WEBVTT - Hair on Fire, Part 1 0:00:03.080 --> 0:00:07.080 Welcome to Stuff to Blow Your Mind production of iHeartRadio. 0:00:12.720 --> 0:00:14.880 Hey you welcome to Stuff to Blow your Mind. My 0:00:15.000 --> 0:00:16.239 name is Robert Lamb. 0:00:16.200 --> 0:00:19.599 And I am Joe McCormick. And today on Stuff to 0:00:19.600 --> 0:00:23.520 Blow Your Mind, I wanted to talk about burning hair. 0:00:23.800 --> 0:00:27.080 That might be a kind of unusually niche or weird 0:00:27.480 --> 0:00:29.840 thing to look into. But I was inspired to do 0:00:29.920 --> 0:00:32.000 this a couple of weeks ago, on the fourth of 0:00:32.080 --> 0:00:36.320 July actually, when I was making food for a big 0:00:36.360 --> 0:00:38.000 family get together. You know, I was out in the 0:00:38.000 --> 0:00:42.120 backyard grilling, and I did something I have done many 0:00:42.159 --> 0:00:45.360 times before, which is burn all the hair off part 0:00:45.400 --> 0:00:48.239 of my arm. Oh no, yeah, turn and look. I 0:00:48.240 --> 0:00:51.879 mean like I wasn't like badly burned myself, like on 0:00:51.920 --> 0:00:54.480 my skin, but you know, at some point I looked 0:00:54.520 --> 0:00:56.400 down and realized, like, oh, what are all these weird 0:00:56.400 --> 0:00:59.560 little kind of pale curls. Oh I see? Okay. 0:01:00.520 --> 0:01:02.640 Do you say you've done this before? Do you at 0:01:02.680 --> 0:01:05.240 least alternate arms or is it just always the same 0:01:05.360 --> 0:01:06.000 arm that it gets? 0:01:06.280 --> 0:01:08.560 It's always my right arm because that's the arm I'm 0:01:08.640 --> 0:01:11.520 right handed doing that, you know, That's what I'm manipulating 0:01:11.560 --> 0:01:14.040 the food with. You know, sometimes it's more the hand, 0:01:14.240 --> 0:01:17.000 like the I don't know if it's gross to talk 0:01:17.000 --> 0:01:19.679 about your hand hair, like the hair on my knuckles, 0:01:19.680 --> 0:01:21.360 the hair on my back, the back of my hand 0:01:21.880 --> 0:01:24.200 that gets burned off. This time, it was mainly along 0:01:24.280 --> 0:01:27.080 like my forearm and the outside of my wrist. I 0:01:27.080 --> 0:01:30.800 wonder if other grill operators have had similar experiences, because 0:01:30.800 --> 0:01:35.640 I never burn my hand or arm hair when I'm 0:01:35.680 --> 0:01:38.200 grilling a small amount of food, like a couple of 0:01:38.240 --> 0:01:40.880 portions of whatever. It's always when I'm grilling for a 0:01:40.880 --> 0:01:43.800 big crowd. So I guess it has something to do 0:01:43.840 --> 0:01:46.840 with like trying to like fit a bunch of different 0:01:46.880 --> 0:01:50.000 individual items on the grill and then go down the 0:01:50.040 --> 0:01:52.120 line flipping them or moving them one at a time, 0:01:52.240 --> 0:01:55.280 and something about that means like I'm holding my arm 0:01:55.400 --> 0:01:58.160 directly over the hot part of the grill more or something. 0:01:58.560 --> 0:02:00.400 Ah, well, that that would make sense, because I was 0:02:00.440 --> 0:02:02.000 thinking about this, was like, Okay, I don't know that 0:02:02.080 --> 0:02:06.080 I've ever done this myself, but I think look back 0:02:06.120 --> 0:02:08.480 on all on the grilling I have done over the years, 0:02:08.800 --> 0:02:13.000 and it is generally just grilling for probably just for 0:02:13.080 --> 0:02:15.040 my immediate family. So it's feeling just for like two 0:02:15.160 --> 0:02:17.799 or three people, it's probably just going to be veggies 0:02:17.840 --> 0:02:21.359 that aren't on there very long. And yeah, for I 0:02:21.360 --> 0:02:23.600 guess a variety of reasons, and luck I have not 0:02:24.080 --> 0:02:27.360 like burnt a lot of arm hair on the grill, 0:02:27.440 --> 0:02:29.680 but I have to, so I have to ask like 0:02:29.720 --> 0:02:32.520 the follow up questions, like what you mentioned what it 0:02:32.560 --> 0:02:35.280 looked like, but that it was was that the primary 0:02:35.320 --> 0:02:37.200 way that you realize something had happened, or was there 0:02:37.280 --> 0:02:40.000 also like a skin level sensation And was there a smell? 