• After Pan American merged with Standard Oil of Indiana, ownership passed to Amoco.[2] This is worded a bit confusingly, maybe go with "Pan American merged with Standard Oil of Indiana in 1954 to form Amoco" or something similar.
  •  Done. Added new inline citation to fully support this statement, as it was not 100% clear from the previous source.
• but BP were extremely successful in turning the tide shouldn't this be "BP was"?
  •  Done.
• At the time of the merger, the plant was losing money given that the previous paragraph mentions multiple mergers, maybe do "At the time of the 1999 merger"
  •  Done.

• It emerged after the accident that the plant had been poorly maintained for several years.[10] given what else is written in this section, it seems like this was known at the time as well.
  •  Done. The idea is that poor plant conditions were made public after the accident, although they were known inside BP well before it. For clarity, I changed to the simpler The plant had been poorly maintained for several years.
• I'd spend a paragraph or two going over past incidents in more detail than is done here. Another on the cutbacks on spending and their results. Then maybe two more on audits. Currently there's way too many small paragraphs and this section feels disjointed (for a start, merge paragraphs 3 and 4).
  • I have merged paragraphs 3 and 4. Also, the section now starts with past accidents, then shifts to maintenance expenditure cuts and finally touches on the audits.
  • Regarding previous accidents, I have added a significant event occurred in 1979 and expanded on the 23 fatalities occurred.
  • There is now only one paragraph aggregating all audits, plus a final paragraph on the diffusion the audit results among BP higher management.

• Disposal of hydrocarbon vapors and small amounts of associated liquids from vent and relief during plant upsets or planned shutdowns was to vessel F-20, a blowdown stack. would reword -- maybe like "Excess hydrocarbon vapors and liquids were sent to vessel F-20, a blowdown stack."
  • Changed it to Excess hydrocarbon vapors and liquids from vent and relief were sent to vessel F-20, a blowdown stack. I think it is important to leave the "vent and relief" to give context (for example, drained liquids did not go to the blowdown stack).

• Construction, turnaround, and routine activities at the refinery often required the installation of trailers and portable buildings for use as offices, workshops, etc. for the use of employees and contract workers. would go with something more like "Portable buildings and trailers were often installed for use as offices during construction and maintenance."
  •  Done.
• established the agreed layout of trailers "agreed" with who?
  • Basically "internally agreed", as in, among different departments and vouchsafed by risk assessment. I have changed it to established an acceptable layout of trailers, I hope it is more clear.
• actions arising from the double-wide trailer MOC were still open clarify what this means?
  • I have changed it to recommendations issued in the analysis of the change involving the placement of the double-wide trailer were still open. I hope this clarifies.

• With the first paragraph... is this general procedural info? If so, probably belongs somewhere else, and if not, probably should include details on when this was happening.
  • It is procedural. The pre-start-up safety review should have happened before the start-up commenced, but it did not. This is one of the findings of the investigations and as such has been highlighted also somewhere else in the article. I have therefore shortened the text and included it at the beginning of the following section /* Early Morning */ :Because plant start-ups are especially prone to unexpected situations, operational practice requires the application of a controlled and approved pre-start-up safety review (PSSR) procedure. BP had one, but it was not adopted in this case.
• Second paragraph also seems kinda out of place.
  • It contained information that, having transpired after the investigations, is repeated elsewhere in the article. Indeed, I think the paragraph was redundant, so I deleted it.

• this transmitter, which was relied upon during the whole start-up operation, was not calibrated and its readings were not reliable this is talking about the indicator that would be read to see if it's 99%, right? should be clarified.
  • It is indeed that transmitter. I have reworded The process control level transmitter was designed to indicate the raffinate level within a 5-foot (1.5 m) span from the bottom of the splitter tower to a 9-foot (2.7 m) level. A high-level alarm dependent on this transmitter sounded as intended when a level of 7.6 feet (2.3 m) from the bottom was reached. However, during start-up it was common to ignore this alarm and fill up to a level of 99% (as indicated by the transmitter) to prevent damage to the furnace heating the splitter bottom. Unbeknown to the operators, the process control level transmitter, which was used to monitor the level in the splitter during the whole start-up operation, was not calibrated and its readings were not reliable.
• An independent level alarm triggered by a high-level switch should also have sounded at 7.9 feet (2.4 m) but failed to. is there a reason why this failed?
  • The proximate cause is unknown (I have just double-checked the investigation report to make sure I had not missed any info here). Instrument failures do happen and should be prevented or timely diagnosed by periodic maintenance/inspection/function test/calibration. These were not carried out, which is the real problem in the context of this accident and the widespread lack of safety oversight at the refinery. Lack of maintenance oversight on safety critical systems is highlighted elsewhere in the article (investigation reports and lessons learned in process safety).
• When did the start-up process start and when was the alarm sounded and ignored? Would be nice to know if this happened before or after 5am.
  • At 3:09 am. I have added it in the text (and cited the page in the CSB report that supports this).
• One of the two day-shift supervisors ("A") arrived late for work at the central control room and did not have a handover with the night shift. when were they supposed to arrive and when did they arrive?
  • Changed to At 7:15 am, more than one our late on the commencement of his shift (6:00 am), one of the two day-shift supervisors ("A") arrived at the central control room. Because of his lateness, he could not go through the required handover with the night shift.
• (Immediately after the BP-Amoco merger, the decision was taken to eliminate a second board operator position). this might be better to include as a footnote.
  •  Done (although slightly changed to The need for two operators, especially for dealing with potential plant upsets, had been highlighted in several reports since before the Amoco–BP merger., a bit more nuanced and consistent with the source supporting the statement).

