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Objective(s)Explain How Sleep Cycles, Hours and

Circadian Rhythm Disturbances Can Develop Into Short- Term, Cumulative and Chronic Effects on Performance and contribute to accidents.

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Why Should We Care ?31% of All Drivers Have Fallen Asleep at

the Wheel Sometime During Their Lifetime

56% of Shift Workers Have Fallen Asleep on the Job

55% of Adults Stated They Experienced Daytime Drowsiness.

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The Human Toll100,000 Fatigue Related Collisions Per

Year1,544 Fatigue Related Deaths Per YearImagine:

A Boeing 727 Crashing Every Six WeeksOr the Titanic Sinking Once a YearOr an Oklahoma City Bombing Every Month

and a Half.

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Who Pays the Costs?

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Where Are We Now?In the Past 20 Years: 158

Hours Added Annually to Our Schedule

Since 1969: 241 Hours Added Yearly to Working Mothers’ Schedule

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What is Fatigue?Fatigue Is a Complex State Characterized

by a Lack of Alertness and Reduced Mental and Physical Performance, Often Accompanied by Drowsiness

Misconception: Fatigue Is Not Just Falling Asleep.

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Fatigue Signs and SymptomsForgetfulnessPoor CommunicationImpaired Decision -

Making SkillsLack of AlertnessSlow Reaction TimeMicrosleep

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Fatigue Signs and Symptoms (cont’d)

Withdrawn BehaviorDepressedMoodyQuick to AngerNo Sense of HumorLack of InterestAlways Tired

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Factors That Affect Fatigue

Time of Day/Circadian EffectsSleep DisordersEnvironmental ConditionsNutritionPhysical FitnessDrugsHealthAge

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Mental Fatigue

Tired and Drowsy Due to Loss of Sleep

Loss of Concentration And/Or Alertness

Diminished Levels of Creativity and Logic.

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Physical Fatigue

A Decrease in Physical Performance

A Feeling of Muscle Discomfort or Soreness

Lack of Energy.

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SLEEPA Highly Complex Physiological Process During Which the Brain and Body Alternate Between Periods of Extreme Activity and Quiet, but Are Never Shut off.

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What Do We Know?Sleep Is a Vital NeedOne-third of Our Life SHOULD BE Spent

AsleepThe Average Person Needs at Least 8

Hours of Uninterrupted SleepSome People Mistakenly Feel They Don’t

Need a Full Night’s Sleep.

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Accumulating a Sleep DebtSleep Loss Is Cumulative and Builds a DebtMost People Get 1 to 1.5 Hours Less Sleep

Per Night Than They NeedPeople whose sleep was restricted to 4 to 5

hours per night for one week needed two full nights sleep to recover vigilance, performance, and normal mood

How Do You Get Out of Sleep Debt? SLEEP!.

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The Two States of SleepState INon-REM Sleep

Physical and Mental Activities Slow

Physical Restoration Occurs

State IIREM: Rapid Eye

MovementExtreme Mental

ActivityMental

RestorationMajor Muscles

Are Paralyzed

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States andStages of Sleep

Effects of Alcohol on SleepBreaks Down Into Sugar and Will

Disrupt SleepEliminates All REM Sleep in First

Half of Sleep PeriodCan Lead to Balancing Act.

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Sleep DisordersChronic InsomniaNarcolepsySleep Apnea Restless Leg SyndromePeriodic Limb Movement Disorder

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Driving Drowsy Affects Performance Like Driving Drunk

19 Hours Without Sleep Is Similar to a BAC of .05%

24 Hours Without Sleep Is Similar to a BAC of .10%.

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0.00%

0.01%

0.02%

0.03%

0.04%

0.05%

0.06%

0.07%

0.08%

0.09%

0.10%

0 HOURS 19 Hours 24 HOURS

Who is Most at Risk?Sleep LossWorking/Operating/Driving

PatternsMidnight Till 0600 amMid-afternoonMany MilesMany HoursMonotony

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Who is Most at Risk? (cont’d) Use of Sedating

MedicationsUntreated Use of

Sedating MedicationsUnrecognized Sleep

DisordersConsumption of

Alcohol.

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Internal Body Clock(Circadian Rhythms)All Animals Have ItIt Runs on About a 24 Hour

CycleAll Human Functions Are

Controlled by It

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Daily Sleepiness and Performance Rhythms

Two Times of Peak Sleepiness Each DayAbout 3 to 5 A.M. About 3 to 5 P.M.

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0

200

400

600

800

1000

1200

MidnightNumber ofCollisions

Biological and Social Effects on Shift Workers

60 to 80% Have Chronic Sleep Problems4 to 5 Times More Likely to Have Stomach

Disorders80% Affected by Chronic Fatigue5 to 15 Times More Likely to Suffer From Mood

Swings and DepressionDivorce and Spousal Abuse Rates HigherDrug and Alcohol Abuse Rates Higher

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Incidents Related to Circadian Disruption

Chernobyl 1:23amBhopal 12:40amThree Mile Island 4:00amExxon Valdez 12:04am.

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Incidents Related to Circadian Disruption (cont’d)

Most Mistakes by Rail Employees 3-5amMost Mistakes by Omission 3-5am

SurgeonsNurses Postal WorkersTelephone Operators.

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What to Expect if You Don’t Sleep

Behavioral Problems PerformanceMood SwingsEventually You WILL Sleep.

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What are the costs of fatigue?

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Where Do You Go to Find the Costs?

Examine Crash Data, Incident Logs Review Workers’ Compensation Claims,

Sick Leave, and OSHA 300 Log For DataReview Overtime, or On-call Status

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The Costs? (cont’d)Consider Fatigue As a Possible

Contributing or Causal Factor in All Investigations

Traffic, Industrial/Workplace, Internal, External Incidents: Review With Fatigue in Mind.

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Keys to ChangeKnowledge of Fatigue Awareness of Fatigue’s Effect on Safe OperationsUnderstanding of Your Workplace Safety Culture.

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QUESTIONS?Contact Risk Management Department: 361-888-

0401Risk Manager: Lance C. Esswein lance.esswein@co.nueces.tx.us

Risk Management Specialist: Martha Sanchezmartha.sanchez@co.nueces.tx.us