0:02:40.400 --> 0:02:40.520 Uh? 0:02:40.600 --> 0:02:43.600 I mean, there's there's the feeling of heat obviously, which 0:02:43.840 --> 0:02:46.200 but that's just naturally the air because like I'm reaching 0:02:46.240 --> 0:02:50.560 over a hot fire, I think there is a smell normal, 0:02:50.840 --> 0:02:53.120 And in fact, I would say that the smell is 0:02:53.120 --> 0:02:58.240 probably the most characteristic and instantly recognizable sensory part of 0:02:58.280 --> 0:03:01.480 the burning hair experience. Right, I mean, almost anybody I 0:03:01.520 --> 0:03:05.480 think can immediately think of the smell of burning hair. 0:03:05.520 --> 0:03:08.359 It seems to stick in people's minds, even if hair 0:03:08.400 --> 0:03:11.320 burning is like not something that happens very often to them. 0:03:11.360 --> 0:03:13.480 It's just sort of I don't know, do you know 0:03:13.520 --> 0:03:15.200 what I mean, Like it just sort of like sticks 0:03:15.240 --> 0:03:16.880 in your memory what that smells like? 0:03:17.280 --> 0:03:19.960 Yeah, yeah, yeah, we'd be kind of wired, I guess, 0:03:20.000 --> 0:03:21.639 to recognize. 0:03:21.040 --> 0:03:24.120 It specifically in the context of grilling, though, there are 0:03:24.200 --> 0:03:26.079 already a lot of volatiles in the air, there's a 0:03:26.120 --> 0:03:28.880 lot of smoke, a lot of particles and everything. It's 0:03:28.880 --> 0:03:33.359 an intense smell experience already, So I think the smell 0:03:33.400 --> 0:03:35.720 of the burning hair, especially if there's only a little 0:03:35.720 --> 0:03:37.320 bit of it, just kind of blends in more. You 0:03:37.400 --> 0:03:40.040 might not notice that first. In this case. Yeah, I 0:03:40.040 --> 0:03:42.600 remember just like looking down at my arm, the part 0:03:42.640 --> 0:03:44.560 that had been hot, and being like, oh, yeah, that 0:03:44.640 --> 0:03:45.200 happened again. 0:03:45.960 --> 0:03:47.520 Okay that yeah, that would make sense. There are a 0:03:47.560 --> 0:03:50.080 lot of competing smells going on there. Yeah. 0:03:50.120 --> 0:03:54.360 But anyway, this experience got me wondering about the science 0:03:54.480 --> 0:03:56.960 of burning hair. I started to wonder, you know, some 0:03:57.320 --> 0:04:01.200 questions about the basic science and chemistry involve like how 0:04:01.480 --> 0:04:05.640 flammable is human hair, and why does it smell that way? 0:04:05.680 --> 0:04:09.840 And so forth. I was looking around for good sources 0:04:10.000 --> 0:04:13.000 on the on the question of the sort of the 0:04:13.280 --> 0:04:18.600 underlying chemistry of the smell of burning hair, and basically 0:04:18.800 --> 0:04:22.839 the best sources I found pointed me to the presence 0:04:23.040 --> 0:04:26.960 of sulfur. Of course, hair is mostly made of keratin, 0:04:27.040 --> 0:04:31.760 which is primarily protein, and of course those proteins, when 0:04:31.760 --> 0:04:35.200 they're burned, release their own sort of smells. There are 0:04:35.279 --> 0:04:39.200 characteristic protein burning smells that we might associate with the 0:04:39.240 --> 0:04:43.760 burning of other types of skin and even fingernails and 0:04:43.800 --> 0:04:47.280 things like that. But a big thing is the presence 0:04:47.360 --> 0:04:49.800 of sulfur. According to a paper that I'm going to 0:04:49.839 --> 0:04:54.960 mention in a little bit, human hair is approximately five 0:04:55.120 --> 0:04:59.960 percent sulfur, and that sulfur content is largely responsible for 0:05:00.120 --> 0:05:03.480 or the characteristic smell. And this is interesting to me 0:05:03.600 --> 0:05:06.880 because it explains a similarity at least as far as 0:05:06.920 --> 0:05:10.560 I can remember. That burning hair, to me, smells a 0:05:10.560 --> 0:05:14.520 little bit like lighting a match. Lighting a match produces 0:05:14.600 --> 0:05:18.919 the distinctive smell of sulfur dioxide or generally sulfur compounds, 0:05:19.680 --> 0:05:25.240 which happened because there is usually sulfur content in a matchhead. 0:05:25.320 --> 0:05:28.080 It's part of what burns to set the match alight. 