How Tired is Too Tired?

Fatigue is a natural condition that impacts every one of us. Whether it’s a mid-afternoon energy slump or a more severe case precipitated by a sleepless night or extended periods of physical or mental exertion, most of us experience some degree of fatigue every day.

When it comes to drowsiness, we all share something else in common: we are terrible at assessing our own level of fatigue. In fact, as we grow more and more weary, we become less and less capable of adequately gauging our level of impairment. All the while we may be putting ourselves, and others, at significant risk. Within mining operations, fatigue is a leading contributor to 60-70% of human error incidents.

We may acknowledge the warning signs that fatigue is setting in – yawning is one – but how do we know when we’re too tired to work safely?

Even when operators know they’re tired, they may be reluctant to tell anyone about it. Our society rewards perseverance and grit, and sleepiness is often regarded as a weakness. No one wants to be perceived as weak, so the stigma of fatigue stymies open communication about an issue that can have severe, even fatal, consequences. Did you know that the incident reports of the 1989 Exxon Valdez oil spill and the 1984 Space Shuttle Challenger explosion – two historic disasters caused by human error – both point to fatigue as a major contributing factor?

The Human Factors Analysis found in Appendix G of the Presidential Commission on the Space Shuttle Challenger Accident states:

“One factor which may have contributed significantly to the atmosphere of the decision to launch is the effect on managers who had several days of irregular working hours and insufficient sleep.”

Sleep debt cumulatively degrades vigilance and attention, slows cognition, deteriorates short-term memory, decreases frontal lobe functions, and increases unpredictable and involuntary sleep onsets or "micro-sleep."

The invisible nature of fatigue risk means many companies can't quantify just much their operations are being impacted – or see how their management systems are contributing to the threat, and perhaps elevating it, shift by shift.

However, accepting and making a commitment to address this invisible threat provides an opportunity to better understand operator performance, positively impact risk mitigation, make efficiency gains, drive cost control and improve the overall health and wellness of our employees.