EPA is proposing to require all facilities with Program 2 and 3 processes to conduct a root cause analysis as part of an incident investigation for an RMP-reportable accident as defined under 40 CFR 68.42. This includes requiring the root cause analysis to include specific elements, requiring the use of a recognized investigation method, and requiring that investigations are completed within 12 months. Based on RMP-reportable accidents from 2016 to 2020, EPA estimates this provision will apply to an average of 100 facilities per year.
In the 2017 amendments rule, EPA amended 40 CFR 68.81 to add that incident investigations shall include “the factors that contributed to the incident including the initiating event, direct and indirect contributing factors, and root causes” and that “root causes shall be determined by conducting an analysis for each incident using a recognized method.” In the 2019 reconsideration rule, EPA rescinded the root cause analysis requirements, stating that EPA was “unable to make a direct connection between the presence or absence of these provisions and a number of accidents prevented” (84 FR 69834). EPA also stated that it did not rely exclusively on a comparison of costs and benefits to justify the rescission but also acted to maintain consistency with the OSHA PSM standard. As a result of the 2019 removal of root cause analysis requirements, EPA’s current causal incident investigation requirements under 40 CFR 68.60 and 68.81 require investigation into only “the factors that contributed to the incident.”
Since the 2019 reconsideration rule, EPA has coordinated with OSHA to ensure that any proposed incident investigation root cause analysis provisions do not contradict OSHA PSM requirements. In the 2019 reconsideration rule, EPA also indicated that it had not conducted any overall analysis of data from RMP accident investigations conducted by regulated facilities to determine how well these investigations identified causes and contributing factors (84 FR 69834). However, this is in part because EPA has not required the investigation of root causes and therefore cannot analyze such data. EPA therefore revisited commenters’ points concerning facilities with more than one accident. Updated analysis of EPA’s RMP accident reporting data identified repeated accidents in facilities within the same process.
For the 2019 reconsideration rule, EPA relied upon data demonstrating that only a subset of facilities experience accidents. This holds true for the updated analysis, with only 3 percent (n = 382) of facilities between 2016 and 2020 reporting one RMP-reportable accident and 0.5 percent (n = 70) of all RMP facilities reporting two or more RMP-reportable accidents during that period. Among facilities reporting accidents, facilities who reported one often have multiple accidents, indicating a failure to properly address circumstances leading to subsequent accidents. For example, between 2016 and 2020, these facilities accounted for 36 percent (n = 176) of all accidents reported (n = 488). Additionally, of these 70 facilities, 61 percent (n = 43) had experienced another accident prior to 2016. Between 2004 and 2020, 18 facilities had more than 10 accidents each, with two facilities reporting over 20 incidents each to EPA.147 These accidents may have been preventable if root cause analyses had been required. EPA believes multiple accidents result partly from a failure to thoroughly investigate and learn from prior accidents.
Although EPA cannot be certain that in all cases, subsequent accidents are due to a failure to conduct a root cause analysis of an earlier incident, EPA finds that of the 70 facilities with multiple accidents between 2016 and 2020, 60 percent (n = 42) reported repeat causal factors within the same process. While this could be a failure to implement incident investigation findings or could be unrelated to the earlier incident, multiple accidents within the same process with the same causal factors indicate a likely failure to rectify prior failures and root causes of these incidents. EPA believes the occurrence of such subsequent incidents indicates an overall failure to identify and implement controls that may have prevented future incidents.
In proposing to reestablish the root-cause analysis requirements, EPA has determined that there are likely no legitimate reliance interests associated with the 2019 reconsideration rule’s elimination of these requirements. The 2019 rule has only been in place for three years and any accident investigation in the past, under way, or that otherwise would be required that predate the proposed rule will not have to be revised or changed in scope should EPA finalize the proposed change. Further, the burden of the proposed root cause analysis is relatively small. Few sources will have to conduct one because accidents occur at a small number of sources and many sources perform root cause analyses already in a manner consistent with industry or company protocols.
The potential benefit from improved incident investigations is apparent from the significant percentage of sources and processes that have another accident after the first. Rather than relying on negotiations in enforcement actions as a basis for promoting root cause analyses as necessary under the approach of the 2019 reconsideration rule, EPA believes the delays of negotiations and the transaction costs of such an approach, and the benefit of a root cause approach to incident investigations makes it more prudent and reasonable to impose a rule requirement for root cause analysis in incident investigations rather than the approach adopted in 2019.
Root Cause Analysis Background
EPA discussed root cause analysis at length in the 2016 proposed amendments. As discussed, CCPS defines root cause analysis as: “A formal investigation method that attempts to identify and address the management system failures that led to an incident. These root causes often are the causes, or potential causes, of other seemingly unrelated incidents. Root cause analysis identifies the underlying reasons the event was allowed to occur so that workable corrective actions can be implemented to help prevent recurrence of the event (or occurrence of similar events).” EPA also discussed that causes of incidents are commonly referred to as “causal factors” (also known as contributing causes, contributory causes, contributing factors, or critical factors). CCPS defines a causal factor as a “major unplanned, unintended contributor to an incident (a negative event or undesirable condition), that if eliminated would have either prevented the occurrence of the incident or reduced its severity or frequency.” Causal or contributing factors usually have underlying reasons for why they occurred, which are known as “root causes.” CCPS defines a root cause as a “fundamental, underlying, system-related reason why an incident occurred that identifies a correctable failure(s) in management systems.” EPA proposed that root causes shall be determined by conducting a root cause analysis for each incident using a recognized method or approach. CCPS’ “Guidelines for Investigating Chemical Process Incidents” discusses incident investigation approaches and techniques and root cause analysis methods.
EPA previously discussed that identifying and addressing incident contributing factors and their root causes helps eliminate or substantially reduce the risk of reoccurrence of the incident and other similar incidents, citing notable incidents that CSB investigated. These CSB investigations of the 2004 Formosa Plastics Corporation incident, the 2005 BP Texas City Refinery incidents, and the 2010 Millard Refrigerated Services incident found that root causes of prior, similar incidents were not identified, a lack that contributed to subsequent incidents.
In the 2016 proposed amendments, EPA also discussed that root cause analysis of accidents is an accepted safe management practice used by many industries, noting that the American Chemistry Council (ACC) conducts root cause analyses as part of its Responsible Care program. In addition, New Jersey’s TCPA, as well as California’s PSM for Refineries, Contra Costa County Health Services,159 and the City of Richmond, California, Industrial Safety Ordinances, already require root cause analyses for major chemical accidents.