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Comment Re:I dunno about LEDs, but CFLs don't last (Score 1) 602

The EPA guidelines are in line with the level of risk: very, very little. If you want to cut your mercury exposure, don't stop using CFLs, stop eating seafood.

As for the Bridges case, you should read the Maine EPA's account. CFLs were new back then, and they had decided to use her case to learn more about what sort of advice they should give for dealing with broken bulbs. So they sent someone with a meter because they wanted to learn more, not because that's standard practice. The carpet was already intended for removal as part of a rennovation. They took readings all over the room. The only place with "high" levels was right where the bulb broke - not in the ambient air, not anywhere else on the carpet, not on the toys, not even under the carpet where it broke. I say "high" because even the levels right where it broke weren't actually high, just over Maine's long-term exposure guidelines (which is obviously not applicable to a temporary event). Moving the meter even six to eight inches away rom the breakage point dropped the levels way down. She was told that the bulb breakage was "of negligible health concern". However "the homeowner expressed particular nervousness about exposures to mercury even in low numbers", so they told her what she could do if it bothered her, one of which was calling a cleanup contractor. And of course any private cleanup contractor will charge you an utter fortune. The Maine EPA came back two days later after the story hit the news, before anything had been done in the house. The area where the bulb broke had dropped down below Maine's limit.

The case was ridiculously blown out of proportion.

Comment Re:~/.cshrc (Score 1) 208

I've run all of the updates on OS X and I still got the vulnerable message. A couple of days after the bug was public and the patches were available, I grabbed the source from opensource.apple.com, applied the FSF patches (which required some manual intervention, as they didn't apply cleanly) and recompiled. I'm now running a patched bash that isn't vulnerable, but it's not the one that Apple supplied.

Comment Re:I dunno about LEDs, but CFLs don't last (Score 1) 602

My whole family got really fed up very quickly after walking into a dark room, hitting the switch and having to stand there for 5 seconds until the light actually came on

I find this really hard to believe. I've been using CFLs exclusively for over 10 years - mostly buying cheap ones - and I've never seen one that takes more than about half a second to come on. The time taken to get to full brightness I can almost agree with (this was actually why I started using them originally - having a bedside light that took a couple of minutes to get to full brightness was nice) but in recent ones (i.e. ones from the last 4-5 years) the warm-up period has been 5-10 seconds, although growing to about 20 seconds after 3-4 years of use.

Comment Re:I dunno about LEDs, but CFLs don't last (Score 1) 602

Are you reading the same webpage I am? Where does that say you're supposed to bag up your bedding and pillow and toss them into the garbage - "EPA's words"? It says no such thing. It basically says open the windows for 5-10 minutes and shut off your HVAC, scoop up the fragments, use tape to get the little bits, wipe it, put all the waste in a sealed glass jar or plastic bag, and properly dispose of it. Ooooh, terrifying! And at the bottom of the page it says:

What if I can't follow all the recommended steps? or I cleaned up a CFL but didn't do it properly?

Don't be alarmed; these steps are only precautions that reflect best practices for cleaning up a broken CFL. Keep in mind that CFLs contain a very small amount of mercury -- less than 1/100th of the amount in a mercury thermometer.

Clearly you're reading that page from a bizzarro universe where it says something like "If you break a CFL and don't move out of your house and entomb it in a concrete shell then you'll get electro-cancer that will kill you and all of your descendants."

Comment Re:LEDs (Score 1) 602

Link.

I know the guy who runs the company - they're serious about good making good products and being honest with people. Compare with the sort of chinese stuff you see cheaper on Ebay. First off, the stuff you see on Ebay usually lies about the output - they give "nominal watts" instead of actual watts, the nominal watts usually being double that of the actual. And then compare the weight - the Black Dog ones are twice as heavy. Which may not seem like a good thing, but it's because they have such a vastly larger cooling system, which means much greater expected longevity. Also Black Dog goes all out on their spectrum, they use a lot of different bands, including UV.

I'm probably one of the few people in the world using the lights legitimately, lol ;) I grow tropicals in my apartment in Iceland.

Comment Re:China won't like this (Score 1) 69

Or perhaps I'm misunderstanding you - are you saying that there's something extraordinary about the concept of thermal spraying to lay down material? Perhaps you should look it up. Usually it's only used for high performance coatings, but there's no reason that with computer control you couldn't lay down whole objects, rate is (mainly) only limited by nozzle size, so you can trade off between speed and precision.

Comment Re:China won't like this (Score 1) 69

What "extraordinary claim" is being made?

What praytell is so unreasonable about discussing technological possibilities? Is this not Slashdot? If there's something ridiculous about technological speculations on something that they do not currently have the time or resources to work more on, then almost all all of modern technology was at some point ridiculous.

Why exactly do you think that 3d printers must inherently always be glorified hot glue guns? Wht is so unreasonable about the concept that there could be alternative methods to lay down material in alternative shapes?

Comment Re:China won't like this (Score 1) 69

And a home injection moulder is impossible why? Bed of pistons on one side (doesn't' need to be high res), attached to a stretchy surface (even a high temperature stretchy surface if you need one - graphite felt can tolerate most molten metals). Exact same thing on the other side. Thus they can make a mold shaped like any object. Your system can spray release agent or whatever else is needed. Hollows can be made either by inflation of an air bag inside the mold; casting and releasing an inner, re-applying release agent, then recasting; or a combination of the two. If the bed of the moulder was openable, you could use the mould as a layup for composites.

