How a fire sprinkler works. (featuring broken glass and spatter.)

I didn't realise you could buy sprinkler heads on eBay until I was looking for something completely different. Being fond of workwear I was trying to find an American supplier who would ship a Carhartt R28 carpenters overall to the UK. I discovered that particular style of overall is very popular with mechanical trades because of the built-in tool pouch. That makes sense as standard tool belts are prone to slipping down your waist when loaded with tools and hardware.
Seeing images of sprinkler fitters wearing them then reminded me of how intriguing fire sprinkler heads are. Especially the mysterious little vial of coloured liquid. So it turns out that you can buy them from China on eBay from the electronic component suppliers. And they're very cheap, probably because they're a mass produced item. Apparently 40 million sprinkler heads are installed every year. It's also interesting to note that buildings with sprinklers tend to have 96% of fires extinguished by the sprinklers alone.
With these accessories readily available it opens up the possibility of fitting your own home sprinkler system in critical areas like workshops, and just hooking it up to the cold water supply if it has good pressure.
I did get the overall. It's really rugged compared to typical European workwear.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
www.bigclive.co...
This also keeps the channel independent of KZbin's advertising algorithms allowing it to be a bit more dangerous and naughty.

[@davidwebb2318]

"It might not go very quickly....oh". Another classic Clive video...

[@pinterelectric]

I work for a pharmaceutical company and the covers are used in clean, sealed rooms that have positive pressures to keep the dust out.

[@eliotmansfield]

Jeff Pinter Also used in server rooms as you need to maintain integrity of the room

[@psirvent8]

Eliot Mansfield No, usually server rooms are equipped with water mist or gas systems. To prevent water damage of course. And the heads of those systems are not concealed.

[@LOUDcarBOMB]

I would think that it would be trying to fight electrical fires since they have to be fought in a different way. I bet the servers would be toast when the fire is cooking them (don't know a proper way of saying it).

[@copperhamster]

@@LOUDcarBOMB Magnetic spinning drives can be recovered after being subjected to hundreds of degrees C with enough dedication. SSD's even more so. A dedicated data center fire suppression system usually sends an emergency shutdown to the servers at one temp, a kill switch to all backup power at a higher temp, and finally trips the water. In some states halon, co2, etc systems are now illegal because people have been killed by them. In mine they're illegal for new installations

[@blameburr8722]

@@copperhamster some may use Halon gas, it really does vary but you can buy a lot of these things anyway (,such as CO2) so I can't understand why they'd be banned except for Halon.

[@LaterMeansBrick]

Many modern systems use a "dry" sprinkler system. They are pressurized with air, as soon a detector notices a sudden pressure drop (a single sprinkler pops) high volume pumps start up and all hell breaks loose. The dry system has the advantage that the water inside won't go septic i.e turn into a stinky brownish soup that smells like crap, when not in use.

[@RSOFT92]

The "dry System" you are talking about also has the advantage that it can be installed outside (e.g. in a car park) without the danger of freezing water in the pipes.

[@LaterMeansBrick]

The one I saw with my own eyes was in a big-ass sawmill, in the main building. Due to no heating and great drafts in winter. They were connected to 4 enormous pumps, those also had a backup generator in case the power would fail. They were doing some testing, the amount of water those things pumped out was staggering.

[@andrewholdaway813]

RSOFT92 That's the usual reason for a dry system. No reason why a wet system should become 'septic'.

[@andrewholdaway813]

LaterMeansBrick Deluge systems can be positively dangerous to be caught in - you could suffocate.

[@jaredd9297]

Dry systems are used for cold areas they cannot remain heated. Water in wet pipe sprinkler systems can get a little Skunky after a while, but after flowing for a couple moments it is clear. Wet systems are more advantageous because water is at the point of ignition instantly.

[@drusha]

It would be pretty ironic, if there would be flammable liquid in a fire extinguishing sprinkler glass pellets.

[@koosnaamloos]

Im gonna make sprinkler heads now with flamble liquids

[@stanpatterson5033]

Uncle Stalin, you'll be really popular with the insurance companies :)

[@TehMG]

The amount in the glass vial is so small, in the grand scheme of things even if the liquid is flammable, it will have a negligible effect on the spread of fire, especially since the liquid is soon followed by vast amounts of water!

[@throttlebottle5906]

in wet pipe system not flushed often, the water can separate into oxygen and hydrogen gases, when it release you get pockets of highly flammable gasses. vast majority here is dry-type systems, so they don't freeze up in unconditioned spaces. and not to forget, some may have had alcohol as antifreeze. booo

[@davidturbo8566]

MGKZbin Account the flammable effect would be so vague ..

[@highdesert50]

If I remember correctly from fire classes, the vial is called a frangible tube and contained alcohol. Keep in mind the hot air rises and temperatures at ceiling level can be hundreds of degrees higher than at floor level. Hence if you are ever in a house fire, roll out of bed, don't sit up, and exit low.

[@OZf1re]

highdesert50 interesting that Australian standards state they only contain water, might be different per region

[@chriseber7714]

Yet when they freeze and blow without there being a fire, the mess is just as big, if not bigger to clean up in the end

[@TorqueSlayer]

@ADEBISI ADEBISI fuck you bitch

[@eddeh0772]

No idea how I came across this video, but “a pride flag of explosive liquid capsules” has such an oddly lovely layer of poetry to it, and your observations were surprisingly interesting. I’ve literally never thought about sprinkler systems before this, but learnt a lot. Great video, thank you!

