Normal Operating Limits Ranges

Procedures are typically designed for situations in which operations occur as normal.

However, situations arise in which divergence from normal operations occurs, and procedures must be written so as to address these (Scholtz & Maher, 2014).

Procedures must identify and explain the limits and ranges for normal operations of a process for operators to identify, prevent, and correct divergences (Cruz-Guerra & Cruz-Gomez, 2002).

Procedures must include what the normal operating limits and ranges are, how to avoid divergences from the limits and consequences if they do occur, and how to regain normal operating status if a divergence occurs (Cruz-Guerra & Cruz-Gomez, 2002).

Since divergence from the limits can cause abnormal situations which are often high-stress events, the procedures should be developed with this in mind, using clear, concise language (Crossley & McNamara, 2008).

Common practice for panel operators is for Alarm Objective Analyses (AOAs) to be contained in a database for every tag in their accessible unit, which is easily accessible on the computer interface (e.g., right clicking the mouse from the control panel). These include all of the information discussed in this section.