Which terminology describes the level of adherence expected in SOPs?

The term "shall" is used in the context of Standard Operating Procedures (SOPs) to indicate a mandatory requirement. It establishes a clear expectation that the procedures outlined in the SOP must be followed without exception. When "shall" is utilized, it implies a legal or procedural obligation, ensuring that personnel understand that adherence to the SOP is critical for safety, compliance, and operational consistency.

In contrast, the other terms carry different implications. "Must" can also imply a requirement but is often more associated with legal obligations in some contexts. "Should" indicates a recommendation rather than a requirement, suggesting that while following the SOP is advisable, it is not strictly necessary. "Could" implies a possibility or an option, which does not convey a necessity and is not appropriate for defining the level of adherence expected in SOPs. Therefore, "shall" is the most precise terminology for denoting obligatory compliance in this context.