0:05:28.480 --> 0:05:31.520 As a side note, apparently it is kind of known 0:05:32.400 --> 0:05:37.520 that you can temporarily mask other unpleasant smells. A commonly 0:05:37.560 --> 0:05:41.480 referenced one is the smell of feces by striking a match. 0:05:41.520 --> 0:05:42.599 Have you ever heard this before? 0:05:42.680 --> 0:05:44.760 Rob? Oh? Yeah, yeah, of course, you know. I mean 0:05:44.800 --> 0:05:50.160 sometimes even see that in at least residential bathrooms, you know, 0:05:50.480 --> 0:05:55.320 there will be like some matches out by the bathroom facilities, 0:05:55.320 --> 0:05:55.880 that sort of thing. 0:05:56.400 --> 0:05:58.560 Oh, that's interesting. I don't know if I ever made 0:05:58.600 --> 0:06:00.680 that connection, I would have assumed that if there were 0:06:00.720 --> 0:06:03.240 matches out, they're usually paired with a candle, and the 0:06:03.320 --> 0:06:06.279 idea is that you would use the matches to light 0:06:06.360 --> 0:06:09.279 like a pleasantly scented candle. And I always understood that 0:06:09.320 --> 0:06:12.520 as the ideas you would use a pleasantly scented candle 0:06:12.560 --> 0:06:15.640 to mask the smell of feces in a bathroom or something. 0:06:15.920 --> 0:06:18.840 I guess often but not always, I guess. And then 0:06:18.880 --> 0:06:21.720 there is also like the kind of just a saying 0:06:21.839 --> 0:06:24.200 right like oh, there's a bad smell that may be 0:06:24.320 --> 0:06:27.840 associated with digestion. Someone will be like, ah, somebody light 0:06:27.880 --> 0:06:28.600 a match, you know. 0:06:29.279 --> 0:06:32.320 Oh okay, Well, I may have misunderstood those sayings as well. 0:06:32.360 --> 0:06:35.839 I probably would interpret that as like, I don't know, 0:06:35.880 --> 0:06:38.000 what's the polite way of putting it, lighting a fart 0:06:38.120 --> 0:06:38.840 kind of comment. 0:06:39.200 --> 0:06:42.760 Well, I don't Well, I'm not sure that that was 0:06:42.760 --> 0:06:44.920 the level of excitement, like it's a bad smell in here, 0:06:45.000 --> 0:06:47.120 let's see if it can busts. It's more like there's 0:06:47.160 --> 0:06:49.640 an unpleasant odor. Let us light a match so that 0:06:49.720 --> 0:06:54.000 the smell of that struck match might mask the stink 0:06:54.000 --> 0:06:54.960 that has enveloped us. 0:06:55.200 --> 0:06:57.800 Yeah, okay, well, so now I'm understanding several things about 0:06:57.800 --> 0:07:01.719 the world differently than I did before this conversation. But anyway, 0:07:01.880 --> 0:07:03.599 so it makes me think about I see like a 0:07:03.640 --> 0:07:06.080 candle in the bathroom and some matches. Maybe I'm thinking 0:07:06.160 --> 0:07:09.800 about the mechanism differently. It's actually the lighting of the 0:07:09.840 --> 0:07:13.200 match more so than the candle that helps, sort of 0:07:13.240 --> 0:07:16.200 like calm your mind about the smells in there. But anyway, 0:07:16.280 --> 0:07:19.720 the idea is that the sulfur compounds released by striking 0:07:19.760 --> 0:07:25.240 a match overpower other smells in our olfactory recognition. I 0:07:25.280 --> 0:07:27.720 have seen it written in a couple of places that 0:07:27.800 --> 0:07:29.840 the idea is when you strike a match like it 0:07:29.960 --> 0:07:33.679 burns up the bad gases responsible for causing the smell 0:07:33.680 --> 0:07:35.320 in the air. That does not seem to be true. 0:07:35.320 --> 0:07:38.480 It's more kind of like your nose and your brain 0:07:39.000 --> 0:07:42.080 are primed to just let the smell of the struck match. 0:07:42.320 --> 0:07:44.960 I think this will be primarily the smell of sulfur dioxide. 0:07:45.000 --> 0:07:48.960 It just take over your smell sensing abilities. But it 0:07:48.960 --> 0:07:51.679 makes me wonder if the burning of hair also releases 0:07:51.760 --> 0:07:54.840 these sulfur compounds that are responsible for the characteristic smell, 0:07:55.280 --> 0:07:59.040 if you could likewise cover up the you know, these 0:07:59.160 --> 0:08:02.680 unpleasant bodies body aroma's, fecal smells and stuff by burning hair. 0:08:03.680 --> 0:08:10.160 Well we're not advising that, no, no, but just from 0:08:10.200 --> 0:08:22.640 like a chemical standpoint, okay, perhaps so. 0:08:23.040 --> 0:08:26.240 One of the most surprising and interesting things I discovered 0:08:26.320 --> 0:08:30.720 by looking into these questions about the science of burning 0:08:30.760 --> 0:08:33.080 hair was that some of the best research I could 0:08:33.080 --> 0:08:36.880 find on this came from studies about hair catching on 0:08:37.000 --> 0:08:38.680 fire in spaceships. 