Mike Harnett, the VP of human factors at Six Safety Systems, was the presenter for the "I'll sleep when I'm dead" session at the Vancouver Regional Construction Association's Construction Leadership Forum on May 5 in Whistler, B.C.
Harnett said that fatigue as a factor within the construction industry is guided by irregular and long hours, timeline pressures, physical and mental demands, a lack of break facilities and equipment factors.
Fatigue is defined as a decreased capacity to perform mentally or physically as a result of a lack of restorative sleep. It is influenced by the time of day and how long you've been awake, and fatigue accumulates. It has a direct long term effect on physical and mental health.
"Only sleep cures fatigue," Harnett said, and it is not the same as drowsiness, which fluctuates.
The more fatigue that's built up, the more drowsiness you'll have.
Circadian rhythms are our built-in body clock, she said, built around a 24-hour cycle and responding to light and dark. They affect alertness, behavior, coordination and emotions. The body temperature curve, controlled by light entering our eyes, dictates how alert we feel. The "post lunch dip" is a natural part of our rhythms and is the reason we get drowsy after lunch.
In the last 100 years, we have reduced our sleep from an average of nine hours to less than seven hours, and 36 per cent get less than six hours. The difference is the invention of electricity. Previously, we got up and went to bed with the sun, and now we pack more "daylight" into our day.
How much sleep is enough is genetically pre-determined, but most require a minimum of seven to nine hours. When you miss out on sleep one can see it the next day, daylight savings time being the best example.
Short sleeping accelerates the aging process of every cell at the DNA level, she said, and there is also a connection to Alzheimer's and dementia to lack of sleep. Obesity and diabetes are also tied to lack of sleep.
"We can put on more weight simply from not having enough sleep," Harnett added.
Chronic sleep loss is also tied to a number of different disease risk factors, including stroke risk, digestive disorders, depression and cancers. Medications also don't metabolize at night in the same way.
Sleep disorders affect 40 per cent of Canadians, including sleep walking, sleep talking, periodic limb movement disorder, and circadian rhythm sleep disorders. There is also a substantial increase in Obstructive Sleep Apnea (OSA) where breathing stops while you sleep. Equipment operators are at the highest risk of OSA, Harnett said.
Fatigue is dangerous, she said, because it can induce automatic behavior syndrome, which is taking actions but not engaging in cognition.
None of the tricks like rolling down the window or turning up the radio does anything but provide a very short term solution. "If this is what's keeping you on the road...get off the road!" she said.
Sleeping solutions include buying a good bed, which stops the transfer of movement. A bedroom should an oasis, and a "no argument" zone. All sources of light should be removed, including televisions. TV is a flashing source of light and the sound aspect also damages sleep patterns. Reading books is better for you than backlit devices like an iPad. Those reading iPads take 10 minutes longer to fall asleep, and have 55 per cent less melatonin. They also felt sleepier the next day. Apple has a "night shift" setting, and Android has a filter, which will change the color temperature of the phone's light to something appropriate to nighttime reading. You can also buy AM/PM bulbs or tunable LEDs which will change with the time of day.
A pre-sleep routine will also help your body to know the cues to fall asleep, such as reading a book or taking a bath. Napping can boost alertness for hours, but naps also have to be structured. Naps should be taken at the same time of day, and naps should be limited to 30 minutes. Once you get past 40 minutes, you go into delta sleep and it's much more difficult to wake up again. A longer nap should be two hours, which takes you completely through your sleep cycle.
When you just can't sleep, get out of bed after 30 minutes and do something calming like reading or watching television. Journaling or sleep apps can also help.
From an organizational perspective, sleep is controllable by workers, and is often equated with laziness or indolence, when in fact it is a sign of a healthy lifestyle. The supervisor's role, if someone suffers from fatigue, is to ensure the problem is addressed, because if it isn't eventually errors will crop up and cause problems in the workplace.
"It's about safety and performance," Harnett said, about the physical and mental ability as well as emotional stability and alertness.
Analyze work schedules and the true cost of overtime, and educate the workforce on fatigue related risks and personal management strategies, she added.