Safe sodium carbonate.

[kirk_keyes]

Patrick writes:

"Yes, we should know what inert ingredients are present or at least the definition of "inert" used in the MSDS. I have a feeling that somewhere is a general NIOSH definition of "inert" when that term is used in MSDS that would allow us to decide if it means "photographically inert". You could do us a service by finding such a definition if it exists.

 

"When an MSDS claims 100% purity, I believe the distributor can be held responsible for ingredients that are not included in that 100%."

 

OK Patrick, I thought I went over this before - MSDS are for SAFETY - not chemical purity. In case you have not noticed, MSDS stands for Material Safety Data Sheet, not Material Purity Data Sheet. You can not use an MSDS to determine chemical purity or the content of inert materials, especially in a bulk product like soda ash/sodium carbonate. AN MSDS is for your safety, not some application other than that, despite whatever feelings you may have about them.

 

You are right, there are regulations that say at what level a component must be listed in an MSDS. For a fuller discussion, you should look at 29CFR (Code of Federal Regulations) 1910.1200. Here's an overview of it:

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=10099&p_table=STANDARDS

 

Incase you don't have time to look it up, here's part of the section that pertains to your arguement:

 

1910.1200(g)(2)(i)©(1)

The chemical and common name(s) of all ingredients which have been determined to be health hazards, and which comprise 1% or greater of the composition, except that chemicals identified as carcinogens under paragraph (d) of this section shall be listed if the concentrations are 0.1% or greater; and,

 

1910.1200(g)(2)(i)©(2)

The chemical and common name(s) of all ingredients which have been determined to be health hazards, and which comprise less than 1% (0.1% for carcinogens) of the mixture, if there is evidence that the ingredient(s) could be released from the mixture in concentrations which would exceed an established OSHA permissible exposure limit or ACGIH Threshold Limit Value, or could present a health risk to employees; and...

 

Notice it only pertains to "all ingredients which have been determined to be health hazard" - not to all chemicals, not to inert compounds, not to inpurities, not to anything but all ingredients which have been determined to be health hazard. The only trace compounds you have to list are ones that are going to have health effects, not photographic effects.

 

Remember, these are for safety personnel when they come to save your butt when something explodes becasue you ("you" in general, not you specifically, Patrick) were mixing chemcials that were not being used for their intended puroses. They are also for "Right to Know" laws to protect you as an employee or end user of a product. MSDSs are for your safety.

 

So materials that are hazardous only have to be listed if they are in concentrations greater than 1.0%. Materials identified as carcinogenic only have to be listed if they comprise more than 0.1%.

Did you know there are even provisions for "Trade Secrets" in MSDSs? These compounds don't even have to be listed if OSHA determines that it will compromise the trade secrets of a company.

 

Remember, these are for safety personnel when they come to save you butt when something explodes becasue you ("you" in general, not you specifically, Patrick) were mixing chemcials that were not being used for their intended puroses. An MSDS is to help the fireman, not to show the amount of inert materials for your photographic application.

 

These reasons are why you can't trust an MSDS to have EXACTLY everything that is in a bottle of some product. I'm sure you've seen an MSDS for HC-110. The one I've seen (from around 1994) lists water at 15-20%. Do yo really thing that Kodak's quality control on the amount of water in HC-110 is really a 5% window. I don't think so. They have it listed like that to add some subterfuge so that you cannot just go out and reproduce their product by looking at an MSDS. And there is no telling what compounds are in it less than 1% that they don't have to tell you about. An MSDS is for safety, not industrial espionage.

 

And on something like soda ash (your pool pH plus for example), they only have to list what was added to the product. If they used 100% soda ash to fill the bottle, then that's what they write on the MSDS. But if that soda ash has 1% sodium choride as an impurity, then they may not have to list it, as it was not added by them in making up the contents of the bottle - it is an impurity from the mining process. AN MSDS is for safety, not chemcial analysis.

 

Patrick, you are just way off base in your use of MSDSs as a for of anything but the most coarse form of analysis.

 

Sorry about being so heavy-handed in this post, but this is an important point.

 

Kirk

[patrick_gainer]

Kirk,

 

Heavy handed is only a problem when you must lift it up again.

 

I did find the NIOSH regulations and the definition of inert. It may be quite true that the MSDS is for health, but as you also said, when 2% are specified as inert, that means something to health, whether it means anything to photography or not. There is a list of those ingredients that may be considered inert in an MSDS. It does nor include salt or bromides. The fact that 2% of the ingredients of pHPlus from hTh are specified as inert by MSDS is necessarilly significant by NIOSH regulations.

