The world's cleanest railway

At CEA-Leti, in Grenoble, there's a "funicular" that not many people get to ride: because it's between two clean rooms, and getting to it requires quite a lot of preparation. ■ CEA-Leti: www.leti-cea.c...
For most of my research on this, I'm indebted to this French-language article from by Julien Meyrat: www.vepres.fr/...
Camera: Simon Gillouin
Editor: Michelle Martin / @onthecrux
Local production by Block8 block8producti...
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[@TomScottGo]

This week's pinned comment is a plug for my podcast! It's called Lateral, and this week's episode has Mark Rober, Virginia Schutte and Jabrils. Listen for free at lateralcast.com or watch video highlights at kzbin.info

[@Sazoji]

two days ago? this just came out tho

[@AwesomeSheep48]

@@Sazoji Every video is the same, he posts the videos to youtube before they come out and schedules the release so the video is fully processed by the time it releases

[@ebixq]

alright scott

[@-off-]

At 3:30 you called this a funicular, as a funicular enjoyer I found this weird, as far as I can see there is only one "cabin". and it's not going up or down, either I missed something or you misspoke, it can happen to the best of us. Great video as always! Also, I listened to the podcast, good job, fun and interesting!

[@whatthehelliot]

mark rober? colour the spectrum mark rober???? kinds disappointed :/

[@B_-.-]

I'm starting to think Tom is a railway enthusiast

[@camerondent9390]

He has said that his backup plan if youtube didn't work out was to become a train driver

[@hughjass1976]

Tom is an infrastructure enthusiast

[@hyperturbotechnomike]

yes, but the monorail enthusiasts are still mad about him

[@Sand926e1]

this further explains the dream I had in which Tom Scott was run over by a train

[@tibbers3755]

Ayyyy! nothin wrong with that, plenty of room on this train if infrustructure fascination :D

[@speakfreely.1776]

My old teacher worked as a security guard and he accidentally opened an emergency exit for a clean room. Apparently this was a VERY expensive mistake.

[@lonestarr1490]

That's why he became a teacher then, where his mistakes won't matter that much anymore.

[@Boredom_Herself]

Ouch...

[@speakfreely.1776]

@@lonestarr1490 he was actually a former marine and a fantastic teacher.

[@FogelTheVogel]

I work in a cleanroom where we make medication, and that happens far more often than you'd think. Last time it was someone from QA who just *walked out the emergency exit*.

[@lemmingsgopop]

Depends on the level of the cleanroom but at minimum it will take several hours to wait for the air change, verify the indoor air, sanitize the equipment and then reverify the air quality. And usually you need a special QC team to take samples.

[@desk-kun]

Still loving how trains are always the cost effective solution for many problems

[@user-jk2zm7uq5s]

Isn't it (technically) a funiculaire though? (Is a funiculaire a train? A funiculaire runs on rails and is pulled by cables...)

[@theskilllessgamer5795]

Sorry to burst your bubble, but this is not a train but a single pod shuttle on some type of track. ;) But dont let Elon hear that.

[@logc1921]

​@@theskilllessgamer5795the hyper pod shuttle is an innovative idea by elongated musket to sink investor's money.

[@SECONDQUEST]

​@@user-jk2zm7uq5swell there is only planes, trains, and automobiles. It doesn't fly, and I can't drive it in the road. So it MUST be a train.

[@SerialElfYT]

@@SECONDQUEST What about boats?

[@Tehficus2]

I worked in the clean rooms at TSMC for a time and got to experience the corridor solution. Tom is right it creates quite a dismal environment, wish we had had a train!!! Great video though, it was fun to see all the tools again

[@Tehficus2]

Oh, and it looks like they get windows as well, deluxe!!

[@loganfong2911]

Just curious, how long is the corridor at TSMC?

[@unvergebeneid]

Although apparently you _can_ make a clean room out of glass as the people mover cabin demonstrates, so wouldn't that have made for a nicer corridor?

[@tonymorris4335]

@@unvergebeneid A handful of glass panels is easy to maintain and check seals on, a 1/4km of various windows and glass would be a lot harder to find leaks and troubleshoot.