0:08:39.840 --> 0:08:43.640 Yeah yeah, attack ships on fire off the shoulder of orion, right, yeah. 0:08:43.720 --> 0:08:46.200 Yeah. So the main paper I was looking at is 0:08:46.240 --> 0:08:50.400 called the Flammability of Human Hair in Exploration Atmospheres from 0:08:50.440 --> 0:08:53.319 the year two thousand and nine in the SAE Journal 0:08:53.600 --> 0:08:58.959 International Journal of Aerospace by Sandra L. Olson, Devon W. Griffin, 0:08:59.240 --> 0:09:02.520 David L. L. Be, Gary A. Ruff, and Elizabeth A. Smith. 0:09:03.880 --> 0:09:08.079 And so the authors here begin by referencing an older 0:09:08.080 --> 0:09:11.040 study that I'll mention in a second that says the 0:09:11.559 --> 0:09:14.679 flammability of both skin and hair has actually been a 0:09:14.760 --> 0:09:19.760 subject of major concern since the early stages of the 0:09:19.960 --> 0:09:23.720 US BASE program, and they refer back to an older paper, 0:09:23.960 --> 0:09:28.040 one from nineteen sixty eight by Robert L. Durfey called 0:09:28.160 --> 0:09:32.160 the Flammability of Skin and Hair in Oxygen enriched Atmospheres. 0:09:32.480 --> 0:09:36.320 This was published in the OR as part of a 0:09:36.720 --> 0:09:41.160 USAF School of Aerospace Medicine technical report. This was from 0:09:41.200 --> 0:09:46.319 December nineteen sixty eight, and durfy begins this study from 0:09:46.360 --> 0:09:50.440 sixty eight by saying, quote, observations after recent fires involving 0:09:50.520 --> 0:09:54.800 human subjects in oxygen atmospheres indicate that the humans may 0:09:54.840 --> 0:09:58.200 have contributed to the spread of fires through combustion of 0:09:58.320 --> 0:10:02.600 their skin and hair. So obviously that's quite morbid. But 0:10:02.760 --> 0:10:06.560 I was wondering what this refers to, and I figured 0:10:06.600 --> 0:10:09.400 that since this was published in nineteen sixty eight, I 0:10:09.400 --> 0:10:11.720 think it almost certainly must be referring, at least in 0:10:11.760 --> 0:10:14.760 part to the tragedy of the Apollo one fire, which 0:10:14.840 --> 0:10:18.720 killed three astronauts on January twenty seventh, nineteen sixty seven. 0:10:19.040 --> 0:10:23.080 Those astronauts were Gus Grissom, Ed White and Roger B. Chaffey, 0:10:23.360 --> 0:10:25.640 and they died during a launch test that was less 0:10:25.640 --> 0:10:28.079 than a month before the scheduled mission, so they weren't 0:10:28.080 --> 0:10:30.840 actually in space. It was a ground test on Earth 0:10:30.920 --> 0:10:35.600 before the launch of an orbital mission. And the tragedy 0:10:35.760 --> 0:10:39.280 was that a flash fire broke out inside the cabin 0:10:39.320 --> 0:10:43.439 of the command module. The fire probably started with There 0:10:43.440 --> 0:10:45.520 could have been several ignition points, but it may have 0:10:45.520 --> 0:10:49.640 been an electrical arc from faulty wiring, maybe connected to 0:10:49.760 --> 0:10:52.760 some kind of chemical present like a volume of anti 0:10:52.800 --> 0:10:57.360 freeze fluid called glycol. But however it started, it spread 0:10:57.480 --> 0:11:02.280 very rapidly due to the enriched oxgen atmosphere pressurized inside 0:11:02.280 --> 0:11:05.360 the cabin. It was basically pure oxygen in there, and 0:11:05.559 --> 0:11:08.439 due to a variety of combustible materials spread throughout the 0:11:08.480 --> 0:11:11.199 cabin interior. Now, remember, as we've talked about on the 0:11:11.200 --> 0:11:14.360 show before, fire needs three things to burn. It needs heat, 0:11:14.480 --> 0:11:18.720 it needs fuel, and it needs oxygen. Obviously, in this scenario, 0:11:18.960 --> 0:11:21.080 there could have been an initial heat source, some kind 0:11:21.120 --> 0:11:24.840 of ignition point. There would have been lots of oxygen 0:11:24.880 --> 0:11:28.480 because it was a pure oxygen atmosphere inside the command module. 