Talk:Collapse of the World Trade Center

Timestamps

The structural failure first being observed at the last second of 09:58 does not mean it was first observed at 09:59. NIST also didn't explicitly state that they rounded off the 09:58:59 collapse initiation; 09:59 could very well be a reference to everything that came immediately after (i.e., if it commenced at 09:58:59, it would still have been collapsing at 09:59; doesn't change the fact that the process kicked off while it was still 09:58).

Similarly, the 9/11 Commission indicated that 17 minutes passed between the two impacts, despite reporting 08:46:40 and 09:03:11 for each one (16 minutes and 31 seconds; quite a way off from 17), and claimed the towers burned for 102 and 56 minutes before collapsing, even though the precise timestamps they gave (08:46:40–10:28:25 and 09:03:11–09:58:59) say otherwise.

One of the fundamental principles of Wikipedia is that "all articles must strive for verifiable accuracy, citing reliable, authoritative sources, especially when the topic is controversial." It goes without saying that the September 11 attacks remain a highly sensitive topic 22 years later. Both agencies made it a point to state that the South Tower did not begin collapsing at 09:59; it commenced while it was still 09:58, regardless of any colloquial language used later on. Intentionally misrepresenting numbers out of convenience is, by definition, inaccurate, and the footnotes in the article were created to dispel certain misconceptions about the times at which certain events happened. Hmm1994 (talk) 22:21, 12 September 2023 (UTC)

First of all, assume good faith. Claiming other editors are [i]ntentionally misrepresenting numbers is not a great way to start your argument.

We also need to maintain readability. That means rounding the numbers can sometimes be beneficial for our readers, especially since the exact times are already cited for them to inspect when they want precision. — The Hand That Feeds You:^Bite 22:33, 12 September 2023 (UTC)

I do know it's a good faith edit, but I consider it as an intentional misrepresentation of the South Tower's moment of collapse initiation not carried out for any underhanded reasons, just simply because people feel 09:58:59 is a mouthful (and, yes, that's a sentiment I can get behind). My suggestion was not that it be changed to "09:58:59", "the last second of 09:58" or "one second before 09:59". Rather, that the time be changed back to 09:58, because that's just as easily read and it was the minute in which the collapse verifiably began; the footnote serves to clarify that it continued into 09:59. Hmm1994 (talk) 23:29, 12 September 2023 (UTC)

Also, NIST's official website states that the South Tower was hit at 9:02 and collapsed at 9:58, so the 9:59 wasn't a round up from 9:58:59; it was when almost all of the death and destruction would've occurred. I'm not sure the impact time should be changed since there is a lot of disagreement over what time the South Tower was hit at, but we have two government sources saying the collapse began at 9:58, neither of which rounded the collapse initiation to 9:59. Hmm1994 (talk) 09:47, 18 September 2023 (UTC)

The exact times are disputed. See explanatory notes d, e, f, g, and h. -Jordgette [talk] 15:58, 18 September 2023 (UTC)

The exact time of the South Tower's collapse initiation is not disputed per explanatory note h: "NIST and the 9/11 Commission both state that the collapse initiated at 9:58:59 a.m., which is rounded to 9:59 for simplicity." NIST never claimed that they rounded the tower's collapse initiation time to 9:59; the 9:59 is in reference to the fact that the tower was still collapsing at 9:59. To the contrary, they logged the collapse initiation as having taken place at 9:58. Hmm1994 (talk) 16:32, 18 September 2023 (UTC)

When they say 102, 56, or 17 minutes they're just rounding to the nearest whole minute. The exact durations from the timestamps in minutes are 101:45, 55:48, and 16:31. The rounded figures are fine. MiguelMunoz (talk) 00:44, 26 November 2023 (UTC)

References

Is BLAZE-SHIELD D necessary?

Is this paragraph about the specific fire-proofing necessary?

According to NIST NCSTAR report, in 1969, BLAZE-SHIELD D fireproofing was used, a mixture of cement and asbestos fibers. When its use was discontinued, the spraying proceeded with one of three different sprayed fire-resistive material (SFRM) insulation: BLAZE-SHIELD DC/F, BLAZE-SHIELD II, or vermiculite plaster, which was coated on the trusses, perimeter columns, spandrels, and one or more surfaces of the core columns.

