Canadian Occupational Safety

January/February 2020

Canadian Occupational Safety (COS) magazine is the premier workplace health and safety publication in Canada. We cover a wide range of topics ranging from office to heavy industry, and from general safety management to specific workplace hazards.

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Page 17 of 27

18 Canadian Occupational Safety W ork fatigue has caused or contributed to some of the most serious and well- known disasters of the last few decades. The Space Shuttle Challenger incident, which killed all seven crew members in Janu- ary 1986, was due in part to human error and poor judgment caused by sleep loss and shift work during the early morning hours, according to an official report. Lack of sleep may have contributed to the explosion at the Chernobyl Nuclear Power Plant, in 1986, which was caused by human error and occurred just after mid- night. Two plant workers were killed in the incident, and there were 134 subsequent deaths from radiation poi- soning. The Three Mile Island nuclear plant incident (1979) and the Exxon Valdez oil spill (1989) have also been attributed to sleep-related errors in performance or judgment. When workers are fatigued, the risk of making mistakes is significantly increased. Fatigue is a hazard for all workers but especially for high-risk workers, including shift workers. Yet, fatigue is often difficult to identify in the workplace. New kinds of technolo- gies promise to help safety managers and workers become more aware of fatigue to reduce the incidents and injuries it causes. "Studies have shown that lack of sleep acts as an impairment — and it affects safety," says Desira Rostad, busi- ness manager at the Regina-based Safety Association of Saskatchewan Manufac- turers (SASM). "There are people who have shift work or night work, drivers who may work extended hours or who are on call. When schedules are always changing… it has a negative effect on their sleeping pattern. That adds to the fatigue in the workplace." Almost 30 per cent of Canadian workers report being fatigued most days or every day during a typical workweek, according to The Confer- ence Board of Canada. Among workers at highest risk are those who work in mining and in commercial truck- ing. In fact, the Canadian Council of Motor Transportation Administrators has stated that 20 per cent of motor vehicle collisions are linked to fatigue. Fatigue may be the result of lack of sleep, shift work, prolonged mental or physical work and long periods of stress or anxiety. Lack of sleep can be caused by anxiety, taking certain medi- cations, health problems (including depression and sleep apnea) and poor sleep habits. Environmental factors can also pro- mote fatigue, including dim lighting, limited visual acuity, high tempera- tures, high noise and high comfort. Performing tasks that are repetitive, difficult, boring or monotonous can also increase susceptibility to fatigue. Studies have shown that when workers have slept for less than five hours before work or when they have been awake for more than 16 hours, their chance of making mistakes due to fatigue is greatly increased. Workers should get at least between 7.5 and 8.5 hours of sleep per day. Lack of sleep decreases memory and decision-making ability; reaction time; ability to do complex planning; com- munication skills; productivity and performance; attention and vigilance; and the ability to handle stress. FATIGUE TECHNOLOGIES Fortunately, there are many new technologies on the market to help employers reduce the negative effects of fatigue in their workplace. One such technology, made by Fatigue Science, uses a "biomathematical" fatigue model, called SAFTE, and computer algorithms to predict a worker's fatigue impairment throughout the day, says David Trotter, senior vice-president, sales and marketing at Vancouver- based Fatigue Science. Before going to sleep each night, a worker puts on a wristband or "Read- iband." The wearable tracks when the person goes to sleep, how often they awaken during the night and how much they move around and when they wake up. Data is first collected over a period of days, weeks or months. That his- toric sleep data, along with other factors such as the individual's cir- cadian rhythm and time zone (an indication of the amount of light a person gets), are then analyzed by the SAFTE model and algorithm to come up with a prediction of the worker's fatigue throughout the day ahead. It indicates fatigue "curve" — the peaks and troughs that occur during the day. Fatigue level is indicated by a "Readiscore" — a number between zero and 100, where 100 represents full cognitive ability and optimal reac- tion time. "If someone has a Readiscore of 70, that means they have the same cognitive ability and reaction time as someone who has a blood alcohol content of 0.08 per cent. So, obviously, I wouldn't want to drive a vehicle or do anything that is high risk," Trotter says. Creating awareness among indi- vidual workers is one of the main benefits of the technology, he says. It also gives them information to decide when they will do certain tasks; per- forming high-risk tasks when they know their cognitive ability is at a good level and saving other tasks for times when they are tired. Workers can also receive alerts and push notifications. "You can get an alert to your phone saying, 'Hey, 60 minutes from now, you're going to be highly fatigued, take caution.' That gives the worker the chance to take a rest, if possible, or they may want to have a cup of coffee," Trotter says. In some jurisdictions, and if the company has the employee's approval, it may also be possible for a manager to see a worker's data and intervene, moving a task to a different time of the day when the worker is expected to be less tired or even getting workers to exchange tasks. "What our employers are not doing is they're not generally using it to disqualify people from working. It's not a negative, punitive thing to an employee. It's much more about how do you adjust workflows over time so that people are in a more rested state," Trotter says. For organizations, the technology provides information on the cumula- tive fatigue occurring in a particular shift or location. This data can lead them to look for something in their shift patterns or in their employees' commute, for example, that they can adjust to reduce their fatigue risk. "We've had employers that will adjust work hours. They might adjust [remote] workers' sleeping quarters; for example, you put them in a hotel that is quieter and has blackout. There are lots of things they may do. They may also recognize that there's a cer- tain portion of their workforce that may have a clinical sleep issue as well," Trotter says. The key industries for Fatigue Sci- ence are mining, construction, oil and gas and, more recently, manufacturing. The company has also found a market for its technology in non-industrial organizations: in the military and high-performance sports teams. VISUAL TESTING An alternative fatigue technology measures cognitive impairment and alertness by workers' ability to do a brief, game-like test before starting a shift. Two brands available now are Aware4Duty, made by Aware360, and Predictive Safety's AlertMeter (which is distributed by SASM). The test is based on the psy- chomotor vigilance task (PVT), a sustained-attention, reaction-timed task that measures how fast sub- jects respond to a visual stimulus, which was used on the International Space Station by crew members to identify when their performance capa- bility was degraded by fatigue-related conditions. "It's similar to a brain game or memory game. The worker is shown a series of shapes and asked to iden- tify whether any shape is different from the rest or whether they are all the same," says Garrett Desruis- seaux, senior product manager at Calgary-based Aware360. Workers do the test on their smart- phone or tablet. While they are doing a By Linda Johnson WORKER FAT GUE New technologies help safety managers identify employees whose lack of sleep endangers both themselves and others

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