0:11:29.120 --> 0:11:32.360 And so the question is what was the fuel and 0:11:32.400 --> 0:11:36.000 what was the fuel roll of various substances including parts 0:11:36.040 --> 0:11:39.640 of human bodies inside the command module, and so this 0:11:39.679 --> 0:11:42.880 study was looking into human hair and skin, and so 0:11:42.960 --> 0:11:45.760 one thing it says that is that taken as a whole, 0:11:46.240 --> 0:11:51.880 even with enriched oxygen around, human skin is not especially 0:11:52.080 --> 0:11:55.280 flammable because it has a lot of water in it, right, 0:11:55.360 --> 0:11:59.199 So there is a major heat sink in human bodies 0:11:59.720 --> 0:12:03.400 where heat has to be continually applied from the outside 0:12:03.440 --> 0:12:05.199 in order for it to burn. There's a lot of water. 0:12:05.280 --> 0:12:07.640 That water must be turned into water vapor, so it 0:12:07.640 --> 0:12:12.400 doesn't catch fire easily. However, there are sort of little 0:12:12.559 --> 0:12:16.480 layers on the outside of skin and also hair which 0:12:16.559 --> 0:12:20.680 can catch fire in enriched oxygen environments much more easily. 0:12:21.160 --> 0:12:24.400 This study from sixty eight found that a high concentration 0:12:24.520 --> 0:12:27.480 of inert helium in the air in an environment, in 0:12:27.480 --> 0:12:30.800 this case seventy five percent helium, would prevent hair from 0:12:30.840 --> 0:12:34.880 burning at regular atmospheric pressure. And the study also tested 0:12:34.920 --> 0:12:37.760 various protective measures such as smearing the skin and hair 0:12:37.800 --> 0:12:41.959 with protective lotions and greases and covering it with flame 0:12:42.000 --> 0:12:42.880 repellent cloth. 0:12:43.559 --> 0:12:46.760 Was just shaving off all the hair just not an option. 0:12:47.520 --> 0:12:49.320 Seems like if I got to choose between the two 0:12:49.440 --> 0:12:51.439 for my space mission. I would just say, well, can 0:12:51.520 --> 0:12:53.200 we just buzz it all off? 0:12:53.559 --> 0:12:55.280 That is an option that is discussed in the two 0:12:55.280 --> 0:12:57.440 thousand and nine paper, which I'll come back to now. 0:12:57.520 --> 0:13:01.520 So yeah, So initially they cite the Derfy study and 0:13:02.280 --> 0:13:06.280 they say, as a general matter, there are several factors 0:13:06.320 --> 0:13:09.440 to consider that could increase the risk of fires within 0:13:09.559 --> 0:13:13.920 spacecraft or space exploration testing environments. And a big one 0:13:13.920 --> 0:13:15.680 they call out is the same thing we were just 0:13:15.720 --> 0:13:20.880 talking about, elevated oxygen levels. So in some cases ambient 0:13:20.920 --> 0:13:25.000 within spacecraft, but also in cases where supplemental oxygen is 0:13:25.040 --> 0:13:28.480 being provided through a mask. Now, when would there be 0:13:28.600 --> 0:13:32.640 supplemental oxygen inside a spacecraft, You could say, possibly in 0:13:32.679 --> 0:13:35.520 a medical intervention for an ill or injured crew member. 0:13:35.559 --> 0:13:38.880 They might have extra oxygen supplied to them. This is 0:13:38.920 --> 0:13:42.440 common in hospitals on Earth as well, or possibly during 0:13:42.440 --> 0:13:46.040 emergencies such as the leak of toxic chemicals or in 0:13:46.160 --> 0:13:49.720 fighting a pre existing fire. Now, the authors point out 0:13:49.760 --> 0:13:52.719 something interesting about the case of breathing pure oxygen through 0:13:52.760 --> 0:13:56.520 a mask. They say, quote, for every breath of pure 0:13:56.559 --> 0:14:01.680 oxygen breathed in, the exhaled breath still contains ninety five 0:14:01.800 --> 0:14:06.040 percent of the oxygen. This creates an environment of increased 0:14:06.120 --> 0:14:09.920 oxygen near the head and chest. Now I did not 0:14:10.040 --> 0:14:12.200 know that and don't think I would have thought about 0:14:12.200 --> 0:14:15.280 that before, but from what I looked up in other sources, yes, 0:14:15.320 --> 0:14:19.200 this seems right. In breathing say normal air on Earth, 0:14:19.240 --> 0:14:23.240 which is roughly twenty one percent oxygen and the rest 0:14:23.320 --> 0:14:27.200 is mostly nitrogen. In rough terms, that air on Earth. 