PT Notes
Amendments to EPA's RMP Rule - Natural Hazards and Loss of Power
PT Notes is a series of topical technical notes on process safety provided periodically by Primatech for your benefit. Please feel free to provide feedback.
EPA has proposed several amendments relating to hazard evaluation for Program 2 and 3 RMP-regulated processes. This PT Note addresses:
- Regulatory text additions to emphasize that external events, particularly natural hazards and loss of power are among the hazards that must be addressed in hazard reviews and process hazard analyses (PHAs). Natural hazards include those caused by climate change or other triggering events that could lead to an accidental release. Hazard evaluations must explicitly address standby or emergency power systems.
Further details are provided below.
Natural Hazards
Neither EPA’s RMP rule nor OSHA’s PSM standard currently contain explicit language relating to natural hazards or power loss as factors in hazard evaluation. They were assumed to be implicit and recognized factors in hazard evaluation by industry.
Natural hazards (e.g., extreme temperatures, high winds, floods, earthquakes, wildfires) can initiate events which challenge the safety and operation at hazardous installations. If not properly managed, these hazards can trigger accidents that threaten human health and the environment. Accidents triggered by such events are known as “Natech” (Natural Hazards Triggering Technological Accidents).
EPA notes that some RMP accidents are reported as linked to natural hazards and that climate change is increasing the threat from more severe and frequent extreme weather events, including wildfire, flooding, hurricane storm surge, coastal flooding, tornados, severe thunderstorms, extreme precipitation, and tropical cyclones. EPA believes it must consider the increased risk to RMP facilities and that actions to ensure natural hazards are evaluated and properly managed are critical. Therefore, EPA is proposing to emphasize that natural hazards, including those associated with climate change, should be included explicitly in the hazards evaluated in hazard reviews and PHAs for Program 2 and Program 3 RMP-regulated processes. EPA believes making more explicit this already-existing accident prevention program requirement will ensure the threats of natural hazards are properly evaluated and managed to prevent or mitigate releases of RMP-regulated substances at covered facilities.
EPA notes that emphasizing that some hazards should be explicitly addressed by facilities is not an additional regulatory requirement.
Under the proposed rule, “natural hazard” is defined as:
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Naturally occurring events that have the potential for negative impact including meteorological or geologic hazards. Meteorological hazards include those that naturally occur due to the weather cycle or climatic cycles, and include flooding, temperature extremes, snow/ ice storms, wildfire, tornado, tropical cyclones, hurricanes, storm surge, wind, lightning, hailstorms, drought, etc. Geologic hazards are those occurring due to the movement of the earth and the internal earth forces, and include seismic events, earthquakes, landslides, tsunami, volcanic eruptions, and dam rupture.
Power Loss
Whether caused by a natural hazard or some other event, power loss at hazardous chemical facilities can lead to a variety of negative impacts including equipment outages, process upsets, and process safety incidents involving releases, fires, and explosions. EPA believes that when a facility relies on electrical power for any aspect of its process operations, it is imperative to anticipate how power loss affects the safeguards that prevent releases of hazardous chemicals. Power loss has resulted in serious accidents at RMP-regulated facilities.
EPA has long recognized that loss of power can threaten hazardous chemical processes and cause accidental releases if not properly managed. While EPA did not specifically require power loss to be evaluated for Program 2 and Program 3 hazard reviews and PHAs, EPA and OSHA guidance has referred to it.
OSHA's position is that any engineering control (including utility systems) which does not contain a highly hazardous chemical (HHC) but can affect or cause a release of an HHC, or interfere in the mitigation of the consequences of a release, must be, at a minimum, evaluated, designed, installed, operated (with appropriate training and procedures), changed, and inspected / tested / maintained per OSHA PSM requirements.
EPA believes making more explicit this already-existing accident prevention program requirement to evaluate hazards of the process will ensure the threats of power loss are properly evaluated and managed to prevent or mitigate releases of RMP-regulated substances at covered facilities.
Power failure events may be exacerbated by the frequency and severity of extreme weather events if the impacts of potential power failures are not identified, and control strategies are not implemented. Climate change poses long-term challenges because it affects the frequency, intensity, and duration of weather events that represent the largest source of disruptions to the U.S. electric power grid. New studies have shown that the threat of power loss is increasing for utility customers. Data indicate that more major weather events, such as hurricanes and winter storms, occurred in 2017 than in previous years, and the total duration of power interruptions caused by major events was longer. Therefore, EPA is proposing to further emphasize loss of power in the hazards evaluated in hazard reviews and PHAs for Program 2 and Program 3 RMP-regulated processes.
EPA believes further emphasis on these accident prevention program provisions will ensure that the risk of power failure is properly evaluated and managed to prevent or mitigate releases of RMP-regulated substances at covered facilities. EPA is also proposing to include emphasizing that hazard evaluations address standby or emergency power systems. EPA expects facilities to properly evaluate whether power loss is a hazard to their process and, if so, implement appropriate controls to prevent or reduce that hazard.
EPA is concerned that the threat of extreme weather events has and will be used by some owners or operators to justify disabling equipment designed to monitor and detect chemical releases of RMP-regulated substances at their facility. EPA is concerned that air monitoring and control equipment is often removed from service before natural disasters to potentially prevent damage to equipment or, conceivably, in some cases, evade monitoring requirements and therefore may not become operational again until much later, after the event or threat has passed.
To prevent accidents, RMP owners or operators are required to develop a program that includes monitoring for accidental releases. EPA does not believe natural disasters should be treated as an exception to this requirement. A large-scale natural disaster may threaten multiple RMP facilities in a community simultaneously, leaving communities to endure the direct effects of a natural disaster without receiving warning of associated chemical releases. EPA wants to ensure RMP-regulated substances at covered processes are being monitored continually so that potential exposure to chemical substances can be measured during and following a natural disaster.
While EPA is not requiring implementation of standby or emergency power for the entirety of an RMP process, EPA is proposing to require air pollution control or monitoring equipment associated with prevention and detection of accidental releases from RMP-regulated processes have standby or backup power to ensure compliance with the intent of the rule.
EPA is soliciting comments on the proposed amendments and has posed questions regarding them.
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