[@SeanBZA]

@@unvergebeneid Cheaper and easier to make it from concrete and laminated boards, rather than run the risk of glass breakage closing the facility, and not having any windows also keeps heat loss and solar gain from making the air handling in the corridor have to run with a flow that will mean particles are lifted up off the ground. You want the air to come in the top at the right temperature, humidity and cleanliness, and flow down in a laminar slow flow to the floor, where it leaves via filtered ducts to be treated again. Glass will mean having to either make it triple insulated, with heavy filtering on it, and vacuum isolation of the panels, and also need much more cleaning to be done on the outside and inside to keep it clean. A small glass clean room, with a battery powered air handler, that only has to do circulation for 2 minutes in transit, before the air is handled by the main systems each end, is a lot cheaper, in that you only have to filter the air 3 or 4 times in the run, and not actually do anything else to it. The terminals can automatically connect to replace the air when stopped, and charge the small batteries that do circulation and light.

[@DomyTheMad420]

my single favorite type of engineering solutions is: "stuff that seems like overkill until you realize the least expensive option to fix the given problem."

[@paulthompson382]

It seems Tom has asked the entire world "any interesting trains?" and the world is answering. I love it

[@tehpanda64]

it occurs to me that clean rooms probably can't even use standard building materials, unless they have special paint or coatings to seal in the materials or something... Time to go down a rabbit hole. EDIT- for those wondering what building materials: epoxy resin poured floors, with aluminum honeycomb modular wall panels seems to be the norm. PVC is another common material. Even the doors need to be easy to clean so no wood.

[@KonradTheWizzard]

The building itself is normal industrial concrete. As you wrote: it is then coated with some kind of resin. Then another wall is built on the inside from lightweight aluminium panels. The floors are raised and have holes, so the air can go from the top of the building to the bottom in an almost laminar flow. On the inside there is no wood, no exposed concrete, nothing that can shed particles - just plastic and metal. The top floor or ceiling contains the filters, then the machine floor (usually level 3), then clean chemical supply, then general supply - cleanliness decreases from top to bottom. Going from standard industrial concrete building to clean room takes a few months.

[@Gunachov]

@@KonradTheWizzard Not always the case. You have described what an ISO 5 cleanroom would be, with technical flooring system. But not always needs to be this specific, nor does it have to be such a clean enviroment. Depends on the needs of the customer. But to sum up: -Usually built with sandwich panels, coated steel or fenolic resin with insulating material or structure inside. -PVC or resin flooring (Unless technical flooring is used). -At least 1 Air Handling Unit with at least 2-3 filters on the machine, if required terminal filtering would be installed on the room. -No sharp corners are allowed, as they tend to build dirtyness. -Doors are usually made from the same material as the walls. Just some quick hints of the needs, but depending on the use, different international rules must be followed, in order to be able to produce.

[@gigabyte2248]

My experience with university cleanrooms is that they're built as a plastic room within a room. All walls and floors are wipe-clean plastic or PVC. Getting non-shedding ceiling tiles is, apparently, a nightmare and they're nightmarishly expensive. What's also very important is to reduce corners for dust to accumulate in as much as possible - I worked in a cleanroom where the floor curved up into the walls. Figuring out an air current is important too: Tom mentioned that the cleanroom at CEA was at positive pressure but I suspect it (like the one I worked in) has the highest pressure in the cleanest zone (e.g. a photolithography room), working down to the 'grey room' spaces, flushing out dust as it goes. Grey rooms are places like the changing room which have the same walls/floors/ceiling as the main cleanroom but have no active clean air supply, relying solely on the passive flow of clean air from the cleanroom down to atmospheric pressure outside. I loved the room outside the changing room because the air felt nearly as clean as the cleanroom, but you didn't have to gown up. Temperature and humidity control is also super-important. The chemistry for semiconductor fabrication - particularly photolithography - can be extremely sensitive to temperature and humidity. If you're the lab manager, expect people to come to you asking 'can we turn the temperature in the cleanroom up/down?', to which the answer is always 'no, unless you fancy redoing every process recipe that's ever been done in there'. We had a problem with one of the air handling units, so spring and autumn usually involved crazy temperature swings and photolithography steps having to be repeated a few times before you got the definition you needed. Proper design and management makes a big difference for user experience.

[@KonradTheWizzard]

@@Gunachov Thanks for the clarification. I have only worked in ISO 4 and 5 rooms and I'm not an expert in keeping them clean - I test and automate the machines in there.

