Describing Limitations and Precautions
Limitations inform procedure users of barriers to completion of steps/sections of a procedure and regulatory or site administrative limits (Cruz-Guerra and Cruz-Gomez, 2002).
Precautions inform procedure users of additional issues that may arise when completing a task (e.g.: fire hazards, high temp/pressure fields, high noise level, electric shock, and confined space hazards) and how to reduce exposure to them (CCPS, 1996).
Guideline 1: Limitation Content Within Analysis Document
Common practice is for technical requirements and exceptions/limits of procedure applicability to be included in an analysis document.
Support
In the analysis document, safe upper and lower operating limits should be included as well as relevant requirements and limits of procedure applicability (Cruz-Guerra and Cruz-Gomez, 2002).
Example
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Instead of:
Instead of:
Guideline 2: Limitation Phrasing
Limitations should be written in the passive voice, with no action required.
Support
When an event is coded in terms of the receiver of the action or information, passive sentences are more easily verified (Olson and Filby, 1972).
Example
Use:
Instead of:
Instead of:
Guideline 3: Procedure Precautions Considerations
Common practice is for technical requirements and exceptions/limits of procedure applicability to be included in a limitation section.
Support
When an event is coded in terms of the actor, active sentences are more easily verified. However, when an event is coded in terms of the receiver of the action or information, passive sentences are more easily verified (Olson and Filby, 1972).
Example
Use:
Guideline 4: Equipment Limitations Considerations
Common practice is for specific limits to be included on controlled parameters as well as appropriate corrective actions to return parameters to the normal control band.
Support
Standard operating procedures should include the consequences of deviations from operating limits as well as actions to take if they are exceeded (Cruz-Guerra and Cruz-Gomez, 2002).
Example
Use:
Instead of:
Instead of: