Reducing outgassing in computer components

[samwales]

A while back, the idea of a site dedicated to people who want to make quiet computers would have seemed crazily niche. But nowadays silentpcreview.com is well-respected and pretty popular.

Yet there is no site for people who want to make computers that outgas less than average. Some people get seriously ill from the fumes from certain PSU's, for example, but are OK with foam fumes. Others are OK with the former, but cannot tolerate formaldehyde, certain foams, new vinyl (either from the vinyl chloride or from byproducts of the manufacture), and so on.

And finally, there is a rapidly growing number of people who just don't want all that stuff in their air, either because it stinks, or because they figure the other 2 categories of people are canaries in the mineshaft -- harbingers of what will happen given that combinations of airborne toxins are minimally tested, or even completely untested, these days.

I created this thread to get ideas on how to build a minimally-toxic computer. All ideas are welcome, from buying used to specific component models and manufacturers that follow RoHS or EPEAT or Greenmark (some of those are just for waste purposes while others actually ban certain flame retardants).

Please keep in the spirit of the thread and make this a safe, friendly place by suggesting practical options. If you are skeptical, create a different thread, rather than posting in this thread. Or simply refrain from posting.

Thanks.

P.S. Examples of wisdom I would like to see in this thread: Seagate 7200.10 750GB HD is RoHS-compliant. Some Gigabyte motherboards are RoHS-compliant. Beware some cases, which use foam. Hard plastics are usually OK unless they are very hot. Soft plastics are worse. Such and such a PC is low power but low toxicity and can be used as a wireless remote X terminal with sound. Flame retardants of such and such a type (e.g. brominated) can be really bad for some people.

 

[firewolfsm]

Wait...you're saying computer exhaust gas into the air? Where does that mass come from?

 

[Biftheunderstudy]

Outgassing is when a solid material releases small amounts of molecules off of it surface, kind of like evaporation, the wiki has a fairly good article on it. The only time I've ever had to worry about it was working with vacuum components. Teflon, stainless steel, ROHS solder (not the flux) are some materials which have good outgassing properties, ie. don't outgas very much. I would think those acrylic cases you can buy would be fairly good.

 

[Stageman]

An interesting and probably important topic in an ever increasingly sensitive to toxins world to discuss, but it would seem to me that beyond a reasonable and rational desire to just have components that were inherently less toxic, the path of least resistance would be to take a newly built system and allow it to burn in and outgas in a ventilated area normally free of people.

 

[samwales]

Still hoping for practical, informed discussion of specific measures to be taken. It is really, really obvious that there are lots of skeptics, so we don't need to be reminded of that. If you are skeptical, please create a different thread, so that this one can be limited to practical, informed discussion.

Burning in a computer is a very good idea and one that some people do. However, many items, including but not limited to items with formaldehyde and vinyl, take *years* to outgas. That is a long time to burn a computer in.

Thanks for mention of ROHS solder. Teflon is tightly bound to its substrate, at least according to an article in _Nature_, but bear in mind that bird owners are told not to use Teflon cookware or else the birds will die. So Teflon outgasses significantly at least with very high heat. Of course, there is little Teflon in computer components AFAIK. But I wanted to mention that in case some people get the wrong idea.

Keep the ideas coming.

 

[firewolfsm]

You could reduce the exhaust airflow. It would make sense that a linear decrease in CFM would also decrease pollutants linearly.

 

[CycloWizard]

1. Preheat oven to 450°.
2. Chop 1 garlic clove, 3 celery stalks.
3. Combine garlic and celery with 2 cups olive oil.
4. Generously coat inside of computer case with sauce.
5. Bake for 4-6 hours or until golden brown and crunchy.

Seriously? Add hexane to the case for an hour, then decant. Dry thoroughly. Add acetone to the case for an hour, then decant. Dry thoroughly. Place case in a kiln for several hours at low heat with forced convection fans. If that doesn't get rid of the low molecular weight volatile compounds, nothing will. Oh, and make sure you do all of the stuff with organic solvents in a fume hood and away from any source of ignition. Seriously.

 

[Adam8281]

This may be so obvious as to be not worth mentioning, but watercooling your components can eliminate all fans but the PSU fan. That's got to cut down on the gas being blown out of the chassis.

 

[samwales]

Obvious ideas in good faith are very welcome also. I assumed that water cooling would be expensive, require special cases, and require more maintenance than fans, otherwise more people would use it. I would be happy to have that assumption be wrong. Have a newegg link for one that you personally like?

 

[Adam8281]

I don't personally watercool, so I don't have a Newegg link for a system I personally like. However, water cooling is not as much of a hassle as you suggest, and for someone who needs to cut down on out gassing, I imagine it might be a worthwhile investment. My sense is that a basic watercooling kit can be had for $250. Frequently, you don't need a special case for watercooling. My Antec P182, which is a pretty mainstream case, has two "portals" in the rear of the case to accommodate water cooling tubes. Re: more maintenance, I think you're probably right that it's "more," but I don't think it's much more. I think you're supposed to change the water like once per year or something.