• Maybe rephrase The required temperature for the tower reboiler return flow was 135 °C (275 °F) at 10 °C (18 °F) per hour but the procedure was not followed. During this start-up, this return flow temperature reached 153 °C (307 °F) with a rate increase of 23 °C (41 °F) per hour. slightly: The required temperature for the tower reboiler return flow was 135 °C (275 °F) with a rate increase of 10 °C (18 °F) per hour, but this procedure was not followed: during start-up, the return flow temperature reached 153 °C (307 °F) at a rate of 23 °C (41 °F) per hour.
  •  Done
• The erroneous 93% reading from the defective level transmitter the article only previously mentions the reading was "less than 100%", so this phrasing is a bit confusing. Also I'm maybe just missing something but if 93% would only be ~9 feet, then wouldn't 67 feet be way over 100%? The details of how this reading works could be clarified.
  • The level transmitter, by definition, could only read up to 100% of its range, which was from 5 feet (0%) to 9 feet (100%), as stated in the /* Early morning */ section. Anything above 9 feet would have read as 100% (i.e. 9 feet), regardless of how much liquid there actually was in the column (basically, under no circumstances should the liquid have been above the 9 feet mark; that is why by design there was no way of measuring levels above 9 feet: should you be above 9 feet, just make sure to empty the tower until you are safely below 9 feet). However, as stated in the /* Early morning */ section, this transmitter had not been calibrated and its readings were not reliable; this is why it never reached 100%. Because of this, and the concurrent failure of the redundant level switch (which should have sounded an alarm at 99% of the same 9 feet range), the operator thought there was liquid only at the bottom of the column, while in fact the whole column was becoming flooded. I have changed the wording as follows: The defective level transmitter still erroneously indicated an ongoing safe level condition in the tower. However, there was still no flow of heavy raffinate from the splitter tower to the storage tank as the level control valve remained closed; instead of the hydrocarbon liquid level being at 8.65 feet (2.64 m), i.e. 93% of the instrument range, as indicated, it had actually reached 67 feet (20 m). I hope it is clearer.

• Meanwhile, at 12:00 pm contractors had left the trailers for a lunch organized to celebrate one month without lost-time injury. They were back by 1:00 pm.[52] this is ironic/amusing but not sure it's relevant in this location. Might be better somewhere else? Maybe in the second-to-last paragraph of this section.
  •  DoneI have moved it to an explanatory footnote appended towards the end of this section.
• level control valve was finally opened why?
  • The CSB report is not conclusive not very clear on this. The operator was under the impression that there was in fact flow out of the tower, because the flow transmitter was giving him a reading of about 4300 bpd. In other words, he thought the level control valve was open, although at a low opening range of perhaps a few percent of its capacity, when in fact it was fully closed and the actual flowrate was 0 bpd. This is mentioned in the /* Early morning */ section. My interpretation is that at some point before 12:42 the operator must have thought that the outflow had to be increased from what he thought was about 4300 bpd to a higher output, perhaps because he was seeing the level increasing from, say 93% to close to 99% (although obviously we know that the level transmitter data were completely wrong; but the operator believed them). Bear in mind that this is my interpretation, likely to be correct but not actually spelled out in the investigation report. Because of this, I am reluctant to change the text because it would basically amount to original research.
• by the subsequent fire that followed the violent explosion "subsequent" is redundant here.
  •  Done, deleted "subsequent".

• Maybe worth mentioning the primary fire department that responded here?
  • From all the sources I have found, it was a mutual aid service set up by the chemical and refining plants of Texas City. I have spelled out the name of this mutual aid (IMAS) in the text now.