[@litapd311]

@@Gunachov just wondering, we hear a lot about microplastics and how they're everywhere. is there no concern that the plastic in the clean room will "give off" microplastics? or is it expected that any microplastics would be dealt with via the circulation and filters and such.

[@marvindebot3264]

11,000 sq metre cleanroom? Holy crap that's insanely huge!

[@dani33300]

104 meters by 105 meters.

[@dani33300]

Or 100m × 110m (easier)

[@alberthusby113]

@@dani33300 or 2x5000 metres (narrower)

[@trist308]

@@alberthusby113 or a circle with diameter 118.35 meters I shall go tie my shoes in the corner.

[@Kasiarzynka]

​@@trist308 What corner, you built a circle, they don't have corners 😂

[@Nalehw]

0:42 It's refreshing to see Tom miss his timing. Normally the vehicle he's talking about would miraculously enter shot right when he's ready to mention it.

[@candyman4769]

Selective attention makes few people notice, at least.

[@_Jess]

I think it still works since we have no idea what we're looking at, and need a couple of moments to register it

[@41052]

@@_Jessyeah I was tripped out by the moving box till he said that’s what it was

[@Yodah97]

Looks like he's cotaining his smile when the car shows up too, right? Probably because the plan was to time it right, and he missed it. Plus if he was a bit more late, the car would be out of frame by the time he mentioned it.

[@camerastooge]

Can we give some props to the editor/VFX artist who rotoscoped Tom over the blurred license plates in that open? I know it’s not THAT hard to do with current technology, but it would have been quicker and easier to just let the blur go over Tom. That little extra step is noticed and appreciated!

[@JohnSmithShields]

Moving a compass strikes again.

[@litapd311]

it's the small details like this that show the value of "quality over quantity". i best most people won't notice this detail that you did - but if the blur moved over Tom, then people would definitely notice

0:25

[@Tahgtahv]

Isn't it just camera focus? (Tom being in the foreground is sharp, and the cars being in the background are not as sharp?)

[@camerastooge]

@@Tahgtahv The license plates on the cars in the background are blurred - if you look you can see the edges of the box they drew around the plates. It was done to protect the owners of those cars, so you couldn’t look up who they were. Definitely intentional.

[@timbervalleyproductions]

As a Railway enthusiast, I love these railway videos Tom, keep them coming.

[@hanswoast7]

As a railway enthusiast enthusiast, I am very happy for you :)

[@Ikram232]

@@hanswoast7 As a railway enthusiast enthusiast enthusiast, I am extremely happy for you and wish you the best :))

[@lukasvondaheim]

​@@Ikram232 As a normal person I am very happy for the tree of you for being happy :D

[@nickkohlmann]

​@@lukasvondaheim :D

[@gnnascarfan2410]

@@Ikram232 As a railway enthusiast enthusiast enthusiast enthusiast, I am exceptionally happy for you.

[@pierrechausse3552]

Hi Tom, I work here at the CEA-LETI ! I love your work. Damn, such a shame to not have seen you.

[@KALE18]

Funny I did my M1 in Phelma with many of my classes on minatec and I don't know about this shuttle/train...

[@gamechip06]

*(inhales)* NEEEEEEEEEEEEEERD

[@mastershooter64]

​@@gamechip06 >feels insecure about his intelligence >calls people a nerd yup average youtuber commentor

[@pierrechausse3552]

@@KALE18 I did part of my study in Phelma too. Except if you visit the CEA, otherwise it is quite unknown. :)

[@gamechip06]

@@mastershooter64 no, I don't need anyone else to tell me I'm stupid, I already know that, but look at this guy; he is textbook.

[@memoryfoam2285]

Recently got a look into an improvement process for a clean room for a local engineering firm, they're moving from disposable suits to washable, much more comfortable ones, as well as improving exit and entry procedures. Very interesting thing to have to deal with in some industries.

[@SeanBZA]

Going to bet the washing has special detergents, and low doses as well, along with some serious water treatments. Likely also no ironing either, and no softeners at all.

[@kidneydealership]

@@SeanBZA spot on, the only problem with dealing with washable bunny suit is that the fabric near the button tent to tear up when undergoing the washing process

[@Luxfalcon]

I wonder if it would make sense to ditch any weak points with buttons in favour of a magnetic solution. Akin to a back zipper, one side of the clothing has a magnetic line contained within, while the other side has some fitting metal on the other side. Depending on what is done in the clean rooms, that magnetism might interfere with tested components though, so some amount of further insulation could be required.

