Ever since the dawn of time, humans have been hardwired to work during the day and sleep at night.
Yet millions of Americans earn their paychecks by working schedules that are at odds with the body's biological clock.
They're called shiftworkers.
While many of us think of shiftwork in terms of the midnight-to-8 shift, experts have expanded the definition to include just about any schedule that's outside the 9-to-5 routine. That means if you work rotating shifts or have a schedule that involves long, irregular hours, you're a shiftworker.
"No matter how you slice it, shiftwork is covering around-the-clock in some permutation of 8-, 10- or 12-hour shifts, as opposed to the office worker who works 9 to 5," explains Bill Sirois, senior vice president and chief operating officer of Lexington, Mass.-based Circadian Technologies Inc.
If you have employees whose schedules fit the definition of shiftwork, experts believe they're at a higher risk of injuries, illnesses and accidents than your dayworkers.
On top of that, shiftworkers wrestle with unique challenges, such as the stress of trying to meet family and social obligations existing in the 9-to-5 world.
In terms of your company's bottom line, each shiftworker in your facility is costing you nearly $8,600 more per year than each dayworker, Circadian estimated in a recent study.
That figure which Sirois believes is "an extremely conservative number" includes the extra costs of lost productivity, absenteeism, turnover, health care and safety and accidents associated with shiftworkers.
Now, multiply $8,600 by the Bureau of Labor Statistics' estimate of 24 million shiftworkers in the United States, and it's a nearly $206 billion financial hit for companies across the country, according to Circadian.
The good news is there are some simple, straightforward strategies you can employ to minimize the safety and health risks and concomitant costs that come with shiftwork.
But first, let's look at why shiftwork schedules come with so much baggage.
Software that's as Old as Mankind
For as long as the earth has rotated on its axis once every 24 hours, we have risen and set with the sun.
From this basic fact of life comes our understanding of circadian rhythms. Circadian rhythms (circadian is Latin for "about a day") control virtually every human biological function, including our body's clock, which determines when we're alert and when we're tired.
"Basically we're programmed for being active in the day and for sleeping at night," explains Mark Rosekind, Ph.D., founder, president and chief scientist of Cupertino, Calif.-based Alertness Solutions.
Sirois puts it this way: "Think of it as hardwired software that goes back to the beginning of humankind."
So, for millennia we've had this software in our brain telling us to wake up when the sun comes up and to go to bed when the sun sets. Then along comes electricity, the light bulb, the industrial revolution ... and before we know it, people are working night shifts en masse.
However, our biology never changed.
"When some guy went and invented the light bulb, we made it possible to live and work around the clock," Sirois quips. "But we've not yet broken the genetic code."
In today's 24-hour economy, shiftwork is more common than ever.
That's because jobs that involve twists such as early start times, unplanned work extensions, daytime sleep periods, time zone changes and on-call or reserve status disrupt the body's circadian rhythms in the same ways that the classic midnight-to-8 shift does. With that in mind, Rosekind estimates there could be as many as 83 million people in the United States who fit the definition of shiftworker.
It Starts with Sleep
Many of the safety and health risks that shiftworkers encounter begin with sleep or lack thereof.
Because shiftworkers are on schedules that run counterclockwise to the body's circadian rhythms, they often struggle to get a good night's or day's sleep.
An example would be the nightworker who finishes his shift at 7 a.m., goes home, falls asleep and then wakes up in an hour or two because his biological clock tells him: "It's daytime. Wake up!"
Of course, that same worker could wake up prematurely for a variety of other, external reasons from the phone ringing to a neighbor cutting the grass to a child wanting to play catch.
Sleep deprivation and chronic disturbances of sleep such as obstructive sleep apnea a potentially life-threatening sleep disorder in which breathing is briefly and repeatedly interrupted during sleep are common among shiftworkers. According to Rosekind, research has shown that shiftworkers average about 5 hours of sleep; Sirois put the number at about 5.5 hours a night.
But even when shiftworkers are sleeping, they're getting poor-quality sleep, Sirois adds.
With inadequate sleep comes fatigue, and with fatigue, Sirois explains, workers experience a drop in their:
- Ability to maintain vigilance and attention levels;
- Awareness and perspective of the environment around them;
- Cognitive and logical reasoning skills;
- Reaction times; and
- Motor coordination skills.
If that sounds like someone who is drunk, that's because there is scientific evidence indicating that people who are overly tired are legally intoxicated, according to Sirois.
Rosekind, in fact, points to a study that suggests that workers who get 2 fewer hours of sleep than they need are likely to perform at the same level as someone who has had two or three 12-ounce beers.
Chronic sleep loss also can lead to fatigue-induced mental lapses known as microsleep and automatic behavior syndrome, which have "caused countless human-error related incidents and fatalities, even with experienced and senior workers with outstanding safety and performance records," explains Sirois. Such lapses are thought to have played a role in the Exxon Valdez and Three Mile Island accidents as well as "countless truck, bus and train accidents."
Shiftworkers not only pay a price for sleeping when they're supposed to be awake, but also for working when they're supposed to be sleeping what Rosekind calls a "double whammy."
If you're working from the hours of about 3 a.m. to 6 a.m., you're working during the lowest point on the body's circadian clock when your body and mind are least able to function. These are the times of our lowest core body temperature, lowest blood pressure and maximum melatonin in our system.
During that time window, there are 15 times more industrial and transportation accidents and workers are 15 times more likely to be involved in a car accident than any other time of day, according to Sirois.