0:14:27.280 --> 0:14:30.520 You know, if you say twenty percent is oxygen, about 0:14:30.760 --> 0:14:34.560 fifteen percent of the air you breathe out is oxygen. 0:14:34.880 --> 0:14:38.160 So what happened to that missing five percent of the air, Well, 0:14:38.400 --> 0:14:41.600 about five percent of the air is oxygen that is 0:14:41.640 --> 0:14:44.240 absorbed by the lungs. So when you breathe in, you 0:14:44.280 --> 0:14:47.160 absorb about five percent of the air, about a quarter 0:14:47.240 --> 0:14:49.800 of the total oxygen content of the air, and then 0:14:49.840 --> 0:14:52.960 that oxygen is replaced mostly with carbon dioxide when you 0:14:52.960 --> 0:14:56.080 breathe out. So that leaves you with what the author said. 0:14:56.120 --> 0:14:58.680 If you're breathing pure oxygen, say throw a mask in 0:14:58.720 --> 0:15:01.600 one of these scenarios, what you breathe out would be 0:15:01.680 --> 0:15:04.920 roughly ninety five percent oxygen. So the area around your 0:15:04.960 --> 0:15:06.880 head as you're exhaling is going to have a lot 0:15:06.920 --> 0:15:11.040 more oxygen in it than it normally would now note 0:15:11.080 --> 0:15:15.320 with regard to ambient oxygen, the oxygen levels used in 0:15:15.640 --> 0:15:20.520 different space exploration and environments have varied. The International Space 0:15:20.560 --> 0:15:25.760 Station actually maintains roughly the Earth's atmosphere mixture of gases 0:15:25.760 --> 0:15:28.600 in the air, so about twenty one percent oxygen. The 0:15:28.640 --> 0:15:33.760 rest is nitrogen, but the nitrogen has to be supplied 0:15:34.040 --> 0:15:37.640 through like bringing up tanks of nitrogen to make up 0:15:37.680 --> 0:15:42.880 that difference. So that and other considerations have led people 0:15:42.880 --> 0:15:45.040 to plan that in some other cases there might be 0:15:45.240 --> 0:15:49.560 higher levels of oxygen in the atmosphere breathed within space 0:15:49.600 --> 0:15:53.240 exploration contexts in the future. The author's cite a few 0:15:53.240 --> 0:15:55.960 other examples. They cite past examples as well. They say 0:15:55.960 --> 0:15:59.320 the Apollo missions and sky Lab used higher oxygen levels, 0:16:00.320 --> 0:16:02.520 and as of the time of this paper, there were 0:16:02.520 --> 0:16:04.880 plans for other missions that the authors say would have 0:16:05.000 --> 0:16:10.240 used higher oxygen concentrations. They cite the Orion Crew exploration vehicle. 0:16:10.720 --> 0:16:14.600 They cite the Altai Lander, which would have been at 0:16:14.600 --> 0:16:16.840 the time this mission was planned, would have been a 0:16:16.920 --> 0:16:20.240 landing vehicle for a US mission returning to the Moon, 0:16:20.720 --> 0:16:23.960 and they also talk about higher oxygen concentrations in possible 0:16:24.040 --> 0:16:28.480 lunar surface habitats, So there would be numerous scenarios where 0:16:29.200 --> 0:16:32.000 you're in a space exploration context and you would have 0:16:32.120 --> 0:16:36.240 increased oxygen levels. Either there's just ambiently increased oxygen in 0:16:36.280 --> 0:16:39.120 the particular mission or vehicle you're talking about, or you 0:16:39.200 --> 0:16:41.920 might be needing to give somebody oxygen for some reason, 0:16:41.960 --> 0:16:45.200 in which case there would be much increased oxygen around 0:16:45.240 --> 0:16:48.760 their head and chest. The authors also point out that 0:16:48.840 --> 0:16:53.920 certain medical interventions could provide ignition points, such as you 0:16:53.960 --> 0:16:58.480 could potentially start a fire during defibrillation, and this could 0:16:58.520 --> 0:17:02.120 happen even on Earth. Really, yes, I went and read 0:17:02.120 --> 0:17:04.880 about this. It seems to put some fears at rest. 0:17:04.920 --> 0:17:08.520 It is very rare. This is not something that commonly happens, 0:17:08.560 --> 0:17:12.760 but there have been reported cases. For example, the following study. 