[@Richard-zu3gz]

Don't suppose you could point the heat gun at the cover and see what happens?

[@GigsVT]

Richard Berridge I popped a fusible cover off a heat sensor trying to test the rate off rise without popping it... Its somewhat anticlimatic. In my case my reaction was whelp there goes $20. I did get to take it apart after. Clever simple mechanism in heat detectors.

[@Spartacusse]

I think it's more likely, because it's cheaper and easier to manufacture, that instead of melting the metal tabs holding the cover, it's actually supported by a very thin metal bent inwards, when the whole case becomes like an oven from the heat, the glass breaks and and just the water weight is enough to unbend the metal tabs and release the cover. The drop down defuser looks like it's purpose is to stick out of the case to spread the water, but even before it's allowed to drop down, when the glass breaks the whole case is already filling with water.

[@al35mm]

Wouldn't they be bimetalic strips that will bend with heat?

[@jaredd9297]

To cover drops off 20° before the head activates. So with a head that is 155°F the cover drops off at 135°F. Those just are solder points where he was pointing.

[@rich1051414]

Pretty sure the covers are soldered on under leaf spring pressure, so the instant the solder melts, it pops off with force, albeit, very light, unspectacular force. Just flings off and hits the cook in the head. :) (Since the only place I have seen them was when I was a cook, and once one popped off and flew right at me in the middle of dinner in a packed house). Thankfully, the glass part didn't pop, just the bottom part with the cover. I can confirm that the bottom cover releases FAR before the glass does. I assume that one popped loose too early because the solder was old, but at least it fails by breaking loose when it shouldn't instead of not breaking loose at all when it should.

[@tobylatino8737]

This guy has a way of asking every possible question and i love it

[@twocvbloke]

A damned firework went off nearby right as that vial popped, didn't half make me jump... :S But that aside, you'd probably want to have a separate water supply for the sprinkler system, such as a header tank system, this way you wouldn't contaminate the mains water supply given that most sprinkler systems are unused for years while they're filled with water that is going yucky... :)

[@bigclivedotcom]

Theoretically for a home system the pipework could form part of the normal supply, so water flowed through it continually on a daily basis.

[@twocvbloke]

I suppose that could work, the only thing I'd be concerned about there (as mentioned in other comments) is pipe knock, where something like a washing machine suddenly stopping the flow of water could damage the sprinkler valve, or at worst, pop the vial from the physical shock, probably something worth testing there, outdoors of course... :D

[@Peter_S_]

It's worth noting that these may be built using a leaded alloy which is banned in the US for domestic water supplies. They used to make most faucets from such alloys because they form good seals and they're easy on the mill tooling, but they've since been banned.

[@danohstoolbox]

It would have a check valve in line of the supply line

[@rockinatmidnight]

Doubt it would be set from a header tank or similar set up. Could still save your life, then kill you from Legionaires!

[@benhawkes2752]

When I saw the cap I realised I had finally accidentally found the answer to the question I always had “wtf is that plastic circle on the roof”

[@wauser5456]

In the apartment I'm in, they've painted over the sprinklers and the tubes with it. Seems like asking for trouble if the coating is thick enough. Maintenance has a tendency to do that here. Hole in the wall? Push the piece back and paint over it. Leak in the ceiling and stripping the paint off? Just paint over, don't bother fixing the leak. Sadly they won't let me fix these things myself.

[@mrtemple728]

It’s against the ruling and the heads should be changed legally

[@coolbrotherj]

well of course not, you make them look bad and then people expect them to stop yanking their dicks and do something

[@darkangle16]

Painting the tubes ruin the sprinklers as it acts as a fire barrier and could prevent the sprinklers from going off.

[@currbag]

That's illegal to paint heads. Call your local fire chief he will make the landlord pay to change them

[@CableGuyJoeCCTV]

Many years ago before I retired as a volunteer firefighter we saw the Inception of residential sprinkler a new product on the market came out made of PVC and they're calling it something along CPVC fire-sprinkler systems... it's a fire rated sprinkler that works wonderful in the house about 3000 to $5,000 more in a build .. in a big house it could be a lifesaver also there are the old systems that used to use lead that melted Hutchins fire doors and fire curtains and a garage roll up tight door that would bust the piece of lead, thus eleasing the door or and cause a sprinkler head to go off.. thanks sir always enjoy your videos.... my boys at my work call me Pooh Bear when I'm in my brown Carhartt winter coveralls..

[@darkangle16]

Those pvc pipes are made differently then normal pvc pipes.They are much harder to break and cut .

[@edmundfisher4951]

From earlier experimentation when younger you can't 'pop' them with consumer grade lasers, it reflects most of the light in an interesting pattern (into the perpetrator's eye if you are lucky).

[@linuxthemoon]

Still better than aiming at airplanes!

[@thefishguy8229]

What about my 5 watt blue laser

[@RyanBrooks]

Neat! I always assumed that they were more complicated inside, for some reason. I guess this explains why the sprinklers in my workplace seem to be dripping very slightly... the seals on the plungers are probably getting old.