To stay awake during their circadian lows, many shiftworkers resort to countermeasures such as coffee and other stimulants such as amphetamines. This creates another double whammy of sorts: When the shift is over, some shiftworkers find they need to drink alcohol or take sleeping pills just to fall asleep.
It's also not uncommon for shiftworkers to use food and nicotine as coping mechanisms, Sirois explains. In addition to copious amounts of coffee, shiftwork staples tend to include things like donuts, pizza and cheeseburgers.
While pizza might be comfort food to a lot of folks, it's not to the stomach. The stomach which is programmed by our circadian rhythms to secrete digestive acids and enzymes during the day shuts down at night.
So, when shiftworkers shove down that piece of pizza at 4 a.m., they're not only making themselves sleepier by eating junk food but they're also shocking their digestive systems. It's no surprise, then, that Circadian Technologies' surveys have found that up to 50 percent of shiftworkers take antacid or prescription medication to deal with heartburn or indigestion.
It's also easy to see why shiftworkers are at a greater risk of gastrointestinal diseases, obesity, mental health disorders, cancer and cardiovascular problems such as heart disease.
Finally, shiftworkers wrestle with the added stress of trying to be parents, spouses and friends to those who operate in the 9-to-5 world. Glenn McBride, a Lake Jackson, Texas-based consultant and author of "The 12-Hour Schedule Lifestyle: Secrets of 12-Hour Living for Shiftworkers," explains that raising children can be "the greatest negative stress" of shiftwork.
A Comprehensive Program
Because of the diversity and complexity of work forces and work settings, Rosekind cautions that there is no magic bullet to managing the sleep and circadian disruptions that come with shift schedules.
Instead, he advocates a comprehensive program that includes four main elements: education, alertness strategies, scheduling and healthy sleep.
Rosekind also urges employers to make sure their program is grounded in sound sleep/circadian science and to make sure their program is codified in explicit company policies.
For example: "If you want to have a napping program, you have to have a policy," Rosekind says. "In most places, if you sleep on the job, you get fired."
Circadian Technologies' Sirois recommends a step-by-step approach to mitigating the EHS risks of shiftwork.
That approach includes:
- Conducting a shiftwork opportunity assessment;
- Developing a strategic plan;
- Building consensus for the plan among stakeholders; and
- Rolling out the shiftwork countermeasures listed in the strategic plan. (Some examples are provided in the sidebar.)
"It's a very simple equation," Sirois concludes. "We humans are designed to sleep 8 hours each night and function for 16 hours during the daytime and evening hours typically between 7 a.m. and 11 p.m. When we disrupt that equilibrium, there usually is a price to pay."
Sidebar: Simple Shiftwork Strategies
We weren't built for shiftwork, so it's up to employers to manage the risk factors that come with the territory. Educating your shiftworkers in the following areas can help you make a positive impact on their safety, health and productivity.
Caffeine management: Caffeine is a powerful stimulant, but drinking too much coffee or drinking it late in a shift can interfere with sleep. Encourage shiftworkers to use coffee in moderation and to drink coffee at the front end of the shift; they should switch to decaf or juice for the rest of the shift.
Diet: Encourage shiftworkers to "graze" through their shifts on low-fat, low-sugar snacks such as low-fat crackers, popcorn, pretzels, tossed salads and celery and carrot sticks with low-calorie dip.
Exercise: A 20-minute aerobic workout can delay by 3 to 4 hours the energy/alertness drop that workers experience during their circadian lowpoint and can help workers sleep when their shift is over, according to Sirois. That's why Entergy Corp.'s Pilgrim Nuclear Power Station in Plymouth, Mass., has installed aerobic equipment in its facility. "Guys are encouraged to use it if they're feeling a bit down," says Paul Coffey, a project manager at the facility. The facility also has incorporated surveillance walks into the schedules of many of its 125 shiftworkers.
Naps: A 20-minute power nap has been scientifically proven to provide a 4-hour boost in alertness and productivity, according to Sirois. Develop a policy that allows overly tired workers to take short naps with supervisor permission as needed or during breaks.
Scheduling: A growing number of employers are moving away from 8-hour schedules to 12-hour schedules; advocates include author Glenn McBride, who contends that 12-hour schedules, if managed properly, provide more energy, recovery time and quality time with family. Sirois recommends starting morning shifts around 7:30 or 8 a.m. to accommodate the circadian rhythms of the most workers. For rotating schedules, clockwise rotations from days to evenings to nights are user-friendly; counterclockwise rotations "are extremely stressful," Sirois says. Any restructuring of schedules only will succeed with employee involvement and input.
Training: Incorporate education on the basics of sleep, circadian rhythms and other shiftwork issues and strategies into training. Bayer Material Sciences of Baytown, Texas, hired Circadian Technologies to provide train-the-trainer classes for six of its employees, and now the facility provides mandatory training for its newly hired shiftworkers and newly promoted shift supervisors as well as voluntary training for all employees, explains site Human Resources Director Shirlyn Cummings. Training covers sleep management, nutrition, family relationships and other tips and guidelines for managing a shiftwork lifestyle. Family members, spouses and friends are encouraged to attend.
Work environment: Changes to the work environment can reduce physical and mental fatigue. Bayer Material Sciences, for example, recently lifted a 35-year ban on music in its 15 or so control rooms. Cummings says the previous anti-music policy "was based on the belief that additional noise or music would be a distraction," but recent research shows that "within certain parameters, music actually is a stimulant." Other musts in a work area include bright, full-spectrum lighting; bright colors on the walls; good airflow; and temperature control, as the human brain works best in a 68- to 70-degree environment.