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Shillington, PA, United States

Patschke C.,ABSG Consulting
Process Safety Progress | Year: 2011

The OSHA Refinery National Emphasis Program (RNEP) and OSHA Voluntary Protection Program incorporate specific questions relative to many recognized and generally accepted good engineering practices (RAGAGEP). Many of the same RAGAGEP can be expected to be used in the OSHA Chemicals NEP as well. To comply with OSHA's process safety management (PSM) regulation and improve process safety at their sites, chemical industry personnel should be aware of what RAGAGEP OSHA is recognizing and inspecting against and their key requirements. This article will discuss: (1) OSHA's expectations for compliance with RAGAGEP, including some of the RAGAGEP OSHA references in compliance directives, instructions, and citations, (2) some citations issued by OSHA involving RAGAGEP, and (3) common RAGAGEP compliance issues ABSG Consulting observes when conducting PSM audits and assessments throughout the petrochemical and related industries. © 2011 American Institute of Chemical Engineers. Source

Lin J.C.,ABSG Consulting
PSAM 2014 - Probabilistic Safety Assessment and Management | Year: 2014

Due to the flammability and explosion characteristics of the propane vapor cloud, a nearby propane tank farm could possibly present a significant risk to the operation of nuclear power plants. Accidental releases of propane may occur in the propane supply pipeline, at the propane storage tanks, or on the propane transportation routes due to propane transport trailer truck accidents. Loss of containment could result in toxic vapor cloud affecting the nearby nuclear plant control room habitability, Vapor Cloud Explosion (VCE) overpressure due to both deflagration and detonation, Boiling Liquid Expanding Vapor Explosion (BLEVE) missile impacts, and thermal radiation from BLEVE fireballs, flash fires, pool fires, and jet fires. The thermal radiation impact ranges of a pool fire, jet fire, flash fire, and BLEVE fireball is typically less than the shortest distance between the propane tank farm and the nearby nuclear plant. The explosion overpressure and missiles are the most critical hazards to the nearby nuclear plants. Only VCE overpressure greater than 1 psi and BLEVE missiles can potentially impact the PRA related structures and equipment at the nearby nuclear plant. The total frequency of unacceptable damage at the nearby nuclear plant resulting from accidents at the propane tank farm and from propane transport truck accidents is estimated to be less than 10-7 per year. This paper discusses the insights gained from the analysis of the risk impact on a nearby nuclear plant due to accidental release of propane from the propane terminal related operations, including the propane storage/distribution facility and the propane transport trucks. The important considerations used in the analysis of the risk scenarios resulting from a propane transport truck accident, large and small releases at the propane distribution facility, and exploding missile hazards are presented. Source

Lin J.C.,ABSG Consulting
International Topical Meeting on Probabilistic Safety Assessment and Analysis 2013, PSA 2013 | Year: 2013

The risk of spent fuel pool (SFP) fire that may result from SFP leaks or other loss of inventory events is evaluated. The frequency of uncovery of spent fuel is estimated as a surrogate for the risk of spent fuel fire. The analysis includes both internal and external initiating events that may occur during power operation and during outage. The four categories of initiating events considered are: loss of SFP cooling, loss of SFP inventory, loss of offsite power, events that may cause catastrophic failure of the SFP structure, including earthquakes, tornado-generated missiles, aircraft crashes, and heavy load drops. The possible evolutions involved in the process from shutdown, reactor disassembly, fuel movement, to reactor reassembly are grouped into three general configurations: SFP to transfer canal gate installed, SFP to transfer canal gate removed and fuel transfer tube (FTT) isolation valve closed, and SFP to transfer canal gate removed and FTT isolation valve open. The dominant contributor to the frequency of uncovery of spent fuel stored in the SFP is seismic events. Power operation has the highest frequency of spent fuel uncovery among the different plant configurations because it has the longest duration compared to the outage configurations. Among the three outage configurations, the two configurations with the SFP gate installed or FTT isolated have greater contributions to the frequency of spent fuel uncovery, also because of the longer duration compared to the outage configuration in which the FTT is open. Source

Lin J.C.,ABSG Consulting
10th International Conference on Probabilistic Safety Assessment and Management 2010, PSAM 2010 | Year: 2010

The risks from lightning events at LNG facilities may arise from potential arcing or burnthrough of the pressure boundary for the hydrocarbon containment and the subsequent ignition that may result from the lightning attachment. The critical targets for lightning attachment and lightning strike-induced burnthrough or arcing include the exposed containing equipment (e.g., pipes, valves, pumps, vaporizers, tanks/vessels, etc.) of hydrocarbon products (LNG/NG). The greatest risk of release of LNG/NG at LNG terminals during the lightning events is likely from the burnthrough effect associated with direct strikes to the LNG/NG containing pipes, since such other equipment as tanks/vessels, valves, etc. is designed with greater wall thickness. Because of the grounding system design, sideflash due to potential difference is unlikely. Only pipes with a wall thickness less than 4 mm can be punctured by the lightning burnthrough effect. At some LNG terminals, only LNG/NG pipes with a diameter of 8'' or less are susceptible to lightning burnthrough puncture. Because of the piping service class design, most of the high pressure LNG and NG pipe segments are not susceptible to lightning puncture. The hole size that may be produced by the lightning direct-strike burnthrough is usually all less than 9 mm, based on a very conservative charge transfer of 350 coulombs. The largest hole sizes may result from the smaller LNG/NG pipes. Source

Lin J.C.,ABSG Consulting
PSAM 2014 - Probabilistic Safety Assessment and Management | Year: 2014

Because the probable maximum events selected in FSAR for nuclear plants may not be the maximum possible events, they could possibly be exceeded by more severe events in the future. As such, there is a need to re-evaluate the other external hazards, especially those associated with the natural phenomena. To ensure that the maximum possible intensities of the natural phenomenon hazards are identified and analyzed, one has to be able to identify the physical limits of the parameters that define the intensities of the hazards. However, in some cases, it is truly difficult to identify the absolute, physical limits of parameters associated with selected natural hazards. One way to address the issue of exceeding the probable maximum event is to evaluate the quantitative risk in terms of core damage and large early release frequencies resulting from the specific hazard of concern. This will require the estimation of the hazard frequency. While it may be possible to assess the occurrence frequencies of selected natural phenomena of limited intensity, the uncertainty in the assessed frequencies of events with magnitude beyond the range of historical occurrences may be uncomfortably high. Furthermore, some of the external hazards may not lend themselves to an easy assessment of their occurrence frequencies. As such, deterministic criteria will still need to be used for the risk evaluation of selected hazard events. This paper groups the entire set of other external hazards into a number of categories and discusses the characteristics, PRA evaluation methods, and other aspects of each of these groups. Source

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