 

[Cogman]

Originally posted by: Adam8281
I don't personally watercool, so I don't have a Newegg link for a system I personally like. However, water cooling is not as much of a hassle as you suggest, and for someone who needs to cut down on out gassing, I imagine it might be a worthwhile investment. My sense is that a basic watercooling kit can be had for $250. Frequently, you don't need a special case for watercooling. My Antec P182, which is a pretty mainstream case, has two "portals" in the rear of the case to accommodate water cooling tubes. Re: more maintenance, I think you're probably right that it's "more," but I don't think it's much more. I think you're supposed to change the water like once per year or something.

How would that eliminate gases expelled? The gases are produced regaurdless of how many fans you have, the difference is how concentrated it gets in the case. Some time or another it all has to come out anyways.

Not only that, but water cooling is NOT fan less like some believe. You have to cool of the water too you know, this is generally done with a radiator and a fan. Not only that, but you have to add the extra pump equipment which often has soft rubber components for the tubing.

Sorry, but there is no way that will reduce the amount of gas produced, if anything it will increase it (btw I am a skeptic of the whole issue, but as per the OPs request I won't go down that road)

 

[PolymerTim]

I agree with Cogman. The outgassing is occuring frmo the materials regardless of the fans. It would diffuse out of the case even if there were no fan at all.

The only way to reduce outgassing, I believe, is to prevent it at the source of manufacture, as I think you were getting to with all the different standards. Once the stuff is in there, I don't think there is any good way to get it out faster without damaging the equipment. Have you seen what acetone does to most plastics?

I do work in plastics and am generally familiar with the kinds of volatile compounds often found in them. One common type are left over from the polymerization reaction, either residual small molecule (monomer) that never reacted or byproducts of the reaction. Manufacturers often remove most of these, but sometimes enough is left over to be noticeable. Another would be compounds specifically added for their effect on the material properties, most commonly plasticizers. This is what makes vinyl, which is the same plastic as PVC, as soft as leather, and part of the reason it gets harder over the years and eventually cracks.

Materials can usually be made that get the desired properties without the outgassing problem, but they cost more money so it is only natural that companies won't go this route unless their is a financial or legal reason to do so.

Whether or not it is necessary is a difficult question. It takes quite a lot of research to prove that certain low levels of specific chemicals can be harmful over time. For most chemicals, even commonly used ones, we just don't know their effect for sure. I'd like to say better safe than sorry, but you have to draw a line somewhere, make the part, and live your life. So I'm not going to worry about it too much. I probably get far worse fumes in my chemistry lab but I'm sure if enough people wanted less outgassing, it would provide a financial incentive to drive some change.

 

[TuxDave]

Originally posted by: Cogman

Originally posted by: Adam8281
I don't personally watercool, so I don't have a Newegg link for a system I personally like. However, water cooling is not as much of a hassle as you suggest, and for someone who needs to cut down on out gassing, I imagine it might be a worthwhile investment. My sense is that a basic watercooling kit can be had for $250. Frequently, you don't need a special case for watercooling. My Antec P182, which is a pretty mainstream case, has two "portals" in the rear of the case to accommodate water cooling tubes. Re: more maintenance, I think you're probably right that it's "more," but I don't think it's much more. I think you're supposed to change the water like once per year or something.

How would that eliminate gases expelled? The gases are produced regaurdless of how many fans you have, the difference is how concentrated it gets in the case. Some time or another it all has to come out anyways.

Not only that, but water cooling is NOT fan less like some believe. You have to cool of the water too you know, this is generally done with a radiator and a fan. Not only that, but you have to add the extra pump equipment which often has soft rubber components for the tubing.

Sorry, but there is no way that will reduce the amount of gas produced, if anything it will increase it (btw I am a skeptic of the whole issue, but as per the OPs request I won't go down that road)

I'm no expert on outgassing but since someone made an analogy of evaporation vs outgassing, wouldn't the rate of outgassing be affected by some "vapor pressure" equivalent where the gas may be reabsorbed back into the solid? Having a fan move out gas out would bias the solid to keep outgassing and limit the rate of reabsorption.

I'm just guessing that it's probably not a significant factor but this is still the first time I ever heard of outgassing.

 

[PolymerTim]

You've got the right idea, but it is probably not a significant factor in this case since the outgassing (evaporation) is very slow on the timescale of months and years.

You can think of it as a concentration gradient. There is some of the volatile (able to evaporate) compound on the surface and it will slowly evaporate. Then more of teh compound deeper inside the material sees that none remains on te surface and some of it will migrate there in an attempt to bring teh gradient back into balance. As long as the volatile compounds can diffuse through the material and theycontinue to evaporate at the surface, this process will continue, but will slow down as the amount of volatile compound remaining is reduced since this also reduces the gradient which is the driving force.