[@71dembonesTV]

Pete S. Do you know if they were Omega brand heads? I worked at a building where we still had some of them in vacant suites even though the majority got recalled and replaced

[@RusstyGX]

Recalled heads were Made by a company called Central. If you look at them you will see they have a flat Seat where the bulb meets the main body. The recalled heads are Central GB’s. Omegas should still be fine.

[@71dembonesTV]

Tyler Jones The building is in Los Angeles county area, CA. They were definitely Omega brand heads but it was probably a specific model. The recall occurred in the early 2000s from what I can tell. Most of them were replaced then but some got missed and were replaced earlier this year. Unsure what the recall reason was but the ones I saw never leaked. Maybe they didn't activate when they were supposed to?

[@RusstyGX]

@dembones yup that’s the exact reason why. Some of them wouldn’t activate during a fire. It was a national recall but there are still buildings out there with them installed!

[@warphammer]

(Ancient, I know, but important) According to the recall FAQ, this is backwards. GBs are the replacements that were specified, and the Omegas were the recalled heads.

[@misterhat5823]

What is that liquid? It's how the Chinese have figured to export toxic waste for free.

[@cup_and_cone]

For whatever amount of toxic waste China exports, you can be sure there is at least double that amount in their landfills, floating in their rivers or oceans, or just laying in an open field. Truly an ecological nightmare.

[@n-steam]

I assume it's the same stuff they put in non-mercury thermometers, because for both applications you'd want a liquid with the greatest thermal expansion.

[@zee-lusay4087]

That would be alcohol.

[@CurmudgeonExtraordinaire]

You wouldn't want pure water to be in there since it would make quite the mess if it broke from being exposed to freezing temperatures.

[@gordonrichardson2972]

They would contain varying mixtures of ethanol and water for the low-temperature range, and water and glycerine for the high temperature ones. You cannot use a liquid above its boiling point, the thin tube would explode long before it reached the rated temperature.

[@willwitt1020]

The random things people watch at 2 am .

[@SikConVicTioN]

2:23am and I'm watching it 😂

[@mcgregor797]

2:10am.. how did you know?

[@mieleguy1999]

Totally didn't get shit scared when the capsule exploded

[@senatorsmiles]

Man, I just want you to know that during this quarantine I have been binging on your videos. I absolutely love your style of explanation and presentation. I learn a lot from you and I appreciate it!

[@h8GW]

_heats up glass vials_ "Oh it just splattered everywhere. Yes, and hit me in the face, too." -Big Clive, 2017

[@31TimM]

then "I wonder what that liquid is... it looks like blood splatter."

[@simonblaser3365]

I’ve always wondered how they work. This is fascinating.

[@patprop74]

it works almost a principal of the egg, easy to brake from it sides but stronger on its top and bottom . interesting video

[@kevinutting6016]

The glass bulbs used to be made by two German companies, Job and Giesler if I remember correctly. As well as the bubbles, the liquid has metal particles inside to allow the bubble to reappear after they test the bulb in a water tank a couple of degrees below the actuating temperature. At least that’s what I was told when I worked at the sprinkler factory. They also sold a sprinkler production line to China back in the 80’s which I guess eventually put them out of business in the UK.

[@NOBOX7]

very clever of you to spot the bubble size as being the calibration mechanism

[@TheDeankelly]

I remember once working for a company called Tyco some years back assembling these sprinklers. The liquid that those viles contain is a form of Nitroglycerin. When the bubble has fully disappeared, the expansion of the liquid when heated breaks the vile. Thank you for the video, LOVE YOUR STUFF CLIVE. 👍😄

[@TheDeankelly]

@Question Everyfing Viles, not bikes

[@koconnor]

As far as I can remember the sprinkler that points up is not for protection but for use in a dry sprinkler system. They are designed so that the system can be drained fully after activation without leaving pockets of water in the system that could freeze in cold weather.

[@randomisoty422]

I've seen them used in systems where the best place to anchor the pipe was a few feet below the ceiling so they would put the sprinkler on the end of a riser coming up from the feed pipe to be the correct height from the ceiling

[@pibblesnbits]

They used to manufacture mechanical ones with a coil spring that would expand when heated, allowing a valve to open. You should do a review on one of those!

[@RusstyGX]

I️ worked on special hazard fire-sprinkler systems for 7 years as a service tech in the DC Metro area prior to getting hired by the fire department. Its neat to see someone cover this stuff on KZbin. Some of the comments on here make me LOL pretty hard. If you have any questions let me know! Sprinkler systems can be fascinating and some can move a lot of water very fast. Cheers!

[@jamiesuvo7420]

Yes it is the Bubble expansion and size I've been a sprinkler fitter for 30 years my older brother is a sprinkler fitter my two sons my nephews and even one of my sister's boyfriend is a sprinkler fitter now good to see that's some people use in mind to work things out that is intelligence right there

[@ParedCheese]

The "protected" sprinkler seems like a good way of stopping miscreants popping the bulbs with a laser? 🤔 Edit: should have watched to the end of the video, eh? 🙄

[@texasboykc09]

ParedCheese or just the same though process as Clive.