[@KnugLidi]

I worked in a radiopharmaceutical R&D facility. While clean rooms are kept at higher air pressure to push particulate out, active areas in a nuclear area are at lower pressure to keep particulate in. When working with nuclear injectable materials, you have to do both. You set the clean room at high pressure, and an area of lowest pressure surrounding it. The main corridors are higher pressure than the low pressure area, but lower than the highest pressure in the clean rooms. Needless to say, the ventilation systems are complex.

[@chenzinc]

The fab at Micron Singapore has 2 massive, 150m long "corridors" connecting the old cleanroom to the new one. No windows, but wide enough for 2 small cars aside with tracks for automated vehicles on the ceiling!

[@CJT3X]

Is brake dust not a concern with the cars inside the clean room?

[@coulombicdistortion1814]

@@CJT3X You wouldn't find rubber tires that could shed particulates or mechanical braking components which could cause brake dust like that. Wheels would be solid plastic or metal on metal rails and braking components and propulsion would be electromagnetic.

[@jan.tichavsky]

@@coulombicdistortion1814 Metal on metal sheds particles too, especially in curves and switches. I can see it well on tram tracks in the city, there's plenty of metal dust inside the grove.

[@AnimatedStoriesWorldwide]

@@CJT3X He said "wide enough for 2 small cars" not "currently using two small cars with rubber tires".... fkin zoomers...

[@MuddyRavine]

@@CJT3X I believe the little wafer carrying vehicles are magnet powered.

[@Aramis419]

I live down the road from Merck, here in West Point, PA, USA, and one night at the pub, I met one of their scientists. “You could always work in the clean room, it’s pretty easy stuff.” And I sneezed all over the bar top. “Okay…probably not a good idea then.”

[@sarowie]

working in a clean room needs a special kind of people. Some jobs require highest attention, care and alertness, while others are literately perfect for people that are stoned, because the work required is slow and monotonous.

[@janzy58]

eww

[@prometheus7387]

Me with allergy problems: I don't think I can do this

[@kjl3080]

@@prometheus7387 I don’t think there’s anything you can be allergic to in the air of those rooms

[@gabor6259]

Do you have to have a degree to work in a clean room?

[@scottthomson4701]

Microelectronics student here. Cleanroom protocals are no joke. We had a sticky mat just by the entrance to remove anything on the bottom of our shoes.

[@LapanConnor]

the fab I work at has brush wheels you need to use to clean off your shoes before donning your gear, and sticky pad in the one area that I know of where you don't wear shoe coverings.

[@queeny5613]

We have one in the controlled plant science lab for pollen and seeds

[@soffa93]

we have those, but our cleanroom still lets us wear our own pants under our labcoats (coats, not overalls)... we only work in fume hoods though

[@richardnavratil9661]

The shot framing and production value of Tom and his team are crazy. Love seeing these interesting stories

[@Yodah97]

Incredibly, it's usually either him alone or him and one guy. When he's alone, he asks someone on location to hold the camera. I'm guessing he's mastered the art of helping random people frame him right. Either that or he shoots slightly wider and then crops in the right frame in post.

[@SarimDeLaurec]

I work in a pharmaceutical cleanroom and I am so happy we are allowed more particles than cleanrooms for electronics and stuff. I think the highest standard would be comparable to ISO 5. A higher standard would make no sense though, since you would already have achieved a sterile environment. Just going from one GMP suite to another on the same floor is enough hassle with ISO 7. Just thinking about a long corridor from one building to another and the cleanup process for that would give me anxiety. :D That small car seems way more practical.

[@KonradTheWizzard]

We are concerned about different kinds of particles though. In Semi we don't care much about viruses and sterility. We care about stuff that can sit on top of wafers and make transistors go bad.

[@shanekeenaNYC]

@@KonradTheWizzard Various dusts and pollens come to mind, not to mention water droplets if the day is particularly misty/muggy out.

[@ashliehiggins]

I used to work in BSL/CL3 labs (ie the complete reverse of a clean room to keep stuff in rather than out) and experienced touring a ISO7 you clean room guys deserve way more respect as it’s nuts spending hours in them.

[@KonradTheWizzard]

@@ashliehiggins Thanks! But you get used to it after about a year. (That, or you'll quit and never look back.)

