[Noisebridge-discuss] Sulfuric Acid

[Sean Cusack]

Sorry one more thing in case peeps are concerned about sulfuric acid vapors
hurting them:

Since I typically work with this stuff in a fume hood, I double checked to
make sure volatility was not really that high. Sure enough, from an MSDS
(different than the one I sent out), the Vapor Pressure was listed as only
<0.001 mmHg @ 25C. Thus at room temp less than 0.001/760 of the air will be
sulfuric acid vapor at any time. The TWA exposure for sulfuric acid as
listed by OSHA (the amount of the fumes you can be exposed to over a fixed
time) is 1mg/m^3 averaged over an hour.

Doing some quick chemi-math:

Assuming ideal gas, i.e. PV=nRT
PV=nRT
(0.001/760 atm) = (n/V)*(0.0821 L*atm/mol*K)*(25+273 K)
n = 5.37*10^-8 mol/L present @ room temp

MW of sulfuric acid = 98.08g/mol = 98.08*1000 mg/mol, therefore:

at room temp, in a sealed system (room with absolutely no airflow), the
fumes from sulfuric acid are at a concentration of _5.27*10^-6 mg/m^3_ which
is about 100,000x less than the exposure limit as set by our government.

In sum, no need to be afraid of getting burned/cancer/whatevs unless you try
really hard to kill yourself by heating this stuff to about 145C. I'll still
put the sign on the door tho so people don't burn the place down on accident
:-D.

Sean


On Sun, Aug 8, 2010 at 8:27 PM, Sean Cusack <sean.p.cusack at gmail.com> wrote:

> Thanks for the feedback all. I'll add a sign to the outside of the darkroom
> warning people that chemicals are in use. I'll set up a wiki page with a
> nburl addy to convey the hazards of anything big as well.
>
> Seth - I don't think we want to go so far as to add a NFPA fire code label.
> The ratings that end up on those labels are *not* standardized. In other
> words, one site's flammability "4" rating may be a different site's "2"
> rating. The person who sets the rating is generally an assigned safety
> person with some kind of qualifications to be making those classifications
> based on their knowledge of the site's storage facilities and level of
> expertise. Since we don't really have one of those people, I don't really
> know who would assign the ratings.
>
> Anyways, I'll get motorin' on a wiki site and a sexy sign for the door.
> Yay!
>
> Sean
>
>
> On Sun, Aug 8, 2010 at 2:13 PM, Kelly <hurtstotouchfire at gmail.com> wrote:
>
>> There are nitrile cloves in the darkroom.
>>
>> On Sun, Aug 8, 2010 at 14:09, Kate McKinley <kate at lugh.net> wrote:
>> > Nitrile gloves are better protection than latex rubber for acids and
>> > various organic solvents, and have the bonus of being usable by people
>> > with latex allergies.
>> >
>> > --
>> > Kate McKinley
>> > kate at lugh.net kate at clp.ly
>> >
>> >
>> >
>> > On Sun, Aug 8, 2010 at 13:16, Sean Cusack <sean.p.cusack at gmail.com>
>> wrote:
>> >> I'll bring some gloves for sure. Its already in a sealed container for
>> >> storage, so it should be cool there. Rameen - I believe its only an
>> irritant
>> >> (so if you step into a vapor of it, it'll burn your eyes and nose like
>> mad).
>> >> Plus, given that the boiling point of the acid is so high, its unlikely
>> that
>> >> you should ever inhale much of it without trying reeeeaaaally hard to
>> do so
>> >> :).
>> >>
>> >> Sean
>> >>
>> >> On Sun, Aug 8, 2010 at 1:02 PM, Rameen <emprameen at gmail.com> wrote:
>> >>>
>> >>> I think it's toxic to inhale. I agree with Sai's suggestions.
>> >>>
>> >>> On Sun, Aug 8, 2010 at 12:33 PM, Sean Cusack <sean.p.cusack at gmail.com
>> >
>> >>> wrote:
>> >>>>
>> >>>> Yo peeps -
>> >>>>
>> >>>> A couple of us darkroomers are attempting to bring up an anodizing
>> line
>> >>>> for some sweet darkroom printing and other awesome Aluminum
>> anodization
>> >>>> needs. Cool, right? The only downside is that the anodizing bath is a
>> 20%
>> >>>> solution of sulfuric acid, thus meaning there is a sulfuric acid bath
>> >>>> sitting in the darkroom.
>> >>>>
>> >>>> This isn't retardedly hazardous or anything (for a hackerspace), but
>> I
>> >>>> wanted to throw this out as a quick FYI on how to clean this up if it
>> ever
>> >>>> happens to spill. If its on the ground thrown some baking soda on it
>> first,
>> >>>> watch it fizz like mad, then pick it up with a paper towel. Be really
>> >>>> careful to not get this stuff on your skin - it will burn like crazy,
>> and
>> >>>> you'll get nasty red burns wherever it hit. If it does happen dump
>> lots and
>> >>>> lots and lots of water on it for 15 minutes. Also, realize that when
>> water
>> >>>> and sulfuric acid meet, a *ton* of heat is generated, so make sure to
>> flush
>> >>>> with cold water.
>> >>>>
>> >>>> Lastly, don't throw mass quantities of this stuff down the drain -
>> it'll
>> >>>> corrode the plumbing pipes and potentially burn right through them.
>> Yay the
>> >>>> power of chemsitry.
>> >>>>
>> >>>> Anyways, this stuff is being stored in the darkroom right now (kinda
>> out
>> >>>> of the way), but given that this is a little more less obvious of a
>> hazard
>> >>>> then a lot of stuff at NB, I thought I'd let everyone know. Questions
>> or
>> >>>> concerns, let me know!
>> >>>>
>> >>>> Sean
>> >>>>
>> >>>> P.S.> Full MSDS is here in case anyone is interested:
>> >>>> http://www.sciencelab.com/msds.php?msdsId=9925146
>> >>>>
>> >>>> _______________________________________________
>> >>>> Noisebridge-discuss mailing list
>> >>>> Noisebridge-discuss at lists.noisebridge.net
>> >>>> https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss
>> >>>>
>> >>>
>> >>
>> >>
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>> >>
>> >>
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>>
>
>
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