Since most of these compounds evaporate very slowly, they release very small amounts over very long periods of time. In your compouter case, air is being circulated even if you have no fans due to convection currents. The vapor pressure you mention would only be important if a significant amount of teh volatile compound filled the case of the computer suce that the rate of reabsorption was equal to the rate of outgassing. But since the compounds release so slowly in the first place, I don't believe you would ever get near this point since the rate of air flow, even without fans, would be much faster.

Another area that has me worried about outgassing is a lot of processed wood products. Some of them lately have been shown to put out pretty high levels of things like formaldehyde, at least for the first few days or weeks. This can be especially worriesome when these products are used to make childrens furniture which is wrapped in airtight packaging until it arrives on your doorstep.

 

[silverpig]

Cool your computer to liquid helium temperatures. There's not much that'll outgas at that temperature.

 

[Nathelion]

I suppose the computer-in-a-mini-fridge thing would work for this. Just make sure the seals are tight and that you take the thing outside whenever you want to open it up. And use an old fridge, or the fridge itself is likely to outgas more than the computer would of in the first place.

 

[Paperdoc]

For individuals who react severely to outgassing from electronics, you might consider isolating the major components and providing exhaust to outside the room or building. For example, consider placing the main computer case inside a larger box with air intake slots in the front. Make the front a hinged door that can open for access to buttons, DVD drives. etc. Then put an exhaust fan (maybe similar to one used in a bathroom) in the back of the box (that's where the hot air exits the computer's caes most of the time), with a flex hose that directs the air outside (through a window?), at least into another room with good ventilation, or maybe towards an existing permanent room air exhaust fan.

That would remove most outgasses from the main source from the immediate vicinity of the user. It does not address things like the keyboard and mouse, but since they are small and not hot I would expect them to be less significant sources. That still leaves the display device, a potential big source. You might be able to use the same concept, but I'd guess it would be very inconvenient. On the other hand, I suspect that modern flat-screen displays that operate with little heat generation produce MUCH reduced outgassing compared to the traditional CRT displays.

 

[Adam8281]

Probably a dead end, but since people are mentioning things like liquid helium... I read on Digg the other day about some new, super-expensive, "spray on" compound that will completely waterproof any electronic component (it was advertised towards laptops). When sprayed on, it forms like a 1/100th in. "shell" around the product. I have no idea whether this product is even real, but the concept seems like it might work for outgassing purposes (assuming whatever compound you use isn't itself noxiously volatile - a big assumption). Of course, even if such a product exists and helps with outgassing, you probably wouldn't want to apply it to all of your PC components (I know I'M not "encasing" my MoBo in a spray-on "shell"), but it might work with some of the larger, less sensitive surface areas, like the inside and outside of the case, external surfaces of the PSU, etc.

 

[TuxDave]

Originally posted by: Adam8281
Probably a dead end, but since people are mentioning things like liquid helium... I read on Digg the other day about some new, super-expensive, "spray on" compound that will completely waterproof any electronic component (it was advertised towards laptops). When sprayed on, it forms like a 1/100th in. "shell" around the product. I have no idea whether this product is even real, but the concept seems like it might work for outgassing purposes (assuming whatever compound you use isn't itself noxiously volatile - a big assumption). Of course, even if such a product exists and helps with outgassing, you probably wouldn't want to apply it to all of your PC components (I know I'M not "encasing" my MoBo in a spray-on "shell"), but it might work with some of the larger, less sensitive surface areas, like the inside and outside of the case, external surfaces of the PSU, etc.

Was it this?

http://golden-shellback.com/

That was on ATOT a week or so back.

 

[Adam8281]

No, I don't think it was that, but something similar. Reading the FAQ on the above link, it sounds like that's not a spray on. But the advertisement I read was about a spray-can product, I'm pretty sure. Similar concept, though, I'm sure.

 

[bobsmith1492]

New electronics smell good. I guess it's due to outgassing. *sniff sniff It's like the new-car smell... actually it's probably exactly the same thing.

 

[DrPizza]

Perhaps you could coat the electronics with something that is impermeable to the gases?

 

[CycloWizard]

Originally posted by: DrPizza
Perhaps you could coat the electronics with something that is impermeable to the gases?

Generally, this would also make everything heat up more. Any barrier to diffusion is also a barrier to heat transfer. However, a nicely microstructured surface could minimize that effect.

 

[PolymerTim]

Originally posted by: CycloWizard

Originally posted by: DrPizza
Perhaps you could coat the electronics with something that is impermeable to the gases?

Generally, this would also make everything heat up more. Any barrier to diffusion is also a barrier to heat transfer. However, a nicely microstructured surface could minimize that effect.

That would depend on what diffusion you're trying to prevent. I think there are plenty of ways to block diffusion of small molecules without significantly affecting heat transfer. And actually, I don't believe that most components in a computer producing significant amounts of heat are the ones that are outgassing. Rather it would be various plastic and coated surfaces that just get warm. Any surface that needs significant heat removal would likely not have an organic coating since these tend to reduce thermal transport.

 

[Nathelion]

I think the problem with the coating idea is cost, not feasibility.