A hazard evaluation is defined as the identification of individual hazards of a system, determination of the mechanisms by which they could give rise to undesired events, and evaluation of the consequences of these events on health (including public health), environment, and property. These evaluations often use qualitative techniques to pinpoint weaknesses in the design and operation of facilities that could lead to incidents.22 Current requirements exist within the RMP rule to conduct these evaluations. RMP hazard evaluation regulations require, among other things, owners or operators with Program 2 processes to conduct hazard reviews under 40 CFR 68.50(a) that identify:
- The hazards associated with the process and regulated substances;
- opportunities for equipment malfunctions or human errors that could cause an accidental release;
- the safeguards used or needed to control the hazards or prevent equipment malfunction or human error; and (4) any steps used or needed to detect or monitor releases.
Owners or operators with Program 3 processes are required to conduct process hazard analyses (PHAs) under 40 CFR 68.67(c) that address:
- The hazards of the process;
- the identification of any previous incident which had a likely potential for catastrophic consequences;
- engineering and administrative controls applicable to the hazards and their interrelationships, such as appropriate application of detection methodologies to provide early warning of releases (acceptable detection methods might include process monitoring and control instrumentation with alarms, and detection hardware such as hydrocarbon sensors);
- consequences of failure of engineering and administrative controls;
- stationary source siting;
- human factors; and
- a qualitative evaluation of a range of the possible safety and health effects of failure of controls.
The hazard evaluation requirements are key to understanding how to operate safely and prevent accidents and the release of hazardous substances. In developing the initial 1996 RMP rule, the Agency recognized that many workplace hazards also threaten public receptors and that most accident prevention steps taken to protect workers also protect the public and the environment. Consequently, EPA adopted and built on much of the existing accident prevention language from OSHA’s PSM standard, including the process hazard analysis (PHA) language from 29 CFR 1910.119(e). EPA’s understanding of the PHA was based on OSHA’s:23 a PHA analyzes potential causes and consequences of fires, explosions, releases of toxic or flammable chemicals, and major spills of hazardous chemicals.
The PHA focuses on equipment, instrumentation, utilities, human actions (routine and nonroutine), and external factors that might impact the process. These considerations assist in determining the hazards and potential failure points or failure modes in a process. OSHA pointed to detailed industry guidance that serves as the basis for understanding what hazards are widely recognized as threats to safe chemical process operations. For example, the American Institute of Chemical Engineers’ Center for Chemical Process Safety (CCPS) developed the publication “Guidelines for Hazard Evaluation Procedures,” which EPA and OSHA agree generally addresses the most common categories of hazards relevant to facilities that handle hazardous chemicals.
While EPA and OSHA have not explicitly added language in their regulations on certain hazard evaluation elements that were assumed implicit and recognized as hazards among industry, EPA seeks to emphasize that some hazards should be explicitly addressed by facilities to further protect human health and the environment. EPA is not proposing additional regulatory requirements from what already exists in the RMP regulations, rather EPA is proposing adding regulatory text to emphasize that natural hazards and loss of power are among the hazards that must be addressed in hazard reviews and PHAs. EPA is also proposing to emphasize that facility siting should be addressed in hazard reviews, and to explicitly define the facility siting requirement for Program 2 and Program 3 hazard evaluations. EPA seeks to better reflect its longstanding regulatory requirement rather than impose additional regulatory requirements (and potential additional costs) that diverge from the OSHA PSM regulatory requirements. EPA has coordinated with OSHA throughout the development of this proposed rule to ensure the intent of adding specificity to these hazard evaluation requirements is consistent with the intent and meaning of the OSHA PSM standard to avoid inconsistencies between the two regulatory programs.