Accumulated (chronic) fatigue is defined as fatigue from which normal rest does not produce recovery. Accumulated fatigue is often caused by extended periods of stress with inadequate recovery periods, which results in decreased productivity, compromised immune function, and reduced alertness. Fatigued workers perform poorly, behave carelessly, tolerate greater errors and become inattentive. Chronic fatigue often results in increased stress, which may present itself through certain behaviorial and physiological indicators, such as those described below:
 
 

• Decreased motivation and low morale
  
•  Increased irratability and depression
  
• Confused, poor problem solving
  Poor abstract thinking
  poor attention/decisions
  poor concentration/memory 
    
   
• Altered state
  A marked increased or decreased awareness of surroundings  
   
• Physical reactions (any of these symptoms may indicate need for medical evaluation. When in doubt, contact a medical professional)
  Chills
  Thirst
  Nausea
  Fainting
  Twitches
  Vomiting
  Dizziness
  Weakness
  Chest pain
  Headaches
  Elevated blood pressure
  Rapid heart rate
  Muscle tremors
  Profuse sweating
  Difficulty breathing 
   
• Extreme emotional responses
  Fear
  Panic
  Intense anger
  Emotional outbursts
  Feeling overwhelmed
  Loss of emotional control
  Inappropriate emotional response   
   
• Social/behavorial changes
  Withdrawn
  Antisocial acts
  Erratic movements
  Change in speech patterns
  Change in usual communications
  Alcohol or substance abuse 
  
• Recommendations for chronic fatigue/stress are:
  Take longer periods of rest/recovery
  Ensure that workers are adequately rested before they begin workshifts
  Slow the work pace to a moderate level on physically demanding tasks
  Provide periodic rest breaks to allow physical and mental recovery
  Alternate between heavy and light tasks
  Change assignments to prevent boredom
  Provide breaks, naps, or time off after tasks have been completed
  Eat well-balanced meals regularly, with energy supplements during periods of high exertion.
  Maintain hydration
  Ensure workers maintain good personal hygiene
  maintain high standards of physical fitness and work capacity
  Seek medical attention when in doubt of symptoms
  In extreme cases, personnel may need to be relieved of their duties

For more safety tips from the Federal Fire and Aviation Safety Team, visit its Six Minutes for Safety section at www.nifc.gov.