Chemical safety (was: Re: [Noisebridge-discuss] darkroom at the noisebridge space)

[Mark Cohen]

Hi Jim,

Indeed you can reclaim the silver. I've worked in many labs that had a  
machine to do it. We used Electrolytic devices, but there are a few  
ways to do it.

Kodak has a page of vendors that sell the equipment :

http://www.kodak.com/eknec/PageQuerier.jhtml?pq-path=4234&pq-locale=en_US

Once the flake is recovered, it needs to be refined.

-Mark



On Oct 3, 2008, at 6:00 PM, jim wrote:

>
>   is there a way to reclaim the silver?
> i'm interested in silver plating.
>
>
> On Fri, 2008-10-03 at 14:13 -0700, Mark Cohen wrote:
>> Comments in line :
>>
>> On Oct 3, 2008, at 1:00 PM, Seth David Schoen wrote:
>>
>>> Audrey Penven writes:
>>>
>>>> We'll need to figure out the details of each chemical process that
>>>> will happen in the space.  I imagine that some of them will be
>>>> compatible, use the same chemicals, and otherwise coexist nicely.
>>>> Some of them, not so much.  We can make sure to have a bunch of  
>>>> trays
>>>> on hand, labeled with the chemical bath they can hold.
>>>>
>>>> As far as disposal goes - regular developer and stop baths can be
>>>> mixed together and poured down the drain safely.  Fixer needs more
>>>> care.  I believe that Rayko takes used fixer and recycles it for a
>>>> fee.  I'll find out the details of this.
>>>
>>> This reminds me of safety questions that I had about both the  
>>> darkroom
>>> and chemistry lab.  I guess that the same safety questions apply to
>>> each
>>> since each will be using some chemicals that may have safety  
>>> concerns.
>>> So I think I'll take this opportunity to write up all the safety
>>> questions that I've thought about so far:
>>>
>>> (1) segregation of chemicals and food
>>>
>>> We have some food preparation space and a stove that people are
>>> apparently planning to use on occasion for preparing and eating in  
>>> the
>>> space.  What do we need to do to minimize the risk that the food
>>> preparation space becomes contaminated with materials used for
>>> chemistry
>>> or photographic work?  (One particular issue is about the sink,  
>>> which
>>> I'll break out into another point:)
>>>
>>
>> Though black and white chemistry is not especially toxic, (Developer
>> is not classified as toxic but often is an allergic compound for  
>> some,
>> causing skin irritation, stop bath (usually Glacial Acetic Acid), and
>> fixer (Sodium, Potassium or Ammonium Thiosulfate is fine when fresh,
>> but contains high amounts of silver when used and soluble silver will
>> make you look like a smurf) The biggest concerns would be with  
>> toners.
>> Selenium toner is extremely dangerous and needs to be handled with
>> great care. As with all things, general common sense and keeping food
>> away is smart.
>>
>> Here is the Kodak MSDS site. http://www.kodak.com/eknec/PageQuerier.jhtml?pq-path=4648&pq-locale=en_US&_requestid=1925
>>
>> Obviously, this is for basic B&W.
>>
>> Color chemistry is significantly more harmful and alternative
>> processes even more. (For example Daguerrotypes were developed in
>> Mercury Oxide vapor, the vapor is even worse for you than drinking  
>> the
>> stuff.)
>>
>>
>>> (2) safe storage and disposal of chemicals
>>>
>>> What do we need to do to ensure that we store and dispose of  
>>> chemicals
>>> safely?  If the kitchen sink is going to be used for food  
>>> preparation
>>> and washing dishes, it should probably not be used for chemical
>>> disposal
>>> even for some chemicals that could otherwise legally be disposed of
>>> this
>>> way.  Should we install a separate sink or other facilities for
>>> chemical
>>> disposal or washing glassware and photo trays?
>>>
>>
>> The only chemical you are required to handle properly in disposal is
>> fixer. Both Developer and Stop can be dumped down drains. Large
>> amounts of Fixer can't and the city regularly tests the disposed  
>> water
>> for high amounts of fixer/silver salts.
>>
>> You can safely pour dev/stop down into a toilet.
>>
>> Some photolabs allow people to dispose of used fixer on their  
>> premises
>> for a fee. Similar to waste motor oil.. Or you can pay safety clean
>> (sp?) to dispose of it for you.
>>
>>> (3) ventilation
>>>
>>> Meredith has been working on planning a fume hood for chemistry  
>>> work.
>>> Does the darkroom also need special ventilation arrangements in  
>>> order
>>> to protect people working there (or elsewhere in the space)?
>>>
>>> What prevents fumes captured by the fume hood from exiting back into
>>> the space through the kitchen stove vent intake?
>>>
>>> Does the fishbowl room or other parts of the space require  
>>> particular
>>> ventilation for safety apart from the fume hood?  (Especially if
>>> particular equipment ... like soldering irons ... may produce  
>>> various
>>> kinds of fumes.)
>>>
>>
>> Film development can be done out of a darkroom. The tanks are
>> (hopefully) light tight. The only exception is for those developing
>> 4x5 or larger where you use an open tub and hangers. For standard  
>> roll
>> development no ventilation is necessary.
>>
>> For developing paper (i.e. prints) a ceiling fan (bathroom style)
>> would be more than adequate.
>>
>> Toning should be done out of the darkroom and in fresh air.
>>
>>
>>> (4) training
>>>
>>> Further to a note on Talk:Safety by Shannon Clark, should there be
>>> some
>>> kind of training or briefing that people have to do before they can
>>> start using particular materials or equipment?  (This applies to  
>>> _all_
>>> tools and equipment in the space, not just chemicals!)  Shannon  
>>> wrote:
>>>
>>>  a thought, should we have some system akin to how TechShop handles
>>>  letting people use certain types of tools (i.e. in our case
>>> chemistry,
>>>  perhaps the darkroom, perhaps soldering tools) of only after they
>>> have
>>>  taken a course on Safety and Basic Usage (which in TechShop's case
>>> is
>>>  usually 1hr long)? --Shannonclark 23:42, 1 October 2008 (PDT)
>>
>> I would be more than happy to give trainings/classes.
>>
>> Previously to being a systems admin, my professional career was
>> working at pro photo labs in southern california, my degree is in
>> photography from CCA(c) and I used to volunteer with Harvey Milk  
>> Photo
>> Center. :)
>>
>> Mark
>>
>>
>>>
>>>
>>> -- 
>>> Seth David Schoen <schoen at loyalty.org> | Wol dir, werlt, daz du bist
>>>    http://www.loyalty.org/~schoen/   | also freudenriche!
>>>    http://vitanuova.loyalty.org/     |           -- Carmina Burana
>>> _______________________________________________
>>> Noisebridge-discuss mailing list
>>> Noisebridge-discuss at lists.noisebridge.net
>>> https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss
>>
>> _______________________________________________
>> Noisebridge-discuss mailing list
>> Noisebridge-discuss at lists.noisebridge.net
>> https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss
>>
>