Though most shiftworkers are focused on getting sleep, time and resources are being expended on how to keep people awake and perhaps even forgo sleep completely.

Obviously, being alert at work and while driving is critical. Fatigue and lapses in alertness greatly increase the risk of errors and accidents and these exact a huge cost in accidents and medical care. Workers, therefore, are encouraged to get quality sleep in sufficient quantities to ensure that they remain alert and safe.

In some occupations, however, the need to be alert extends beyond the usual 8 or 12 hours of a shift. International and military pilots fall into this category. Unusual efforts are made in these instances to ensure that they maintain alertness and in the case of US military pilots, amphetamine use has been endorsed. Currently, the US military is also experimenting with the possibility of staying awake for a week at a time. This is an effort to entirely overcome the body’s need for sleep and the restorative effects it offers.

Is it possible that shiftworkers in more ordinary circumstances will be required to undertake the same extraordinary measures to maintain alertness? Perhaps not yet. We have not yet been able to overcome our need for sleep, as was shown by the soldiers in the Iraqi war who were subjected to long periods of sleep deprivation and who resorted to random napping to compensate. However, for the first time a drug has been approved in the United States for use in overcoming sleepiness associated with shift work sleep disorder.

This measure indicates that we are focusing our interventions away from finding the sources of the sleepiness and providing strategies to promote sleep. Instead, we are implementing strategies that simply overcome the sleepiness. Most shift workers are familiar with strategies for maintaining short term alertness, but is it advisable, in the long term, to maintain alertness through these methods? Or should getting enough sleep still be the best answer for ensuring alertness?

The standard employment contract used to offer ‘permanent, full-time’ work with a segment of the workforce working part-time. More recently, another category of employment has become more common. This category is generally referred to as ‘flexible’ work hours, though other terms like ‘casual,’ ‘irregular,’ ‘on-call’ and ‘overtime’ refer to similar arrangements. Those who are working a flexible schedule may be working less than full-time hours, the same as full-time or, in many cases, more than full-time hours.

A flexible work schedule can be determined by the employee and may include job sharing and shift trading. On the other hand, a flexible work schedule can be determined by the employer, and in this instance, employees are required to work as determined by the employer and have little or no control over their work schedule. This practise has become much more common as organizations attempt to control their labour costs. However, the consequences for employees who are subject to employer-based flexibility can be severe.

A review of data in Europe found that “longer and ‘irregular’ working hours are in general linked to lower levels of health and well-being; moreover, low (individual) flexibility and high variability of working hours (i.e. company-based flexibility) were consistently associated with poor health and well-being, while low variability combined with high autonomy showed positive effects.” The report further states that “individual flexibility alleviates the negative effects of the company-based flexibility on subjective health, safety and social well-being.”

If you would like to know if your shift work schedule meets ‘best practice’ criteria, call us about providing a Schedule Clinic.

In their paper “Managing fatigue: It’s about Sleep” (Sleep Medicine Reviews, 2005, 9) Drew Dawson and Kirsty McCulloch present a case for “shift(ing) away from prescriptive HOS (hours of service) approaches to one in which fatigue is no longer managed as an industrial or labour relations issue but rather, as part of an organization’s overall SMS (safety management system)”.

They propose a Prior Sleep/Wake Model arguing that “fatigue is better estimated from prior sleep/wake behavior than from patterns of work.” This model requires a determination of the amount of sleep had in the last 24 hours, the amount of sleep had in the last 48 hours and the amount of time awake from waking to the end of work.

Citing related research, they conclude that general parameters for this model would be as follows:

If an individual has had less than 5 hours of sleep in the last 24 hours and less than 12 hours of sleep in the last 48 hours as well as having been awake for more hours than the total sleep time in the previous 48 hours, than they would be considered at risk for a fatigue error or accident.

Though they set these out as general parameters, they caution that for some tasks and in some circumstances, these may not be adequate or may be over cautious. More industry and task-specific research needs to be done to determine more specific guidelines

Strategies for Health and Safety

Provide education about fatigue and how to recognize it. Include all employees, be they shift workers or regular day employees.

Ensure that your organizational culture supports safety, not just in word, but in deed as well. Ensure that staffing levels are optimum and that overtime is minimized.

All workplaces will experience accidents, errors and omissions of some magnitude from time to time. Many of these, upon investigation, will be found to be the result of sleep deprivation and fatigue, even though the official categorization may be ‘human error.’

In transportation and health care, investigations subsequent to any accident or error usually give consideration to the possibility of sleep deprivation or fatigue as these sectors are known to have high rates of both. However, the investigation of all accidents and errors in the workplace should give consideration to the possibility of sleep deprivation or fatigue as a root cause of the accident or error. This is because many ‘human error’ accidents are the result of poor judgment and reasoning, failure to attend to information or inattention. All of these can be the result of sleep deprivation and fatigue.

Consider the example of a bartender who, at the end of the late shift, goes to restock the coolers. While lifting the cartons of bottles, he loses his balance and falls, causing injury to his back. On the surface, this would seem to be a pretty straightforward incident. However, one should also consider how much the employee was lifting and his reasoning in deciding how much and how to lift. If the employee was extremely fatigued, he may have made an error in judgment that caused him to attempt lifting more than was safe. Even if the load was one that he was accustomed to handling, his fatigue may have decreased his capacity for lifting the load.

Strategies for Health and Safety

Employees need to learn about the behaviors associated with sleep deprivation and fatigue and how these can get played out in their work. Employees also need to recognize when they are sleepy and fatigued and recognize that they may not be able to work with the same effort that they would expect in a more refreshed and alert state.

If you are investigating a workplace error or accident and you wish to determine if sleep deprivation or fatigue were at play, you will want to consider the following:

How many hours had this employee been at work? Research has shown that after 16 hours, the fatigue, and therefore, the risk, rises markedly.

How many hours had this employee been awake prior to coming to work? The longer this time, the higher level of sleepiness and fatigue one would expect.

How much sleep did this employee get in the day or week leading up to this day? A variety of personal and/or work circumstances can lead to minimal sleep for a lengthy period with the resulting high level of sleep deprivation.

Is this employee suffering from an undiagnosed sleep disorder? Some polls suggest that a majority of those with sleep disorders do not even realize they have a disorder much less get treatment for it. Undiagnosed sleep disorders result in high levels of sleepiness day and night.

Has this employee had any near misses in the last several weeks or months leading up to this day or have any other employees observed sleepiness in this employee?

Strategies for Health and Safety

Managers, occupational health and safety professionals and risk managers should be thoroughly versed in the behaviors associated with sleepiness and fatigue. This will allow them to recognize those employees and times of the day or night when they need to be particularly vigilant so as to prevent errors and accidents.