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Why the San Francisco Fire Dept manufactures their own wooden ladders (video)
- guynamedloren 16y agoDo they burn...?
- sliverstorm 16y agoIt might seem like a bit of a trollish question, but I'm wondering the same thing. I am trying to think of benefits to wooden ladders; they are heavy, easier to damage, harder to make. Probably an incredible challenge to make extendable ones too. The one upside beyond cosmetics I can think of is they probably don't get hot the way metal does. edit: OK, I finished watching the video, I understand now. So it's not that they are necessarily better than metal, but they are necessary in SF.
- MichaelApproved 16y agoThey are necessary because of the large amount of hanging electrical wires SF has.
- ars 16y agoWhy is it wood vs aluminium? What about fiberglass? Doesn't conduct, lighter, and doesn't fail suddenly in heat.
- britta 16y agoSee the article at http://articles.sfgate.com/2007-06-25/bay-area/17249021_1_wooden-ladders-aluminum-or-fiberglass-san-francisco-s-fire-shop http://articles.sfgate.com/2007-06-25/bay-area/17249021_1_wo... - They don't conduct electricity like aluminum or wet fiberglass ladders do....Aluminum or fiberglass, when it gets too hot, it gets soft; it will actually fold over without any warning."
- msbarnett 16y agoToo light = bad stability in high winds, like those common in San Francisco.
- sliverstorm 16y agodoes aluminum start to conduct at high voltage? Normally the oxide layer makes it a bad conductor.
- Simucal 16y agoThey mentioned in the video that they apply varnish to make them less flammable. So, they do burn but perhaps not as easily as you would think.
- pinaceae 16y agowood is far more safer when exposed to heat than metal. while wood starts to burn on the outside it turns into coal, which effectively seals the remaining wood core from oxygen - preventing (for a while) further structural loss. this is taken into consideration when sizing wooden structures in buildings. metal on the other hand loses structural integrity when exposed to heat shockingly fast. the wtc towers showcased this effect quite publicly. experienced firefighters prefer to deal with fire in wooden structures than in metal ones. they can predict how long a wooden roof structure will take till collapse quite well, while a metal structure is a nightmare. so, flammability and structural integrity under heat are two different things. non-intuitive for most non-engineers, hence the retarded wtc discussions. in SF's case they use wood because of its function as an isolator.
- MichaelApproved 16y ago>>metal on the other hand loses structural integrity when exposed to heat shockingly fast. the wtc towers showcased this effect quite publicly. but isn't that at extremely high temperature? Wouldn't that same amount of heat burn wood far faster than it would damage metal? The wtc towers were exposed to jet fuel and beaten by a jetliner slamming into the building. Also, the metal beams in the wtc towers were made of steel while ladders are made of aluminum.
- evgen 16y agoFor a straight-up failure test, yes. Try exposing wood and metal to fire, then cool it, then expose it again, etc. You can tell visually when the wood is likely to fail much easier than the metal.
- sokoloff 16y agoAluminum (in most alloys) loses significant strength in the 400-500*F range. By 600F, Al alloys are very weak. http://www.burnsstainless.com/yieldstrength.aspx http://www.burnsstainless.com/yieldstrength.aspx
- baguasquirrel 16y ago
- deleted 16y ago[deleted]
- JanezStupar 16y agoLike the other said. If you build it from right type of wood prepared the right way - those things are incredible. They are insulators - helping with electricity AND heat. They are predictable... Wood is an awesome material - but it takes time and expertise to do it right - thus making it expensive. But nevertheless the highest quality and style items are still made of wood - it just ain't cheap. Think: furniture, insulation, windows, doors, floors, stairs... Hell wooden shingle roofs can and do last over hundred years if prepared properly.
- jasonkester 16y agoYikes! Auto-playing video! Kindly put a warning in the title when you post videos. Especially when they a. play automatically b. don't have any actual article accompanying them
- brown9-2 16y agoMy bad. I should have included "(video)" in the title or just linked directly to the video on vimeo.com.
- starpilot 16y agoSFGate article on why they use wood ladders (2007): http://articles.sfgate.com/2007-06-25/bay-area/17249021_1_wooden-ladders-aluminum-or-fiberglass-san-francisco-s-fire-shop http://articles.sfgate.com/2007-06-25/bay-area/17249021_1_wo... They said sales of wooden ladders doubled in the 5 years prior to when the article was written.
- iuguy 16y agoI didn't spot where it said why the SFFD themselves manufacture the ladders (as opposed to buying them from somewhere). Should it really be the job of the SFFD to build ladders from raw materials?
- silvestrov 16y agoI think it's the only method to ensure that all the ladders are of perfect quality. If you outsource the production to the lowest-bidder, then you get lowest-bidder quality. It's a way different thing to build a ladder that your colleagues (and friends) are going to climb, than to build something on an constantly more restrained time schedule for somebody you don't even know the name of. The latter encourages shortcuts, the former encourages avoiding them.