[@scottdonovan4841]

I'm definitely glad to work in probe so we don't have to deal with all this as well. It's annoying enough having to unsmock just to go in the shop and get parts.

[@Smox]

The scene at 0:41 where the cabin goes behind Tom as he introduces the whole concept was so cleanly done

[@evanlucas8914]

It's interesting to see the different clean room protocol. In this environment they're worried about particulate matter, microorganisms don't really factor in. So clean clothes and full body covering to catch shed skin cells are enough. In biosafety level 3 labs they're worried about pathogens infecting humans so the human becomes sealed from the room in its entirety. in surgical operations they're worried about microorganisms getting from tools and surfaces into an open patient so everything is new from a package and single use, thoroughly sterilized, and hands and mouths are covered. The surgical scrubs are more about keeping the patient off the doctor than about keeping the patient from getting infected.

[@matthieuzglurg6015]

hey I worked here ! Had the occasion to take the "clean train" twice, that was pretty amusing even though I don't usually work in clean rooms. We always saw it going over us when we were walking towards the company restaurants (you can see it right behind the blocky clean rooms on the left of the road in the final shot)

[@zapfanzapfan]

What fascinated me the most when I visited a really extreme clean room was that the water pipes and faucets were Teflon coated plastic to not get any metal ions in the water.

[@supidosan]

It's nice to know that those workers got such good perks! A steady supply of teflon, any time of day or night. Yum!

[@maddog2314]

Tom, the amount of crazy niche things you find in this world blows my mind. As someone who has had a scientific education and been in a couple clean rooms myself, I never would've imagined to even look for something like this. Incredible.

[@iGleeson]

I just love getting to see all this mad, purpose-built stuff that we'd never, ever see without Tom Scott.

[@breaux2806]

I work in pharmaceutical grade cleanrooms up to iso-5 and seeing how fast they walk around, having their faces exposed, sitting down while gowning, and not keeping their hands in first air is giving me anxiety. Also, I would absolutely hate having to maintain a cleanroom that huge. We do daily cleans with Decon-cycle on the walls, horizontals, and floors. Weekly cleans with Decon-spore on everything. Twice monthly cleans with Decon-clean followed by decon spore and alcohol on the ceiling hepa filters. And resto cleans that are two courses of cycle followed by spore and alcohol. Trying to imagine keeping that large facility to the standards I work in is painful.

[@thomasfrench2012]

I know that you said that there were places you weren't allowed to go. But Ironically, that must be one of the funnest parts of doing these types of videos, being able to go where most of us can never go. Other than those who already work there, it is highly unlikely that anyone else watching this video will ever be able to do what you just did - and for very good reason.

[@experiment8230]

I work at an Intel cleanroom that's literal MILES long. What I wouldn't give for a train in there...

[@crackwitz]

Air Hockey sled? There must be ways to accommodate.

[@soscler]

I am so happy you finally came to Grenoble.. I hope you're still here and would talk more about the city, (one of the most bike friendly in France), the food (Gratin dauphinois) and of cource the european synchron, etc.

[@y_fam_goeglyd]

That is a genius idea! Whoever came up with it must have been seriously cheesed off with the whole preparation rigmarole, but coming up with a "clean train" is still out there. I'm thoroughly impressed!

[@johanburet5041]

The Poma company, that manufactured the clean room cable car, is specialized in building ski lifts for the resorts surrounding Grenoble. It's also a local company, based in Grenoble.

[@NIDELLANEUM]

"The source of contamination is us" sounds way smoother in a French accent

[@yes_jay_dee]

0:55 the composition of this shot is amazing!

[@Chris-ok4zo]

I imagine this is like being in a space shuttle docking between two stations and (maybe) hearing that distinct "hiss" as the air pressure stabilizes or something. Very cool nonetheless.

[@KingRCT3]

Yay, a Poma shout-out. I wish you can pay a visit to them since they're in the same region. Ropeways are so cool.

[@Dave_Sisson]

I clicked just on the preview, because I was sure that it was made by one of the giant ropeway companies. I agree with you, it would be great if Tom and his team produced more videos on ropeways!

[@AaronShenghao]

The amount of HVAC work to make sure a clean room works as intended is tremendous. To make a corridor that long you need At least 2 filtering and air-conditioning systems (one primary one backup). Factoring in the required duct length, you actually going to need 2 sets one on each end…

[@Rubrickety]

There’s always something ineffably delightful about the sound of someone with excellent English but a strong accent.