[@timothybarney7257]

I think those covers are more cosmetic than tamper-proof. Instead of having a visually ugly sprinkler head exposed, you just have the flush cover (which can most likely be painted) that's less visually obtrusive showing.

[@timothybarney7257]

Makes sense. I don't have a normal need to be up on NFPA but it makes absolute sense.

[@stanpatterson5033]

@Pete S. - does anyone know exactly just how many colors ARE under the sun?

[@zee-lusay4087]

all of them.

[@HerraHidalgo]

In Finland we have sprinklers in every new office building. We also have a tendency to put saunas into the top floors of office buildings adjacent to the top executive conference rooms. And it is a tradition for the builders’ bosses and top client executives to have the first sauna session in a new building… In the seventies a foreign architect designed the first really tall office building in finland and put sprinklers in every room… including the sauna. The sauna was filled with the cream of Finnish oil industry and politicians when the sprinlers went off and sprayed hot, murky water all over the hot room.

[@Bigrignohio]

Please tell me you were wearing safety glasses! Now why not light one up with a LED. There are residential sprinkler systems that use PEX tubing. They are plumbed in with the regular plumbing (often the toilet) so you do not have to regularly flush them out. The diverter plates are shaped for the spread pattern. You can get close-to-wall 180 degree patterns, side wall emitters, etc.

[@bigclivedotcom]

+Bigrignohio I'm always wearing glasses for at least some protection.

[@Bigrignohio]

I knew you wore glasses. However I am constantly surprised by how many consider standard glasses to be sufficient protection. Still some protection is better than no protection. I am just as guilty of that feeling. Which now is so much worse because I had vision correction surgery and sometimes forget to wear goggles when I should.

[@ERIFNOMI]

Engage safety squints.

[@twocvbloke]

Regular glasses are indeed inadequate for eye protection, I know this only too well when I was grinding a metal part down, and a fragment of hot metal flew off and went almost dead-centre in my right eye, and stuck to the cornea, was fun extracting that, but left my eye a bit useless for a week before it started to heal up and clear, I got lucky though, others may not be so lucky...

[@cheerfultrout4381]

I was wondering if this sort of tie in was possible, thanks.

[@jtveg]

A sprinkler as a manly necklace 📿 What an awesome idea. 👍🏻 Thanks so much for sharing. 😎👌🏻

[@alf3488]

7:07 “oh! It splattered everywhere.” I’m weak.

[@aplusjimages]

To answer your question about the high heat systems, we use them in the film industry for sets. Since we have all those high heat lights in the ceiling we need a fire suppression system that won't go off when we turn the lights on.

[@wickieworld]

Try the Duluth Trading Company for overalls. They appear to ship to the UK. Their products are super durable.

[@terrydavis3620]

Old post but just stumbled across this. Love yer vids Clive. I design these systems for a living. The heads themselves can withstand more but the typical system working pressure is 175psi. Installed systems are tested at 200psi or 50psi above the expected working pressure before being placed in service. Each manufacturer makes 1200+ different variations. Into which they have invested millions of dollars in testing. Subtle deflector changes dramatically effect performance. Choosing a sprinkler for a specific application requires some experience. All sprinklers have to be proven and then listed by Underwriter Laboratories to be used in a system here in the states. The Chinese Ebay variants are likely not UL listed. A properly designed sprinkler system is proven hydraulically based on the available water supply. The pipe sizing is dictated by this math. This math in effect simulates a fire condition and proves how the system will perform in that scenario. There are minimum application densities needed for a given/expected fire load. Also, a system for your home has a different set of parameters than a commercial building.

[@anameorsomething7241]

My dumbass thought the title meant sprinklers that shot fire instead of water. 😂

[@bigclivedotcom]

It would be "interesting" if the sprinkler system was pressurised with gasoline.

[@carolynmmitchell2240]

bigclivedotcom I would love to see that

[@edb8120]

In most of the US you can put sprinklers in you home for an exit route (not the whole house) using plastic supply pipe. After all it only needs to give you 90 sec to get out in case of fire. The little rubber seal is a big deal. A few years back one of the largest producers of these heads was required to recall millions of these because the rubber was corroding the metal and then the head would not release properly. They simply filed for liquidation.

[@paulgascoigne5343]

You might not want them running off mains water supply incase the pressure is too high or you get water thumping from other equipment which utilises it, it wouldn't be pretty if they all went off because there was a sudden surge. If I remember rightly they often have a drenching tank/cistern somewhere in the building which is fed by mains water and topped up. That also helps incase the water supply is interrupted at some point.

[@timothybarney7257]

Cisterns/tanks would most likely be utilized in high-rise construction since water pressure drops the higher you go unless you pump it up to an even higher level and allow it to flow back down under gravity. That's why so many buildings in NYC have water tanks on the roof. And depending on whether the sprinkler installation is wet or dry, the supply is either mains pressure backed up in many cases by a dedicated "fire" pump (wet) or fed from an outside sprinkler connection that the fire department connects their pumper to to supply high pressure water (dry).

[@matthewkriebel7342]

Water hammering isn't a big problem. Reserve tanks are used when the municipal water supply cannot deliver the flow needed, such as more rural and well-fed water supplies. Low- and mid-rise buildings often have high-pressure water supply separate from domestic, like how hydrants are fed.

