, and make the jobsite safer, Caterpillar has developed two technologies.

Smartband monitors quantity and quality of sleep

The Caterpillar Smartband is a wrist-worn safety technology that measures quantity and quality of sleep and provides the wearer with real-time visibility to their fatigue level. According to Sal Angelone, Fatigue Solutions Consultant at Caterpillar, the Smartband collects and analyzes movement data to identify quantity of sleep, quality of sleep, and timing of sleep and wake cycles for individual users. He said that this data “is further processed using a patented bio-mathematical predictive model to demonstrate the users’ change in performance effectiveness over time. Effectiveness is based on sleep history and circadian time of day and is scored out of 100. A score of 70 or below indicates high levels of fatigue and [poses] a statistically significant increased risk of having a fatigue-related human factors incident.”

According to Dawson, the Smartband is tough enough to withstand the rigours of the jobsite. It is designed to be low maintenance and battery life lasts up to 60 days to ensure that workers won’t have to remember to charge it on a frequent basis.

The Gen 1 Smartband is used primarily as an assessment tool, rather than for real-time feedback to the supervisor, but there are plans to expand its capabilities.

Caterpillar Safety Services is currently reviewing a Gen 2 band which is designed for real-time monitoring and predictive monitoring. Like the Gen 1 band, the Gen 2 band will allow the wearer to see a real-time effectiveness score. With the Gen 2 band, the supervisor will be able to review current effectiveness scores as well as predictive scores – what an individual’s score might look like near the end of the shift. Angelone said that this visibility will allow supervisors to focus on risks within shifts.

Privacy of users’ data is a concern addressed by Caterpillar. Dawson said that all data is kept confidential and pooled together by Caterpillar to be provided to management as a group data set. A Caterpillar Safety Services expert can then contact an individual to discuss their findings and confidentially address specific fatigue concerns. The data can be used to flag sleep problems, such as sleep apnea, which contribute to fatigue. When the anonymous compiled data is sent to management, they can use modelling tools to analyze the data, looking at productivity, absenteeism, turnover, health care cost and more to measure the global impact of fatigue.

In-cab driver safety system

The second piece of technology that Caterpillar is offering to combat fatigue is the in-cab Driver Safety System (DSS). When installed in a vehicle, the DSS camera faces the operator and monitors facial characteristics. It looks at eye closure duration and head pose by measuring 24 points on the driver’s face. When an event is detected, the system sounds an audible alarm and rumbles the seat. Fatigue events are logged and sent to a Caterpillar data centre to classify and confirm the event. Caterpillar experts analyze the data and provide recommendations to the organization.

In addition to making the jobsite safer, there is indication that reducing fatigue can reduce wear on equipment. Dawson said that with the DSS in place, one group saw a 13 percent reduction in some vehicle codes – such as hard shifting, abusive shifts, hard braking, driving with the truck body up and so on. Currently, the most common application where DSS is in use is in haul trucks on mine sites.

Changing the workplace culture

“We have to do a few things to make sure people actually accept [the technology], and use it properly,” said Dawson. “So we have a formal system of change management where we go and provide information to the people who are going to be exposed to that technology. We set up some policies, procedures around what’s going to happen with the data, what we are going to do if someone has a fatigue event or they are at high risk.”

Caterpillar Safety Services does on-site training on the use of the Smartband and DSS, and on the attitude toward safety within the organization. When a new piece of technology, especially a camera, just shows up on a jobsite without explanation, workers can understandably become suspicious – which often results in tampering events. When introducing new technology such as the DSS to the jobsite, Dawson said there is a significant drop-off in tampering when transparency and education accompanies the technology.

Caterpillar Safety Services Leadership Workshops cover fundamental principles for fatigue risk management and present strategies to reinforce a workplace culture that is committed to eliminating risk and complacency surrounding fatigue.

“The notion that you can eliminate fatigue is not realistic,” Dawson said. “As long as you have people driving long hours, working through the night, odd shifts, they’re going to get tired, but if we catch it, we can mitigate it and manage it.”

The Gen 1 Smartband.

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