 

Another point I have been trying to make is that if you do not know the purity of the stuff you are measuring, don't bother to measure it, either by weight or by volume. Please don't quote obscure "possibilities" applied to formulas I do not present.

 

Furthermore, the speculations about what an error of 2% in measuring weight of sodium carbonate are off the wall. When a chemical is that important, it should be determined by titrarion or other analytical means than weight. 2% weight gain in small amounts of sodium carbonate can occur while you are weighing. You will not be able to prove to yourself, let alone to me, that a 2% gain in weight is accompanied by a 2% gain in volume when the weight gain is in water of crystallization.

 

The web site to see is:

http://www.ilpl.com/msds/ref/niosh.html

[rowland_mowrey]

Patrick;

 

Kirk made an excellent point and it sounds as if you miss his point completely. I understand what he is saying and it is of great significance to this whole discussion if you would only listen to what he has said and sit back and consider it.

 

He is validating the potential problem that I have pointed out. Neither of us are saying it is a problem or that it will be a problem, but rather that the potential exists for it to be a problem at some time or another. The statistics are against you doing it your way without having someone at some time have a problem using your recommendations.

 

The MSDS purity is no guarantee to us for either our developers or our safety. Believe Kirk, he is right.

 

And, Kirk, thanks. You state it more clearly than I because you have much more first hand experience in MSDS information than I do. I just have the photo experience end of it. I appreciate the clarity of your comments here.

 

Ron Mowrey

[kirk_keyes]

"I did find the NIOSH regulations and the definition of inert."

 

Well, what did you find? Could you share it?

 

"It may be quite true that the MSDS is for health, but as you also said, when 2% are specified as inert, that means something to health, whether it means anything to photography or not."

 

Not "may be quite true" but IS quite true. I did not say that 2% were specified as inert, but you are right, that means something - to health, not photography. I believe Ron supposed that the soda ash you are using for sodium carbonate would probably assay out to about 98%. And he is quite possibly right about that.

 

But this brings up another important issue. Inert for you, or me, or and MSDS may not all be the same list of inert compounds. It all depends on what is your intended application. Inert for MSDS and inert for photography are probably not the same thing.

 

"There is a list of those ingredients that may be considered inert in an MSDS. It does nor include salt or bromides."

 

Could you give a link to that list?

 

"The fact that 2% of the ingredients of pHPlus from hTh are specified as inert by MSDS is necessarilly significant by NIOSH regulations."

 

Yes, significant for health and fire safety.

 

"Another point I have been trying to make is that if you do not know the purity of the stuff you are measuring, don't bother to measure it, either by weight or by volume."

 

You don't really mean that last sentence - so we can just dump some arbitrary amount of the desired reagents into a container and add an arbitrary amound of water to it? I don't think you are going to get very satisfactory results that way for most of the developers you are making. And even if you are happy with the performance of solutions made up this way, many others will not as they may expect more repeatable results.

 

"Please don't quote obscure "possibilities" applied to formulas I do not present."

 

I will not and I don't believe I have. But it is those obscure possibilities (or less than obscure possibilities that we don't plan for) that may cause us real issues.

 

"Furthermore, the speculations about what an error of 2% in measuring weight of sodium carbonate are off the wall. When a chemical is that important, it should be determined by titrarion or other analytical means than weight. 2% weight gain in small amounts of sodium carbonate can occur while you are weighing. You will not be able to prove to yourself, let alone to me, that a 2% gain in weight is accompanied by a 2% gain in volume when the weight gain is in water of crystallization."

 

I'm with you on this - if want to used kitchen measuring devices when doing kitchen chemistry experiments, that's fine with me. And it seems perfectly suited as well.

 

But you know - it really depends on the chemical. There are some compounds that are deemed "primary standards" that wieghing is actually the most precise and prefered method of measuring. Of course you have to have the standard in a known condition (i.e. dried at a certain temperature).

 

I just believe that if one wants to have a higher level of certainty and repeatablility one would use more precise tools and supplies of know purity.

 

If you were paying money for pre-mixed photo chemicals, wouldn't you want them to be using precise methods of measurement when preparing solutions? Would you feel good about buying a bottle of HC-110 that was made in someone's kitchen with teaspoons and measuring cups? I guess what we have found out here is that perhaps that would be fine with you. I'm just looking for something with a little better quality.