- rdl 16y agoThere are a lot of life safety devices which are made by someone other than an end user, after competitive bidding. You either need to do testing of every article delivered, or set up something like ISO 9000/9001 quality management and accept that you will be paying a premium for a documented, repeatable process. Counterfeit parts getting into the supply chain (which might be visually identical, and may even appear identical to testing) are a problem, but that's where having documented/audited suppliers comes in.
- baguasquirrel 16y agoI don't know how well this is going to be accepted here, but I marveled at the cultural value of making and using your own wooden ladders in this day and age. In our practical, efficiency-obsessed style of doing things, people generally don't care about these details anymore. But those ladders are beautiful. I wished someone had pointed that out, because I'd never noticed it in SF.
- jmtulloss 16y agoBut in a city that can't keep its budget priorities in line, this seems like another instance of a lot of money without any real data that the money produces better results.
- halostatue 16y agoIt's hard to say for sure that you could get a fair assessment since peoples' lives are on the line. If the ladders are twice as much, but due to the peculiar electrical and atmospheric (wind) conditions in SF, could it be argued that these ladders increase the safety of the firefighters? TCO would also have to be measured to be certain that this is worth it or not. If aluminum ladders are half as much, but last a quarter of the time… then it's arguable that the wooden ladders are cheaper.
- baguasquirrel 16y agoI'm close to people who work in the public sector, and this sort of thing is not where the real waste is. This is two or three guys in a shop somewhere. At least they're making stuff. You know that Despair.com catchphrase, "None of us is as dumb as all of us?" Well it's like that. You need some serious mass before you can start moving money and influence. Real waste comes from political graft. Imagine a whole branch of a municipality where more than half the people are managers sitting around and doing nothing. They're all making upwards of 100k, and they're all covering each other's asses. Their propaganda machine is bigger than yours. Now before all you Republicans and Libertarians get all smart-ass, I should add that it happens plenty often in the military-industrial complex too with the contractors who do the majority of the real work. Same stories, different people.
- sbierwagen 16y agoAmazing. An old tradition that has completely failed to change in response to new technology. You wouldn't want to use an aluminum ladder near power lines, of course. So how about fiberglass ladders? After searching on "firefighter fiberglass ladder" you get http://www.fireladder.com/fiberglass.html http://www.fireladder.com/fiberglass.html There's no 50 foot model, like the one talked about in the video, but there's a 40 foot version. Costs half as much, and weighs half as much. It's non-conductive, and most importantly, it's made by a civilian contractor, so you don't have to run your own ladder building shop.
- mrj 16y agoAccording to the video, they prefer the heavier wood because of the high winds in the City.
- parfe 16y agoThe ladder from 1918 was a 65 foot ladder (ladder A-1)
- msbarnett 16y ago> Costs half as much, and weighs half as much. In a high-wind city like San Francisco, being too light is a bug, not a feature.
- bradgessler 16y ago"The San Francisco Fire Department has been "green" since before it was a fad" I fail to see how making your own ladders is "green". Is the carbon footprint of employing two guys that maintain ladders, heating a shop, etc more-so then that of a company that can manufacture ladders at a larger scale? etc? I live across the bay from SF, but if I was a resident of San Francisco, I would seriously consider this an inefficient use of public funds unless they had data to prove that wood ladders are economically superior to fiberglass ladders.
- d2viant 16y agoThey mention that their data actually admits the opposite, that they're less economical, costing about $100/foot. They don't mention what the alternative ladders cost, but it sounds like their argument is because wood ladders gain them advantages that others don't: nonconductive material, heavier weight against winds, etc.
- Retric 16y agoThey also say that they last several times as long. Considering they have a large stock to begin with spending buying a 30' ladder @ 100$ / foot vs 30$ a foot X 3 replacements works out to about the same amount of money. http://www.duosafety.com/price_list.html http://www.duosafety.com/price_list.html
- anthonyb 16y agoAccording to the video they're $100/foot, but last a long time. Update: check starpilot's link here: http://news.ycombinator.com/item?id=1854136 http://news.ycombinator.com/item?id=1854136, which has a lot more information on the reasoning behind the use of wood.
- electromagnetic 16y agoI work on decade old aluminum ladders on a daily basis, I fail to see how wooden ladders last longer under regular conditions. An aluminum ladder conducts electricity, but also conducts heat. I let a ladder on a black shingle roof one day in the middle of summer and I had to get gloves to hold it long enough to literally throw it off the roof. > "You don't want to use a 50-foot lightweight aluminum ladder in heavy winds -- it's too dangerous," Cohane said. Can and do, but fixing the feet and using tie-offs isn't exactly practical for firefighters. > The largest ladder they make is 50 feet, weighs 350 pounds and takes six firefighters to lift. Compare this to the largest ladder we use, which is IIRC 40 feet and is easily moved by one man if done properly (we've had guys fall with them before).
- brudgers 16y agoWood is not just a poor electrical conductor, it's also a poor conductor of heat. That means that a wood ladder resting on a wood building will not become hot enough to ignite the structure on which it is resting.