Develop a Human Performance Modeling System for Process Safety Operations


Operators have a crucial role in case of an emergency in a process facility. When an abnormality occurs in the process, the operator has a limited time to take corrective actions before system safety devices shut down the system. It is crucial that system designers and safety professionals know about this required time / time frame before operations are initiated Specific research goals for this project include the following: • Estimating the standard time data for operators to take corrective actions in emergency situations. • Developing an easy-to-use computer based modeling system, to allow design/process engineers to find the standard time required for the operator(s) to respond in emergency situations. Current standard time data for carrying out tasks cover normal cases. However, the time required to take actions in emergency situations is different than normal cases. Because of the possibility of a process incident and danger, operators make corrective actions faster compared to normal cases. Therefore, current standard time data do not meet the requirement for emergency situations. A shorter standard time data for emergency situations needs to be estimated. Standard time data for emergency situations is estimated by using time studies. Various time study methods were introduced and discussed. MODAPTS is a predetermined time standard method and stands for MODular Arrangement of Predetermined Time Standards, and was used in this project because it is reliable, easy to use and consistent. The methodology adopted for the study required observing several emergency case videos. Then the operations are decomposed into basic motions (such as walking, hand movement, bend and arise, etc.) by using a video player's frame by frame feature. The amount of time required to take these basic motions was estimated. These estimated times were then compared to MODAPTS data, which is a predetermined time standard system. By comparing MODAPTS's standard time intervals with those estimated from emergency situations, coefficients have been estimated for the various basic motions (e.g., factors such as 0.9, 0.75, etc.). The estimated coefficient for emergency situations will be used in developing a user-friendly computer based modeling system. After the modeling system is complete, when the user enters tasks in the software, it will access MODAPTS, and take the necessary basic motion times and multiply them with the coefficients determined in this work. Therefore, the time required to do those tasks in an emergency will be provided to the user.

Meeting Name

AIChE Spring Meeting and 8th Global Congress on Process Safety (2012: April 1-5; Houston, TX)


Engineering Management and Systems Engineering

Second Department

Psychological Science

Keywords and Phrases

Computer-based modeling; Corrective actions; Emergency; Emergency situation; Frame features; Hand movement; Human performance model; Human performance modeling; MODAPTS; Modeling systems; Process safety; Required time; Research goals; Safety professionals; Study methods; System designers; Time frame; Time interval; Time standard; Video players; Time and motion study; Plant shutdowns

International Standard Book Number (ISBN)


Document Type

Article - Conference proceedings

Document Version


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© 2012 American Institute of Chemical Engineers (AlChE), All rights reserved.

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