0:17:13.320 --> 0:17:15.879 I was looking at a study published in the Journal 0:17:16.000 --> 0:17:18.880 of the American College of Cardiology by Sanchez at All 0:17:19.359 --> 0:17:22.560 from the year twenty twenty three. It talks about a 0:17:22.600 --> 0:17:25.560 case where a seventy two year old male showed up 0:17:25.560 --> 0:17:30.719 at the emergency room. He was suffering atrial fibrillation an 0:17:30.840 --> 0:17:34.880 erratic elevated heart rate, and there were several interventions, including 0:17:34.920 --> 0:17:38.240 the use of a defibrillator to stabilize the regular heartbeat. 0:17:38.320 --> 0:17:41.280 So they put the leads on your chest and they 0:17:41.320 --> 0:17:44.600 send a charge to try to synchronize the muscles of 0:17:44.640 --> 0:17:49.560 the heart. The report says, quote, the defibrillator pads ignited 0:17:49.720 --> 0:17:53.520 in flames after the defibrillation button was pressed. The betting 0:17:53.560 --> 0:17:56.800 and oxygen mask also caught fire. Now that's something you 0:17:56.800 --> 0:17:59.800 don't usually think of happening. However, the author stressed that 0:17:59.840 --> 0:18:02.440 this is extremely rare. They say there are only two 0:18:02.520 --> 0:18:05.600 known cases in the medical literature that they could identify. 0:18:06.080 --> 0:18:09.879 And also fortunately the patient did not suffer actually suffer 0:18:10.040 --> 0:18:14.120 burn injuries. What was burned appeared to be the pads 0:18:14.320 --> 0:18:16.960 and the patient's body hair in some parts of the bedding. 0:18:17.320 --> 0:18:20.359 But they say to avoid this happening, there are several 0:18:20.359 --> 0:18:23.200 steps you can do. Of course, the increased oxygen from 0:18:23.240 --> 0:18:26.600 supplemental oxygen probably contributed here, so they say you can 0:18:27.359 --> 0:18:32.200 remove or place oxygen masks or nasal canula further away 0:18:32.240 --> 0:18:35.480 from the patient's chest when you're doing a defibrillation charge. 0:18:36.160 --> 0:18:39.239 They say that you can prepare the pads better, make 0:18:39.280 --> 0:18:43.760 sure that they have complete attachment to the chest wall. 0:18:44.240 --> 0:18:47.600 They say, chest hair should be trimmed ideally that that helps, 0:18:48.200 --> 0:18:51.000 and they also say avoid alcohol products during the preparation 0:18:51.119 --> 0:18:54.879 for the defib anyway, So that was sort of a tangent. 0:18:55.000 --> 0:18:58.800 But defibrillation is one of the scenarios the authors mentioned 0:18:58.800 --> 0:19:02.919 that could possibly provide an ignition point in space. But 0:19:03.359 --> 0:19:05.960 coming back to the burning hair in space study, the 0:19:06.000 --> 0:19:10.240 authors also mentioned cauterization as a medical procedure that could 0:19:10.280 --> 0:19:14.240 provide increased risk of fire in an oxygen enriched environment. 0:19:14.960 --> 0:19:18.919 So you pair the oxygenerate atmosphere in some spacecraft and 0:19:18.960 --> 0:19:23.320 space exploration environments with various ignition scenarios, and you've got 0:19:23.359 --> 0:19:26.879 the heat and the oxygen. So the third ingredient is fuel, 0:19:27.160 --> 0:19:30.000 and here the authors point to the presence of potentially 0:19:30.040 --> 0:19:34.480 flammable clothing and hair. Now in addition to the specific 0:19:34.560 --> 0:19:39.040 medical ignition scenarios mentioned above like defibrillation and cauterization, the 0:19:39.080 --> 0:19:43.280 authors note the conclusion of previous research, especially regarding Apollo one, 0:19:43.720 --> 0:19:48.840 that it should basically be considered impossible to eliminate all 0:19:49.040 --> 0:19:52.960 ignition sources in a spacecraft environment. You're always going to 0:19:53.080 --> 0:19:57.600 have things that could generate sparks or electrical arcs or 0:19:57.640 --> 0:20:02.159 hot surfaces so way to limit the risk of fire 0:20:02.760 --> 0:20:06.399 is to control access of those ignition sources to fuel 0:20:06.800 --> 0:20:10.440 by removing combustible materials or making them less combustible. 