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  • How do the different parts of particulate matter (PM) fit together?

    The various parts of PM in the NEI are related as follows. PM10-FIL > PM25-FIL because PM10-FIL includes PM25-FIL PM25-PRI = PM25-FIL + PM-CON This equation only applies at the process level. Because some sources only can report PM2.5 (due to test method differences), this equation does not apply to…

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  • How does PM2.5 relate to PM species such as EC, OC, SO4, NO3, PMFINE, and DIESEL-PM25?

    Primary PM2.5 estimates are speciated into the five PM species in the NEI: elemental (black) carbon (EC), organic carbon (OC), nitrate (NO3), sulfate (SO4), and the remainder of PM25-PRI (PMFINE). Diesel engine PM25-PRI and PM10 emissions are also labeled as DIESEL-PM25 and DIESEL-PM10 for mobile source diesel engines. For all…

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  • Accidental releases from non-covered processes

    Should the owner or operator include accidental releases from processes containing listed substances below the threshold quantity in the five-year accident history required under the hazard assessment provisions of 40 CFR Part 68, Subpart B, and in the incident investigation requirements under 40 CFR Part 68, Subparts C and D…

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  • Do I have to report accidents that resulted in medical treatment?

    I had a release where several people were treated at the hospital and released; they attributed their symptoms to exposure. We do not believe that their symptoms were in fact the result of exposure to the released substance. Do we have to report these as offsite impacts? Yes, you should…

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  • What sources make up the Tier 1 categories used in the emissions trends?

    Tier 1 categories are assigned by source classification codes (SCCs) that are the most specific processes available in the NEI. The latest SCC list with the Tier 1 assignments can be downloaded from the EPA SCC website in Comma Separate Values (CSV) format.

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  • What is the cause of the large decrease in electric utility emissions, particularly sulfur dioxide, starting in 1995?

    SO2 emissions reductions from utilities during this time are primarily attributed to the impacts of the acid rain program. As described on EPA’s Acid Rain Program web page, Phase 1 of this program began in 1995 and affected 263 units at 110 most coal-burning electric utility plants in 21 eastern…

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  • What is the definition of "offsite property damage?"

    I am working on the five-year accident history portion of the hazard assessment under the RMP. Section 68.42(a) tells me to include "all accidental releases from covered processes that resulted in deaths, injuries, or significant property damage on site, or known offsite deaths, injuries, evacuations, sheltering in place, property damage…

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  • When does the accident history's five-year period begin?

    The hazard assessment requirements under 40 CFR Part 68, Subpart B include provision of a five-year accident history, as specified at §68.42. When does the five-year period to be reported in the accident history begin? The five-year accident history must include information on all accidental releases from covered processes meeting…

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  • What is the definition of injury?

    Under the hazard assessment requirements of 40 CFR Part 68, Subpart B, an owner or operator must document a five-year accident history including all accidental releases from covered processes that resulted in deaths, injuries, or significant property damage on site, or known offsite deaths, injuries, evacuations, sheltering in place, property…

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  • Do Program Level 1 processes need to do five-year accident histories?

    What is the relationship between the accident history criteria for Program 1 and the five-year accident history? If my process is eligible for Program 1, do I still need to do a five-year accident history? The five-year accident history is an information collection requirement that is designed to provide data…

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  • What is included in the emissions “Tiers”?

    The Tiers are assigned by a Source Classification Code (SCC), which has the most detail about the emissions processes that generate the emissions. The full list of SCCs, their associated Tiers, and the SCC descriptions is available online at https://ofmpub.epa.gov/sccwebservices/sccsearch/ .

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  • Five-Year Accident History for Non-Gas Releases

    Pursuant to 40 CFR §68.42(a), the owner or operator of a stationary source subject to the risk management program regulations must document significant accidental releases of regulated substances from a covered process in the five years prior to the submission of an initial or updated risk management plan (RMP). For…

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  • What level of off-site property damage triggers five-year accident history reporting?

    What level of off-site property damage triggers reporting? Any level of known offsite property damage triggers inclusion of the accident in the five-year accident history. You are not required to conduct a survey to determine if such damage occurred, but if you know, or could reasonably be expected to know…

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  • Do I need to report releases for processes that have shut down?

    A process involving a regulated substance had an accidental release with off-site consequences two years ago. The process has been shut down. Do I have to report anyway? No. The release does not have to be reported in your accident history. Your Risk Management Plan only needs to address operating…

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  • Are releases under prior ownership included in the five-year accident history?

    Documentation of a five-year accident history is required as part of the hazard assessment under 40 CFR Section 68.42. Should a stationary source subject to the risk management program regulations report as part of the five-year accident history any accidents that occurred when the facility was under prior ownership? Yes…

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