I would like to just remove it. Thomas B (talk) 20:13, 7 November 2023 (UTC)

I don't think that the brand name is needed either, but the composition is important in view of the health issues faced by survivors and workers.Acroterion (talk) 23:37, 7 November 2023 (UTC)

Good point. The article already mentions asbestos and I'll reduce the rest to "vermiculite plaster". Thomas B (talk) 07:05, 8 November 2023 (UTC)

Depending on the source of vermiculite, that could contain asbestos too, albeit inadvertently. However, I haven't seen any sources that characterize the vermiculite additive, so that wording should be fine. Acroterion (talk) 12:15, 8 November 2023 (UTC)

Evactuation Questions

When was WT7 evacuated? I assume that the two big towers were evacuated immediately after impact. I'm not sure if they evacuated both towers after the first impact, or if the evacuation of the south tower didn't begin until it was hit. But I have no idea at all about WT7, since it wasn't hit. Did they evacuate it immediately on impact? Or did the evacuation begin when it got hit with the debris that started the fires? The article is silent on this question. The section on the collapse of WT7 says that "Some firefighters entered 7 World Trade Center to search the building." It says nothing about anybody else that may have been there. It also says that "…the sprinkler system required manual initiation of the electrical fire pumps." This information would be more useful if I knew if there were still people there to do this. And did the fire fighters turn those pumps on? Also, the article has a section called "Emergency response and evacuation," but it never discusses evacuation. I would like to see answers to these questions in the article. MiguelMunoz (talk) 00:15, 26 November 2023 (UTC)

Time to collapse explanation

The fact that the South Tower was hit lower does NOT mean there was double the pressure on the columns. You can verify this by comparing the strains in NCSTAR 1-6D fug 4-72 with 121 Abdullah Ali 4z5 (talk) 02:31, 27 November 2023 (UTC)

Comparing the numbers ourselves is original research, which is not allowed on Wikipedia. You'd need a reliable, secondary source making the claim. — The Hand That Feeds You:^Bite 13:02, 27 November 2023 (UTC)

The at least let's leave the dubious tag up. Abdullah Ali 4z5 (talk) 13:18, 27 November 2023 (UTC)

I don't see any reason to. — The Hand That Feeds You:^Bite 13:50, 27 November 2023 (UTC)

I agree that we should remove the dubious tag. But also change "double" to simply "more". The source (NYT) reads "Ultimately, it was the combination of structural damage and the fires, fueled by thousands of gallons of jet fuel, that brought the buildings down. The south tower was also hit at a lower point, meaning there was more weight bearing down on the damaged floors." Thomas B (talk) 13:56, 27 November 2023 (UTC)

I'd be fine with that change.

Abdullah Ali 4z5, I reverted your most recent change for several reasons:

1. Changing "46 minutes later" to "70% longer" is not helpful for the average reader.

2. The changes read more like a school essay than an encyclopedic entry

3. Removing the NYT article in favor of the NIST report, when we generally prefer secondary sources.

I think Thomas B's suggestion is the better solution. — The Hand That Feeds You:^Bite 15:38, 27 November 2023 (UTC)

It's not good having such a blatant falsehood there. Abdullah Ali 4z5 (talk) 15:58, 27 November 2023 (UTC)

I have implemented the change ("double" -> "more") and removed the dubious tag (since that doesn't seem doubtful, based on the source). What blatant falsehood remains? Thomas B (talk) 16:45, 27 November 2023 (UTC)

It's a blatant falsehood that the greater weight above impact contributed to the collaose. That is because the size of the columns also scales with their load. Indeed, because of this, the lower impact actually reduced the impact damage. Abdullah Ali 4z5 (talk) 03:34, 28 November 2023 (UTC)

No, it's not a blatant falsehood. Perhaps it's an oversimplification. In an intact building, the load per unit area of supporting structure would be more or less consistent (factoring in differing steel grades and allowable loads) as you assert. That would not necessarily be the case for an impaired structure. You're making a lot of assumptions concerning redistribution of forces in a compromised structure. However, I would prefer the detailed NIST analysis over the Times as a basis for any assertions concerning structural engineering and failure modes. Acroterion (talk) 04:10, 28 November 2023 (UTC)

I would also prefer NIST's statement (or at least something better than NYT). Do you know where they addressed this? Thomas B (talk) 06:22, 28 November 2023 (UTC)