[@bisrosolan]

I worked at Viking Corp, a manufacturer of sprinkler system. Upstream of the heads is usually a pressure regulator. Also, dry systems don't require a detector. It's all done mechanically.

[@jaredd9297]

Sprinkler equipment is tested to 300 psi you need a really big surge to set a head off. Your plumbing devices are only rated for 120 give or take.

[@throttlebottle5906]

sprinkler heads are rated 175PSI working, special 250PSI high pressure are available. they're probably tested to 500PSI for the 175 working and higher for 250PSI

[@ArcAiN6]

The liquid within the ampule of the sprinkler head is a mixture of alcohol and water or glycerin and water. The % of each is changed to determine the activation temperature of the head. The color is from a dye and indicates the activation temperature. It is put in the liquid so that you can visually inspect the ampule to make sure it is still intact and the liquid has not evaporated or drained out without climbing up to the head to look. This is most often caused by the glass of the ampule cracking and the liquid evaporating. This would cause the head to go off at other than the stated activation temperature (either lower or higher depending upon the type of fracture of the glass). As previously stated, the heating of the liquid creates an internal pressure within the ampule which breaks the glass at the activation temp. Low melting metal alloys such as woods metal are also used. Common temp ranges, based on maximum ceiling temperature are: 135-170 deg F, 175-225 deg F, 250-300 deg F, 325-375 deg F, 400-475 deg F, 500-575 deg F and 650 deg F. The faster the element is heated up the lower within the range it will activate.

[@NightOfTheLiving8bit]

Wow, it's crazy thinking that I was one of Clives first 1,000 subs...and here he is, at 300k now! Yikes!

[@bigclivedotcom]

It's crazy for me too.

[@K-Riz314]

Likewise! 583k now!

[@Thermalions]

Big Clive, the king of understated segues.

[@KyrosX27]

Suggested to me by KZbin. Huh. Knowledge I never knew I needed or was interested at. Thanks!

[@jkobain]

I read the title, watch the preview and I understand that it can be explained in a couple of short sentences. But I love videos from Big Clive, so I watch it. Thank you!

[@notarookee778]

In the early 70's I was working in what was laughingly referred to as a "light psychiatric facility" which translates into "mostly harmless loony tunes ". One night at 0-dark-thirty one of the loons set off a fire sprinkler in the linen closet. They were allowed to smoke back then and he decided the closet was a good place to throw his still glowing butt. Chaotic pandemonium ensued as crazy folks don't like loud bells ringing and have no concept of evacuation when awakened from a Thorazine induced slumber. Soon the fire department arrived the fire was out but the one sprinkler had dumped inches of water that covered an entire wing of the building. Grandview Sanitorium was a very interesting place.

[@AdhamOhm]

All these years, I never knew that the color of the vial fluid indicated its break temperature. I just thought it varied by manufacturer. You learn something new every day.

[@Doramius]

Someone may have already covered this in the comments, but you'll commonly see the green, blue & violet ones in high temp areas. Many Restaurants have the green and blue ones near the oven hoods. It would really cause issues if the cook set one off lunch or dinner service. ;)

[@MrAsBBB]

And that necklace! Will make you an absolute fortune!

[@nolanf7023]

Episode 28 Why am I watching this

[@tallman11282]

Last year a co-worker hit a sprinkler head in some racking with a forklift. By the time the valves were closed half the aisles of the warehouse area had standing water. Took hours to get all the water cleaned up. Miraculously no products were damaged.

[@ericcarabetta1161]

134.6 °F 154.4 °F 174.2 °F 199.4 °F 285.8 °F 359.6 °F

[@mat2941]

Eric Carabetta lol

[@Anvilshock]

Those numbers mean nothing to me ...

[@samuelruiz7377]

Mr.Noodle _ thanks for the freedom translation

[@synchronizeddissonance6243]

Weak.

[@gamingcujo9443]

I was confused by this comment til I realized dude was translating temperatures for the Mericans lol

[@niiidar]

Saunas around here have blue-colored ampules. I have long wondered why, but this explains it. Thanks!

[@nighthawk7x203]

I'm officially scared of google, due to the fact I was thinking about this the other day, never said a single word about it though. It was pure thought... This still pops up on my recommendations.

[@oracla]

I like the odd funny thing that you say, but the splatter moment was just hilarious. Really LOLd.

[@johnsammut8540]

Hmmm the colours almost replicate part of the resistor colour code.......

[@KallePihlajasaari]

Yeah, almost rainbow with the red and orange not well separated.

[@Robothut]

I would think water and glycerin or glycol, but not alcohol, you don't want to feed the fire. Very interesting video Clive, the bubble control never entered my mind. Thank you.

[@GigsVT]

Robothut A fire large enough to set a sprinkler isnt going to care either way about 2ml of alcohol. They dont go off on small fires.

[@bigclivedotcom]

The quantity is tiny, and would promptly be followed by gallons of water.

[@Robothut]

Yes I understand that fact, but you have to understand the way LAW makers think, the guys that set the rules are not logical like us. You are right it would not make any difference, I agree but I also do not think that the device would be allowed to be made with Alcohol in it. Great topic !