[@Combicon]

Working in a more standard cleanroom (that manufactures chemotherapy) - this was super interesting! I was really curious as to how the door would get clean and trying to come up with ways that would work, and their solution was much simpler!

[@MadBiker-vj5qj]

Now we just need Geoff Marshall to make a "Least Used Stations On The World's Cleanest Railway" video to complete things...

[@Scruffi]

Although as this is in France, I might expect Tim Traveler to beat him to it :)

[@timothymclean]

I am curious which of the two stations is used less.

[@HenryLoenwind]

@@timothymclean The one the cleaners are not accessing the carriage from... ;)

[@vigilantcosmicpenguin8721]

@@timothymclean When you've only got two stations, it would be impossible to use one station without using the other.

[@YEASTY_COMMIE]

I worked there ! I've been on that little mover when I visited the clean room. I worked for LETI on the last floor of the building in the right corner at 5:14, good times

[@Brigtzen]

Human engineering and ingenuity will never cease to amaze me.

[@basecius]

I'm surprised that the doors opened that way. I expected them to connect to each other and open together. That way there would be less outside surfaces in contact with inside air.

[@MazeFrame]

Same actually. The "Seal together to have the pocket of dirt out of the way" seems like a possible upgrade.

[@mskiptr]

Also thought about it. The issue I see is "how do you move the two doors out of the way?".

[@mjordan812]

And today I learned why the Poma Lifts that I rode up ski hills in the late '60s were called Poma Lifts. Never really gave it much thought over the past 50+ years.

[@euansmith3699]

Don't feel bad about yourself, Airlock; I'm exhausted by fresh, clean air, too. Another wonderfully weird and entertaining video from Scott! 😎😍

[@naturalcauses1695]

1:57 Damn, not even my birthday and he still brought the cake

[@Infamouslbx]

We have multiple clean rooms in my company, some separated by nearly 2km, we had a similar issue. So they built a massive pneumatic tube system. It works great, and keeps our areas clean. I'm surprised they didn't use that here.

[@srpacific]

When I worked in the elevator industry we went to a lot of hospitals to do assessments/audits. The surgery prep room had a dedicated elevator that went to the operating theatres, and it was a full clean room including the elevator itself. The used implements got their own elevator too, and it went from the operating rooms to the disposal/cleanup room. Guess what? Both elevators shared a single hoistway and were not separated at all……

[@firesurfer]

I used to install entrances and I only did a few single stop entrances. The Marriott Marquis at the top to the restaurant, for the kitchen and staff, a couple penthouse ones and a private one in a brownstone for a handicapped professor. I almost forgot an odd one in the -6 sublevel at 7wtc.

[@crackwitz]

OR "clean room" protocol is just about keeping the air free of dust and airborne germs, and that stuff off the patient, also germs off anything that touches the patient. Used instruments are assumed to need autoclaving but they don't pollute the air.

[@OriginalRaveParty]

You bring some of the most interesting things in the world to the public's attention. Awesome as always.

[@benbauer3426]

I remember working in a clean room making O2 masks, a few years before the pandemic. Lots of interesting, specialized equipment. LOTS of filters and air conditioning.

[@JoeMangleWins]

It amazes me how there are clearly two classes of human and how vast the differences are between the two, on one side you have amazon workers and miners expected to go through what they do on a daily basis and on the other you have people that are worried how other people might feel about walking down a corridor with no doors in which you can't see the end.

[@NIGHTOWL-jf9zt]

For 4 1/2 years I walked a square corridor 800 feet long with no windows, florescent lighting, NO talking and NYSDOC grey six times a day. One can get used to it.

[@rosslmccallum]

Video quality is really awesome!

[@OldLando]

Only Tom could make a 'clean railway' interesting.

[@user-tzzglsstle585e38]

wdym, this is interesting even by itself

[@toritwopointoh]

all due respect to Tom but I’m watching this vid bc i think a clean railway is interesting

[@davidioanhedges]

Only Tom could make anything interesting ... he does start with only interesting stuff however ...

[@pvic6959]

he can mane interesting stuff 5x as interesting bc he gives me history of it

[@user-tzzglsstle585e38]

@@pvic6959 Not discrediting Tom here, but if anyone's gonna talk about something specific (like this one); telling their history is like a default anyway...

