Which information should an operating procedure include for a critical process step? (Select all that apply)

A comprehensive operating procedure for a critical step must go beyond normal targets to ensure safety. It must define the safe operating limits (E) which are the boundaries for key process variables. The procedure must also clearly state the consequences of deviating from these limits (B) to emphasize the importance of control. It must detail the required actions for normal operation (C) and specify the corrective actions to take if a deviation occurs (D). This ensures operators can maintain control, understand risks, and respond effectively to upsets, which is a core requirement of Process Safety Management (PSM).

A. Only the normal production target: This is insufficient for safety. Procedures must include safety limits, consequences of deviation, and corrective actions, not just production goals.

1. U.S. Occupational Safety and Health Administration (OSHA), 29 CFR 1910.119, "Process Safety Management of Highly Hazardous Chemicals," Section (f)(1)(i)(D), which requires operating procedures to include "Operating limits," specifying "(1) Consequences of deviation; and (2) Steps required to correct or avoid deviation."

2. Center for Chemical Process Safety (CCPS), "Guidelines for Writing Effective Operating and Maintenance Procedures," AIChE, 1996, Chapter 3, Section 3.3.4, "Limits, Consequences, and Corrective Actions." This section details the necessity of including safe operating limits, the consequences of exceeding them, and the specific steps to correct deviations.