[@MicraHakkinen]

4:35 "There must be an alloy that melts" Could be, or maybe it's even simpler than that. I'd imagine a fire would heat up the inside of the little canister quickly enough for the sprinkler to simply go off and then the water pressure popping off the lid.

[@davidhoekje7842]

The hole that the plug is covering varies by the volume of water that's desired to be delivered, and they're also available with various patterns of spray beyond a circle. If a building or building area is heavily involved in fire then the fire department can deliver water at a very high pressure and blow out all of the heads in that zone. The dry standpipes on the outside of buildings allow the fire department to deliver water at higher volumes and higher pressures than the municipal line the building is typically otherwise connected to. It's common in the states to install over near the furnace connected to the house water piping. In freezing climates the system is full of air holding the water at bay so that they don't freeze and break.

[@TheScott10012]

What happened to clive's left thumbnail?

[@AestheticFunk]

TheScott10012 Our Uncle Clive is a working man. He most likely hammered his nail or had something dropped on it.

[@TheScott10012]

Yeah, that's probably the case. Just wondered if he had mentioned it in one of his videos and I missed it.

[@silberwolfy]

It was a work shop accdent it was messing around with something spring loaded and a went bang on his nail he said it about 4 or 5 vids back

[@McScrubington]

He explains what happen to his nail in his "Lithuanian MRE" video, at around 2:30. kzbin.info/www/bejne/b4S8YqqXqLJ0nsU

[@BradpTMO]

McScrubington thanks, I was wonder about that as well.

[@ifell3]

I always thought they were triggered by the alarm system. Nice one Clive

[@RobertBeck-pp2ru]

Yet another wonderful dissection by Clive. Just a note: These are not intended to "put out" the fire. Their purpose is to spray cooling water over a wide area to help absorb heat from the fire long enough to give the fire department time to get into position at the scene. The firemen put out the fire, which hopefully is not yet out of control. And I do have them piped near the ceiling in my shop building where I do welding jobs on my projects, along with a very loud siren. Cheap extra insurance.

[@bigclivedotcom]

It's notable that many fires in buildings with sprinklers are actually out before the fire brigade arrive.

[@ApolloTheDerg]

My first week at my previous job we where mopping the ceilings and my co worker who started when I did hit one. That was a fun day.

[@RedFathom]

the bubble is probably nothing. they are probably heated to their trip temperature then sealed. the bubble would form as the liquid shrank in volume creating a vacuum, or vapor bubble.

[@superdau]

That would make sense and sounds really easy to accurately control. I wouldn't know how they could otherwise put the exact amount of air/gas into the tube when every tube will seal slightly differently.

[@cheerfultrout4381]

If you think about it though, if the bubble is being formed as a by-product of a process like that, the size of the bubble should be fairly consistent each time and you could actually use it for quality control purposes.

[@agvulpine]

I expect earlier alcohol vials have been replaced with bubble-containing water vials, to cut production costs by millions of dollars. Same reason that bismuth tabs were replaced with alcohol vials in the first place.

[@breid1102]

Air can be compressed however liquid can not so the bigger the bubble the more heat is required to hit a high enough pressure IE explode . You will find the only difference with the liquid is the coloring being used to indicate temps however the higher temp units will have a larger bubble this offers more room for the liquid to expand before it hits the popping point.

[@RedFathom]

air would add a level of error in the accuracy of the temperature sensing, but a void or vacuum knowing the expansion rate will give you the exact temperature it will rupture at.

[@maicod]

that glass and red spatter is a neat way to prepare for halloween ;-)

[@MrStevieDLFC]

I always taught they had like a wax that melted to set them off

[@mcgyver272000]

Older sprinklers had a fusible link that released the plug. I don't think wax was used since it softened so close to room temperature.

[@rmd2387]

These are part of a wet sprinkler system, which is essentially using the sprinkler as a valve per source. There are dry systems where there is no water in the plumbing and it’s typically held in a reservoir until an alarm is tripped so that series of sprinklers can be activated, ie in grids, rooms or sections. Each system has an appropriate application. In our fire company we also carry sprinkler plugs that are wedge shaped devices with rubber plugs on the sides so that it blocks the water flow on an activated sprinkler.

[@rmd2387]

I should also mention that the dry system sprinklers have no vials, they’re simply open so they can flood a compartment or wide area at once.

[@newjerseybill3521]

Not sure I would trust Chinese quality and tolerances for a life safety appliance. :(

[@Wackyscfm]

You are correct, the liquid is alcohol. The hidden or recessed sprinklers cover plate is just held on with a low heat solder and little bubble is for the expansion and determines the temperature that the tubes will shatter.

[@mattypants]

The liquid inside is glycerin, which expands as it heats up and you are correct, the flush mount caps are soldered on with solder that has a melting temperature about 10% lower than the burst temperature of the glass vile. This way they fall off right before the vile pops.

[@BritishBoy1971]

I've often wondered about how sprinkler heads work etc. Thanks for showing us Clive!! 🙂

[@thebearsblog8386]

The force of water is what kicks the flush mount cap. Most systems are at 75psi.

[@StRoRo]

Such a simple device and works so well

[@n00bhotline]

I love these videos where you take a fairly in depth look at a simple or ubiquitous technology!