[@cattict5378]

there is something so addicting about these videos, it is perfect. it is just so much knowledge gained in small time, its great!

[@hughcaldwell1034]

My partner's illness means we have to be very careful about what gets into our house. It's not clean room standard, but I definitely empathise with the gowning and re-gowning rigmarole, not to mention all the wiping of surfaces. I've definitely wished for an airlock a time or two.

[@Ark-ju2gt]

The great thing about Tom Scott is I learned more about my countries technology with him than with newspapers, even about companies I'm familiar with.

[@Sarahbryson321]

How odd. A railway between 2 rooms? That’d be my ideal house

[@humorss]

@Smee Self it be a nightmare installing kitchen and washrooms on small rail car

[@vigilantcosmicpenguin8721]

I would prefer a slide between rooms, but to each their own.

[@bastienchalvin5242]

Hey, i'm from Grenoble ! I didn't expected to see my town in your video one day. It really make me happy Also, i didn't even know for this clean railway. Thanks for this video !

[@firesurfer]

Interesting. I spent 12 years as an elevator entrance installer. I've never seen a gap filler like that before. 5:09 Looks like it's for a @ 1 1/2'' (40mm) space. The taper is obviously because it goes sideways not up and down. The cab doors are strange looking. I guess because it's designed to be positively pressurized when in use. It can't be sealed.

[@clancybenedict6647]

I'm confident in saying Tom is by far my favorite KZbinr at this point. Has been for a while now--this sealed the deal though. Thank you for your videos 🙏🏼🎉 You have no idea how much impact they have.

[@carlchapman4053]

Tom - I'm not allowed through this door, let's go back. Also Tom - Another go on the clean room funicular, Yippee!

[@nikolaimikuszeit3204]

Worked at CEA 10 years ago and had a chance to see the clean-"room". Mind-boggling. Didn't do the train ride, though ;) Quite difficult to get permission to get into CEA....guess it was hard work to convince them to do this ;)

[@cihanbuyukbas7333]

Tom and Trains. Two things that go hand in hand!

[@matchstikman3034]

I love your curiosity! And how much fun you have making these videos! Your team is Excellent!!!!

[@kn0bhe4d]

This looks extreme, and you hear the guy say that they're deal with 10nm fabrication.....and then you realise that there's 5nm fabrication that's going on these days. If 10nm fab has this level of care and attention being needed, just how extreme is 5nm production?

[@elijahgrean]

I think they've made stuff down to two nm now which is absolutely insane and I can't even fathom how a transitor works on that scale.

[@richardmillhousenixon]

At that point it's probably almost entirely automated, just to eliminate the human element (the element most likely to introduce contamination) as much as possible

[@JohnADoe-pg1qk]

With regard to the clean room, the requirements should not be much higher, because I think any natural dust is already many times larger than the 10 nm technology mentioned in the video.

[@jan-lukas]

The different nm fabrication techniques are actually not really accurately named. The x nm technology of one company can be the equivalent of y nm in another company. But yeah, the requirements get much stricter with each node upgrade

[@nathangamble125]

The particulate requirements are about the same. At any scale, a hair or particle of dust will ruin the circuitry below it, whether you're working on a 280nm, 10nm, or 5nm node. The difference is in how complex the etching process is - more advanced and denser processes use higher frequencies of light, and require more consecutive passes, in order to produce smaller structures with a much greater level of precision.

[@BWWWAAALORDOFDUCKS]

What a great job. Being able to travel around the world to look at interesting things and expose the world to wonders not captured by general media would be in itself an awe-inspiring experience.

[@prospectnyc]

0:42 this shot is so cool

[@vladspellbinder]

The "I am not allowed in this door. I can't do the walk off in to the distance." is a great way of ending the video.

[@vigilantcosmicpenguin8721]

It's the second-best way of ending a video, behind actually doing the walk off into the distance.

[@91JLovesDisney]

New camera? Cinematography looks amazing!