I think people's conceptions of the potential of garage/small business solid printing is way too constrained, people envisioning only half-arsed extruders. Personally I'd love to see an attempt to 3d print with thermal spraying; your material could be anything you can have as a sufficiently fine power or fibers, and you can have it impact the target at whatever temperature (cold to thousands of degree) and speed (slow to over 1000 m/s) you want, depending on the type of material, by varying the partial pressures of the fuel and air you feed into the chamber. You have the potential to print out materials that are even stronger than cast objects (high velocity compaction). You can use the same system to do finishing work (finishing the main purpose of thermal spraying today) - sanding, polishing, coating, painting, etc. It could build support structures and then later sandblast them away. The potential seems tremendous. Not super fast (although you can vary your nozzle size, bigger for greater flow rate at the cost of less precision), but still, I find the concept very interesting.

Comment Re:LEDs (Score 1) 602

All of my lights in my apartment are either fluorescent or LED, mainly LED, yet I still consume about 2k kilowatt hours per month / 65 kWh per day / 2.7 kW average.

Hmm, I should probably mention that my brightest LED light is 570 watts (real consumption, not incandescent equivalent) and is on 24/7 ;)

Comment Re:I dunno about LEDs, but CFLs don't last (Score 3, Informative) 602

Where's your controlled, statistically significant comparative study data? Or are we supposed to go on an anecdote? Because we do have lots of data - for example, here Consumer Reports talks about their testing results.

Mercury? Every bulb CF tested contained less than 5mg. Let's go with 4mg as our figure (even though some are under 2%). 17-44% of said mercury will vaporize if you leave it sitting around for 8 hours. Let's say you clean it up and 10% gets into your air, which is probably a gross overestimate. What percent of that will you breathe and have actually get incorporated into your body? Probably in the low single digits, but lets be pessimistic and say 20%. So 80 micrograms. The mercury of a mere 1 1/2 cans of tuna.

But wait, there's more. The mercury in CFLs is "inorganic" (metallic, unbound) mercury, while mercury found in food is almost exclusively "organic" (methyl and dimethyl mercury). "Organic" mercury, being much more bioavailable, has many times worse health consequences per microgram.

The short of it? Don't stand in a closet and smash dozens of CFLs and then fan them while hovering over them and breathing deeply for a day or so. Otherwise, you're fine.

Comment Re:I dunno about LEDs, but CFLs don't last (Score 3, Insightful) 602

Let's do it again. The last set of CFLs I bought cost 50p each (the ones before that were 30p, but that was a special offer). According to my electricity bill, I pay a tiny fraction of a penny under 15p/kWh. That means that the bulb costs slightly more than 3kWh of electricity. It's a 15W bulb replacing a 60W one, so that's a 45W saving. Assuming that the incandescent is free, then it takes 75 hours of operation for it to save money. At 3 hours a day, that's 25 days. When I first did the arithmetic, the CFLs were 3-4 times more expensive, so it worked out at 3 months.

This is why I find the resistance to CFLs so hard to understand. It's saved me quite a bit of money over the last decade.

Comment Re:I dunno about LEDs, but CFLs don't last (Score 1) 602

If you save more on energy, but spend a lot more on replacement bulbs, what is the break even point before it was a good investment?

When I did the arithmetic quite a few years ago, the break even point for CFLs was about 3 months. The bulbs I bought back then all lasted 6+ years. The cost of a CFL is around the cost of 3-10kWh, depending on the brand, so even if they incandescents were free you don't need the CFLs to last very long to break even.

Comment Re:I dunno about LEDs, but CFLs don't last (Score 3, Interesting) 602

Sounds like something's wrong with your wiring. I switched to using CFLs over a decade ago and the shortest lifetime I've had on one is 6 years (I think - one might have gone after 4). The first time I moved house, I brought a load with me, but they'd become so cheap that I didn't bother the last time. The only incandescents I've had last longer than a year are ones that are rarely used. I worked out that - back when they were expensive - that after 3 months of operation they'd saved me more in electricity than the cost of an equivalent incandescent, so they've been a pretty good investment.

Comment Re:I dunno about LEDs, but CFLs don't last (Score 1) 602

I don't know why that's a surprise for you. Incandescents are also limited in terms of lifetime by being turned on and off. The thermal shock of taking a very thin wire filament from room temperature up to white hot in a fraction of a second is not very good for its lifetime. That's why lightbulbs are most likely to break when you turn them on.

Comment Re:Oh good (Score 2) 907

Ignoring how easy a device should be to disable. Even if it's not simple to physically disconnect the device for some reason, imagine how easy it'd be to clip the antenna or shield it whatnot. No signal, no disabling. What are they going to do, send a repo man after the car? Well, then the device was useless because that's what they'd have done anyway.

Plus, given that I bet a lot of people with such devices live in bad neighborhoods, I bet there's no shortage of people in the area who could offer hotwiring services for a lot cheaper than a late car payment ;)

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