[@NobodyWhatsoever]

You should do a macro slow-motion video of one of the higher temperature tubes, to watch what happens internally. It will most likely be unremarkable, but it may be interesting. Will the changing pressure cause the bubble to shrink? Will it shrink enough to sink the bubble?

[@arcanekand]

The liquid within the ampule of the sprinkler head is a mixture of alcohol and water or glycerin and water. The % of each is changed to determine the activation temperature of the head. The color is from a dye and indicates the activation temperature. It is put in the liquid so that you can visually inspect the ampule to make sure it is still intact and the liquid has not evaporated or drained out without climbing up to the head to look. This is most often caused by the glass of the ampule cracking and the liquid evaporating. This would cause the head to go off at other than the stated activation temperature (either lower or higher depending upon the type of fracture of the glass).

[@LarsSveen]

Fascinating as always, Clive.

[@StreuB1]

Living in Northern Illinois, I grew up with and love my Carhartts. Might I suggest also the Carhartt style #100632 zipper front hooded sweatshirt with the rutland thermal (waffle weave) inner liner? I am a big guy, 6'4" tall, 255lbs, and as such, carry a lot of body temperature around. Likely you have the same problem? Because of this, I don't wear heavy coats until the temperature really drops (or there is a lot of wind and I need a wind break). This sweatshirt is my most worn item once it gets chilly out because it breathes, its very warm, its thick but its loose fitting and has the Carhartt cut for working guys n gals so it moves well with you. Mine is chocked full of cuts and holes from working and welding but its still the most comfy thing I own. I highly recommend it. The 3-season midweight style 100631 is also stellar!

[@ThomasWinders]

Generally speaking: the smaller the bubble, the higher the pressure inside the vial... thus, it should break earlier (=at lower temperatures).

[@madbstard1]

Very interesting as usual. Watched the explosion a few times at slower speeds and it looks so cool!

[@jamesvalentine925]

Thank you bigclivedotcom, today I wen't into pound land while out shopping with the other half. I wondered around and was overwhelmingly attracted to USB power banks and mini torches. I ended up buying a couple of bits which I will take apart and inspect.

[@kuhrd]

From what I recall the liquid is simply alcohol with a dye to make the sprinkler vile the correct color for the rating. It really is as simple as bubble size to adjust the temperature that they go off since the liquid only has so much room to expand before it shifts from pneumatic to hydraulic pressure levels and the vile ruptures.

[@gordonrichardson2972]

Thanks for the reminder about the terminology! I would assume that varying the amount of water mixed with ethanol and glycerine would change the vapour pressure curve versus temperature. Does the bubble contain normal air, or a partial vacuum? Either method would work IMO.

[@bigbadjohn10]

The small ceiling cans with covers are good for hotels, restaurants and homes as they make the heads less obvious.

[@EnriquePage]

As always, great video Clive! Could you please test the covered version? Do you think you heat gun will be enough to trigger it?

[@mariuslambacher8743]

Regarding your comment on filling those glas tubes using a vacuum: that would also be an easy way to quite precisely control the size of the air bubble! The lower the residual pressure in the tube is, the less remaining gasses are in there -> the smaller the air bubble becomes; the higher the pressure is, the bubble becomes larger. This only my speculation though!

[@thephantom1492]

Also, those point up allow for easy drying of the pipe. Many sprinkler system are actually dry, that's it, they are filled with air. There is a valve that prevent water from going in when there is some air pressure on the other side, I beleive it require 1/5 of the water pressure to keep the valve closed. A compressor is used to keep the system pressurised with air. This is done where the pipes are expected to be exposed to freezing condition, like a non-heated warehouse. So, the sprinkler head open, air rush out. The compressor try to keep the pressure, but since the airflow is very restricted (on purpose of course, they add a flow restrictor for the air) the pressure quickly drop. Once the pressure dropped enought the water valve open and flood the pipe with city pressure. A pressure sensor there detect that the valve has been opened and turn on a pump, which boost the pressure to quite more than what the city can provide. The city pressure I beleive is about 40-60psi, and the air pressure about 15-20psi, the water pump can do 150psi or more. The air DOES slow down the reaction time, but this is better than a frozen pipe and no water at all. Also, a sprinkler system is NOT mean to extinguish the fire, it is designed to slow down or stop the propagation of the fire. Since the fire can't propagate more than very slowly, it leave plently of time for the firefighters to actually do their job. A sprinkler system to extinguish the fire would require just too much water, and you can't extinguish a fire that burn under something (covered), like for example a trash can burning under a desk. However, in such case, the fire won't propagate to the next cubicle, and may actually die by itself once everything it can burn did burned. But again, this is not the effect of the sprinker itself, it just prevented the fire from having more thing to burn, and just let it consume itself.

[@ChoppingtonOtter]

Fascinating! I remember first ever seeing these in Woolworths when I was a kid in the early 70s and being been curious about them.

[@Legion563]

One of the most stressful jobs I have had recently was cleaning around these in a school after it was damaged by flooding. Sat 30ft+ in some scaffolding cleaning the rafters with sprinkler heads everywhere. One slip up and you have flooded the school all over again :/

[@RODALCO2007]

Great video Clive, didn't know that the bubble caused the triggering point. I knew about the different colours and temperatures.