[@KonradTheWizzard]

No, he had to clean the lens before he could enter the clean room with it. 😛

[@_eric]

My hometown ❤🇫🇷. Merci Tom for putting us on the KZbin map 😉

[@Wico90YT]

Tom being awkward about locations is the best part

[@fencingboy101]

This guy has the funniest French accent I’ve heard in a long time

[@SemiHypercube]

Really neat solution to a special problem

[@ca-ke9493]

Ive also experienced the corridor solution, they are everywhere at where i work. It's a really sureal experience and most people would ask someone to come with them. We have much bigger equipment and interconnected links so i think the corridor made a lot more sense.

[@TheKingReto]

But what about eyebrows at 1:50?

[@caput_in_astris]

Oh how lucky you were! I have been to the Leti (gas sensor project) but we were not allowed into the building, not to mention scrubbing…. We were only allowed in the conference rooms which are not connected to the main building. Thus thank you for having shown the interior 😊

[@JaykPuten]

2:07 but it is only a *wafer* thin

[@ceno10101]

I used to live in Grenoble, it was nice to see the city again in those wide shots.

[@PaulPaulPaulson]

Tom wasn't allowed into the other clean room at the end, but not because they were concerned about the clean room. They were concerned about Tom after they saw his cave video 😉

[@roddyk05]

I used to do maintenance in and on a semiconductor clean room. It’s surprising just how dirty they can be but as long as the working areas of the machines where the wafers are handled are clean then it was usually ok.

[@suspense_comix3237]

For some reason, I expected Switzerland or one of the Nordic Countries to have the world's cleanest railway.

[@LHyoutube]

Or Japan.

[@crazydinosaur8945]

​@@LHyoutube we mean clean, not on time. railway

[@sarowie]

well, switzerland would have built a tunnel connecting the two buildings. And the tunnel would be certified to survive a nuclear blast.

[@charleskramer9958]

I am always so happy to see tom scott uploads

[@adiuntesserande6893]

And here I thought Swiss trains were clean!

[@muddydave01]

Dad, a fitter, turner, scientific instrument maker, master welder by trade, was the lead on a team that retrofitted a commercial clean room to make it clean enough for nano-fabrication and semi-conductor research. Things like building service line terminals that didnt have gaps and filleting bench tops so dust couldn't adhere to the corners.

[@BarteldsJunior]

Someday Tom will have shown everything interesting on this earth... that will be a sad day!

[@sarowie]

well. there is still the ISS, the moon, ....

[@agimasoschandir]

No, I think there is at least one more interesting thing TS will not get around to. Don't know what it is, but at least one more thing

[@diablito2013]

Keep ut up! Been waiting for this day! 🎉🎉

[@sunimod1895]

So the opposite of nyc subway

[@XE1149production]

And the London underground

[@Nyx773]

And the Chicago L

[@jerryglazman260]

I am continuously amazed at the unique "stuff" you find. Another video that told me something I didn't know before.

[@lauramcelhiney]

GlazMan

[@OrbitalCookie]

I wonder if this was just an elaborate excuse to ride a train at work.

[@Reve42]

As a French person, hearing French people speak English is one of my favorite things.

[@ShrirajHegde]

Wow I worked here. This area is highly against recording. Even blurred on Google maps. There was a double rainbow, I tried to take a picture and the guard came running since the facility was in the shot 😅

[@loscheninmotion9920]

wow that's actually really interesting!

[@DjesonPV]

As most of french Governmental assets. If you want to see a satellite view, use a non NATO source (for example from the russian Yandex )

[@victoriaeads6126]

I appreciate that one of the considerations for the train vs a corridor was the mental impact on the people using it vs using the train. Sure, cost is important, but people are more important.

[@CakeboyRiP]

This is a true gadgetbahn but this one has purpose

[@SanderEvers]

So it's not a gadgetbahn. It's actually the simplest solution to the problem.

[@Darkanight]

I love your enthusiasm about everything... It's contagious!

[@Tenecifer]

Too bad that you didn't go to the "Bulles de Grenoble", it's THE attraction of the city and it's quite unique 😁

[@Loweene_Ancalimon]

Who knows, he probably did ! Hope he did. I don't think we'll get a video about them, beyond looking cool they're nothing exceptional from an engineering standpoint, but I hope that Tom and the team took the time to take them while they were in town !

[@jacob_90s]

Thanks for addressing the interface problem. Was wondering how they handled that

[@laurentderrien]

that slight and delightful french accent :D i'm proud of my fellow frenchman

[@thi6aud]

OUEEE GRENOBLE

[@GoskopeEducation]

this is great video tom. well done