0:20:11.040 --> 0:20:14.639 You know, I've been watching enough alien movies recently to 0:20:15.400 --> 0:20:18.040 of course know that standard issue. If you're going on 0:20:18.080 --> 0:20:20.439 a space mission, you have a flamethrower on board, you 0:20:20.440 --> 0:20:22.840 have or at least a flamer unit. I don't think 0:20:22.840 --> 0:20:25.520 it's it's necessary. It's not nothing that's supposed to be 0:20:25.560 --> 0:20:27.879 like spitting jelly gasoline or anything like that, Like not 0:20:27.920 --> 0:20:30.840 a military flame thrower, but still a unit that shoots 0:20:30.840 --> 0:20:33.199 a big plume of fire at things. 0:20:33.840 --> 0:20:36.520 Why do they have that, That's a good question. Is 0:20:36.560 --> 0:20:39.480 there an industrial use or do they make them? Maybe 0:20:39.520 --> 0:20:40.600 they make them now that. 0:20:40.560 --> 0:20:43.360 I I think sometimes that's the case. But I don't 0:20:43.359 --> 0:20:46.119 know the best I could do putting this together, watching 0:20:46.160 --> 0:20:48.280 the films in the back of my mind, always thinking 0:20:48.320 --> 0:20:51.200 like flamer is probably not a great idea in an enclosed, 0:20:51.240 --> 0:20:54.040 sealed environment without even factoring in and all the stuff 0:20:54.040 --> 0:20:57.760 we've been talking about here. But I'm guessing you could 0:20:57.840 --> 0:21:00.639 make a case for okay, if you are dealing with 0:21:00.680 --> 0:21:04.919 some sort of a life form situa biological threat, like 0:21:04.960 --> 0:21:07.440 some sort of a bug, not a full blown xenomorph, 0:21:07.560 --> 0:21:11.000 you know, but just kind of whatever is expected to occur. 0:21:11.080 --> 0:21:12.679 Then I guess you can make a case for a 0:21:12.720 --> 0:21:16.080 flame unit. And then on top of that, if you're 0:21:16.119 --> 0:21:19.560 looking at some sort of a potential like boarding scenario, 0:21:19.880 --> 0:21:22.040 like a boarding action, like people coming on your ship, 0:21:22.040 --> 0:21:24.239 they aren't supposed to be there and you want to 0:21:25.640 --> 0:21:29.520 encourage them to leave or to back off, I guess 0:21:29.520 --> 0:21:31.639 a flame unit you could make some sort of a 0:21:31.640 --> 0:21:33.879 case that a flame unit is better than a gun 0:21:34.040 --> 0:21:37.199 that could potentially puncture the whole. But I don't know. Okay, 0:21:38.000 --> 0:21:40.000 once you factor all this in, though, is the risk 0:21:40.040 --> 0:21:41.679 of fire greater? I don't know. 0:21:42.200 --> 0:21:44.240 I think we'll have to assume that, like the Nostromo 0:21:44.440 --> 0:21:47.919 and other alien environments, just to use, they're more like 0:21:47.960 --> 0:21:51.040 the ISS, like they supply the nitrogen. They have a 0:21:51.400 --> 0:21:55.880 more earth like atmosphere rather than the oxygen enriched atmospheres 0:21:55.960 --> 0:21:58.320 that would increase the risk of using flames. 0:21:58.480 --> 0:22:00.680 Sure, Plus everything's a little bit wet than a stromo, 0:22:00.800 --> 0:22:02.159 so maybe that helps. 0:22:02.880 --> 0:22:05.880 Now. The authors of this paper note that a lot 0:22:05.880 --> 0:22:09.600 of individual mission durations are short enough that astronauts don't 0:22:09.760 --> 0:22:12.000 need to cut their hair in space, but even that 0:22:12.119 --> 0:22:15.959 does happen. Sometimes the space haircuts are real. They include 0:22:16.000 --> 0:22:18.920 a photo from the ISS of a space haircut where 0:22:19.000 --> 0:22:22.879 Russian cosmonaut Valerie Corzun is doing a haircut for the 0:22:22.920 --> 0:22:25.840 American astronaut Peggy Whitson in the year two thousand and two. 0:22:26.240 --> 0:22:28.159 And you can see like he's got the scissors and 0:22:28.200 --> 0:22:30.800 a comb in his hands and she's holding a like 0:22:30.840 --> 0:22:33.480 a hose up by her head. It's a vacuum cleaner hose, 0:22:33.720 --> 0:22:35.640 and I guess that's to suck in all the clippings 0:22:35.680 --> 0:22:38.280