This website does not use cookies. Read Privacy Policy here.
Beville Engineering Logo

Do You Know How Tired You Are?


Fatigue is a key issue with safety-critical jobs that must be performed 24-hours a day. Recent research on fatigue in over-the-road truck drivers has disturbing implications for the process control industries. A field measurement of driver alertness hypothesized that self-assessment of fatigue by the drivers and time to collision (separation from vehicles in front of them) would be valid sensitive measures of fatigue, but the data showed otherwise (Belz, S.M., Robinson, G.S., & Casali, J.G. “Temporal Separation and Self-Rating of Alertness as Indicators of Driver Fatigue in Commercial Motor Vehicle Operators, Human Factors, Vol. 46. No. 1, 2004, p154-169).

The authors found that the drivers exhibited driving without awareness (DWA) followed by a sudden onset of fatigue-related symptoms. Contrary to simulator studies, fatigue was not preceded by a multitude of symptoms/indicators, but came on rapidly. The implication for any safety sensitive position is that, by the time the individual feels fatigued, their performance may already be severely compromised.

Copyright © 2004 Beville Engineering, Inc., All Rights Reserved

For further information, visit the links below.

| Alarm & Display System Analysis Overview | Alarm Management | Display Design | Alarm & Display Design Seminar | Beville Shape Calculator -Excel download | Alarm Distribution Estimator -Excel download |


Article Published By
Consortium Reports New Findings on Alarm Rates Automation World
How Many Alarms Can An Operator Handle Chemical Processing
Impact of Alarm Rates and Interface Design on Operator Performance Automation World
Operator Interfaces: Moving from Comfortable to Most Effective Automation World
Operator Performance as a Function of Alarm Rate and Interface Design


This year's Fall meeting for the Center for Operator Performance will be October 24-26 in Corpus Christi. For more information, please contact Lisa Via. Guests are always welcome!


Our summer newsletter is now available. Click here!

Take our short survey on operator span of control. Click here (new window)

David Strobhar's book, "Human Factors in Process Plant Operation," is now available in both hardcover and Kindle e-book.

Copyright © 1996-2019 Beville Engineering, Inc. All rights reserved. (937)434-1093.