• Mogford report looks good.
  • Noted
• Guessing the Stanley report wasn't available publicly? If so the section looks fine.
  • Indeed I could not find it anywhere... but now I accidentally stumbled upon a copy! See here: https://web.archive.org/web/20081207143706/http://images.chron.com/content/chronicle/special/05/blast/stanleyreport.pdf. I have added a citation to this document. I have also reviewed it and expanded (although not extensively) the Stanley report section.
• "BP Group" is inconsistently capitalized.
  •  Done
• of the date of publication of the report none had actually been sacked. any updates on this?
  • None that I can find, except for Parus (for whom see explanatory note appended to the sentence you quote). However, I think the main point here is to highlight that two years after the facts BP had not yet taken action against these high profile executives. I think the sentence can stand as it is.
• The director of the Cherry Point refinery was promoted to oversee better implementation of process safety at BP. has a cn tag and no source.
  • Yes, that statement predates my article re-hauling. I cannot find a source for this. Since this statement reflects an action taken by BP after the report was issued, and not any content of the Baker report itself, I have deleted the statement altogether.
• Maybe better to summarize Merritt's quote? That's quite long.
  •  Done
• Process Safety Management or PSM using a parenthetical here would be consistent with the rest of the article
  •  Done
• the Contra Costa County, California own local regulator this isn't clear/proper grammar
  • Changed to Contra Costa County, California hazardous materials programs (see www.cchealth.org/health-and-safety-information/hazardous-materials). I believe "<county>, <state> <thing>" is correct grammar to indicate a thing from a certain county in a certain state, or am I wrong?

• Paragraphs 2-4 here should probably be in their own subsection (para 1 appears to be mostly summarizing the settlements, prosecution, and fines, while 2-4 aren't really summarizing anything else).
  •  Done Paragraphs 2-4 are now in own subsection titles "BP's response and fate of the refinery"
• In other congressional hearings dedicated to subsequent BP accidents in the U.S., the Texas City case history was consistently presented within the pattern of degraded safety culture at BP. a secondary source would be ideal for this but not necessary.
  • It is a fair point, but I cannot find a source that lists all the hearings in one place. I would be inclined to leave this untouched.
• The Eva Rowe section could be written a bit clearer ("she let it be known" isn't great wording), and also a source other than from a law firm for the settlement would be good.
  •  Done ("she said" and source from Houston Chronicle used).
• By August 2008 only one of the approximately 4,000 claims remained open. presumably this was eventually settled, right?
  • I am sure it was, because not settling would have meant a criminal trial, of which there was none (this is not about the public criminal prosecution for violation of the Clean Air Act). However, I really cannot find sources about this last settlement. I will leave the sentence as is for the moment, but if you have any suggestions to improve it please let me know.

• stepped up their game is not really encyclopedic tone
  •  Done Changed to took action

• Looks good.
  • Noted.

• Deepwater Horizon oil spill is already linked in the article.
  • Deleted. Added two links to other U.S. refinery fires instead.

Noting that while I did spot-check a few references, I did not do an in-depth source check as this article is quite long. A few general notes:

• It's not great to have >3 citations for a statement unless necessary. Being more specific about what supports what makes verification easier.
  • There are XYZ such instances
    • One at the end of the second paragraph of /* Investigation reports */. Here one reference is to a secondary source, the rest are just callbacks to the investigation reports in their entirety. The citations of the investigations reports here is probably redundant so I have deleted them. Only one citation is left.
    • At the end of the first paragraph of section /* CSB report */. Yes, too many, I have deleted one.
    • In the last paragraph of the new section /* BP's response and fate of the refinery */. This is just citations to the reports individual of the congressional hearings mentioned in the sentence to which the citation is appended In other congressional hearings dedicated to subsequent BP accidents in the U.S., the Texas City case history was consistently presented within the pattern of degraded safety culture at BP. This sentence is the subject of one of your comments above. I did try to find a secondary source here but could not, so I think having citations of the primary sources to which the sentence alludes is the lesser evil.
    • At the end of the first paragraph of section /* Impact on process safety */: The disaster had a notable impact in the domain of process safety. Texas City has become a classic case history used to explain failings in both management and technical barriers in process plants. These citations are to book chapters where Texas City is presented as a case history. I think having several citations here is useful, because they do not just support the statement they are appended to, but give a callback to important process safety books where Texas City is discussed in specific chapters or sections.
• Generally preferable to keep things in order (e.g. [1][2][3], not [2][1][3]).
  • I think I have read in a help page (obviously I can't find it now...) that this is not really necessary. Additionally, using (mostly) the visual editor like I do does not allow for this as the numbering changes between the visual editing interface and the "final product". However, I think I have managed to do it now, have a look at last version.
• The citation style isn't totally consistent here but that isn't a requirement for GA.
  • Noted. Actually I typically strive to have a consistent style. For my own education, what inconsistencies have you spotted?

• Maybe also mention cost of settlements?
  •  Done
• Should probably say "relief valve" instead of "overpressure protection".
  •  Done
• Would suggest summarizing the "Aftermath" and "Impact on process safety sections" outside of just the first paragraph.
  •  Done Added one more paragraph: The accident had widespread consequences on both the company and the industry as a whole. The explosion was the first in a series of accidents (which culminated in the Deepwater Horizon oil spill) that seriously tarnished BP's reputation, especially in the U.S. The refinery was eventually sold as a result, together with other North American assets. In the meantime, the industry took action both through the issuance of new or updated standards and more radical regulatory oversight of refinery activities. I hope this is good.

• Suggest linking the CEO names in the collage image.
  •  Done
• Licenses look good.
  • Noted