[@bigclivedotcom]

I didn't know about the bubble bit myself until I spotted the graduated bubbles in the different coloured vials. When I heated it the bubble gradually reduced in size as it was compressed by the expanding liquid, and it was only when it disappeared completely that the vial burst.

[@therealCG62]

I'd wager the flatter diffuser is for getting a better horizontal spread of water, i.e. in a sprinklerhead placed inside warehouse racking with flammable materials in it. We have a setup like that where I work (I'll have to check and see what shape the diffusers are tomorrow) to douse aerosol cans if they vials pop.

[@paulmaxwell8851]

I'm in central British Columbia, Canada. I installed sprinklers in my super-insulated off-grid home, using Pex tubing runs over a 5/8 inch firestop drywall ceiling. Contrary to popular belief Pex IS suitable for residential sprinkler systems. I'm seriously considering converting to a dry system so I can add exterior sprinklers.

[@bigclivedotcom]

Interesting. The behaviour of PEX would be interesting in a fire as the flow of water to a ruptured sprinkler would theoretically cool the PEX and stop it rupturing. But if it did it would rupture in the area of greatest heat and that would be where the water was needed.

[@RenThraysk]

There's a few Carhartt WIP stores in the UK, but they seem to be catering to people that would have difficulty changing a light bulb.

[@bigclivedotcom]

Sadly it is a fashion thing here. I wonder if they make special flimsy trousers for them that won't chafe their delicate legs.

[@CurmudgeonExtraordinaire]

If I was headed over to the UK again anytime soon, I would offer to let you ship them to me and I could bring them over with my normal luggage, my next trip over there isn't until around August of next year, IIRC.

[@lawrencegenereux8567]

Another method by which these function is to hold the water pressure back with a plug of an indium/bismuth alloy that is blended to melt at the desired temperature. This is also used in self-closing fire doors, where the doors are held open by a two-piece chain held together by a slug of indium/bismuth alloy.

[@tylerpeterson4726]

You proposed a vacuum to get rid of the air. If you know the volume of the vial, you can calculate the number of gas particles in the vial at an given pressure. Then you use that number to figure out how big the bubble will be if you submerge the bulb in liquid and return the pressure to atmospheric pressure. This is just a guess as to how it works, but I think it’s plausible.

[@bigbadjohn10]

I think the covers would be good in places like hotels and high end offices etc. I suspect that the liquid would need to have some resistance to freezing as some locations are likely to be cold. Temperatures at ceiling level rise very quickly to above these temperatures with even a modest fire, but it would be important to prevent false firing in environments where hot processes are undertaken e.g. Furnaces, kilns etc.

[@swallin19]

I remember a story from Val Guest, the film director, who first met the Crazy Gang in 1937, they were all standing in the film studio, staring at a sprinkler on the ceiling. Bud Flanagan said shush, they were doing a sweepstake on when it would go off, as they had lit a fire in the storage room next door....nearest took the pot

[@joelwatts9042]

If you mounted an led where the glass vial was, would make a cool lamp. Maybe several on different arms each projecting the diverter pattern on the walls and ceiling.

[@thebigirishpotato]

You should show us your bench worktop in a video sometime. Would be cool to see what the worktop looks like.

[@bigclivedotcom]

It's basically a huge mess of technical stuff piled high.

[@volvomad]

Clive - the very slack threads on that enclosure appear to allow the water pressure to blow the cover off.

[@AlaaIssa]

In the one with the white cap, i don't think there's any sort of alloy that melts or anything like that. Simply when the vile is heated it breaks allowing the water flow to push the deflector which in turn pushes the cap off. The cap contact-points with the base must be easily breakable i'm guessing. I'm also guessing is that the lowest temperature rated capsule is used in this sprinkler since the metal base and white cover would deflect some, if not most, of the heat away.

[@35manning]

A quick run down on the most common setup in Australia for sprinklers. We almost exclusively use a wet system as we don't have issues with pipes freezing. The sprinklers supply starts at the mains, runs past a one way valve and a supply cut off valve. The pipe here has multiple outlets and an inlet which I'll explain in a minute, but then runs off to the sprinkler heads and finally at the end is a drain valve. The aforementioned connections consist of an outlet to an electronic pressure sensor, a water flow based mechanical klaxon alarm and a pressure boost pump. There's also a number of pressure gauges and shut off valves and one way valves to the different components. The mains pressure (300 - 800 kpa depending on the area) is boosted up to a higher pressure, (800 - 1,500 kpa). If a sprinkler head activates, the system pressure drops to the mains pressure which is used to activate the electronic alarm and evacuation public address systems etc. Depending on the building, the sprinkler may be have a booster point. This is basically a fire hydrant from the mains and an input connection after the one way valve. We can park a fire truck at that point, take water from the mains and increase the pressure with the trucks pump and feed that back into the sprinkler system. Many buildings fitter with sprinklers also have fire hoses and hydrants inside connected to a separate system of pipes and normally have the booster fittings that connect to the fire trucks. This allows for "ok" fire suppression until firefighters determine what is needed. Our sprinkler heads are not designed to activate via any method other then direct heat. To do so would only reduce the water flow where it's needed and cause water damage where there is no fire. Of course not all systems are the same, even in just one country, but all the systems I've dealt with have been the same in their overall function and only take a few seconds of looking at to identify which pipes / valves are doing what.