 

"The web site to see is: http://www.ilpl.com/msds/ref/niosh.html"

When I cut and pasted this link into my browser, it goes to a page of advertisements, and says "page can not be found" at the bottom...

 

Kirk

[kirk_keyes]

Patrick, Ron -

 

Perhaps we should be thankful that the photographic process (at least B&W) when practiced by amateurs, is a very forgiving process. You can be off on exposure, development, mixing of chemicals, time in chemcials... numerous other things, and still get what can be considered acceptable results.

 

Kirk

[lex_jenkins]

"These compounds don't even have to be listed if OSHA determines that it will compromise the trade secrets of a company."

 

=================================

 

Strictly speaking, OSHA doesn't determine trade secrets or whether they will be compromised. The manufacturer presents its arguments for withholding certain information from the MSDS and OSHA either agrees or disagrees.

 

It seems like an insignificant point only until you're inside the complex relationships between government research (NIOSH) and regulatory (OSHA, MSHA, EPA) agencies and private industry. Then every nitpicking detail is scrutinized.

 

For example, when I was a safety and health inspector for federal OSHA, we referred to hazards as "apparent violations" of an OSHA regulation. If I used the word "apparent" or "appeared", etc., in any other context in my report my supervisor would send it back for a rewrite. So I wasn't even permitted to write "There appeared to be a scaffolding without safety rails, but the employer denied it was in use", or "Apparently an unguarded table saw was no longer in use".

 

I make this mundane point because it "appears" that Ron, Patrick and Kirk have become stuck on the merry-go-round of technicalities at the risk of falling off into tautologies.

 

In other words, it "appears" that everyone has made his point more than thoroughly and the discussion is now at the stage where each participant is expecting or even demanding that other participants acknowledge where their statements have been either erroneous, imprecise or simply did not differentiate between technicalities in terminology.

 

So, let's please wrap it up unless there is something substantially different to offer that will contribute to this thread. I'd like to add this thread to the list of essential reading, linked via the "About" option on the home page for this forum, but I'd rather not have to go in and prune out the superfluous, redundant or simply argumentative.

 

And please don't misunderstand me: I appreciate everyone who contributes in a positive manner to the body of factual information on these forums. It's a necessary complement to the more frequent speculations, casual observations and artistic flights of fancy (of which I am often guilty).

[rowland_mowrey]

Lex;

 

Thanks for the reality check. I agree with you.

 

Ron Mowrey

[jerry_friedman]

Well, after the contributions about sodium carbonate made by

Patrick and Ron et al. I am beginning to understand why my

martinis have been off this summer. I think i am going to go

back to mixing them with sodium sulfite and just doubling the

amount of ice and olives. I know, I know, this is defeatist and will

cost me more in the long run, but simplicity has its virtues.

 

This is truly the very best thread!

 

Jerry

[rowland_mowrey]

Jerry;

 

Shaken or stirred.

 

You know that ice behaves differently depending....

 

LoL.

 

Thanks.

 

Ron Mowrey

[patrick_gainer]

I will make one last point on this thread and no more, for which I'm sure you all are grateful. I do not apply slapdash methods when I am testing a formula for presentation. If a formula is forgiving enough to make use of teaspoon measurements, I see no reason not to say so. In all my writings thus far, at least for processes that are not carried to completion, I have specidied both weights and volumetric measures so that those who do not have a scale or balance may try the process. There are times when I say something like "Throw in a teaspoon of this and a tablespoon of that" but those processes are not done by time and temperature, but are judged complete when a cetain effect is observed.

 

I do not rely on anecdotal results, nor do I recommend that anyone else do so. That is why I questioned the sensitivity analysis given by Ron a while back. A proper sensitivity analysis of any of our commonly used developers will show quite a bit of leeway in accuracy of measurements. In most you will not see a significant difference between anhydrous sodium carbonate and the monohydrate when you use equal weights.

 

I am not in favor of inaccuracy. I am in favor of knowing what you need and finding how to get it economically. Any time you find a formula where quantities are specified volumetrically, you may certainly weigh those volumes the first time you use it so that you can repeat whatever results you get.

[rowland_mowrey]

To Patrick and others;

 

Please read this thread.

 

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=008j7g

 

It is Dannys experience with a published formula in Anchell.

 

I'm sorry to have added another post here Patrick, but I was just made aware of this.

 

Ron Mowrey

[lex_jenkins]

Okay, this thread has been added to the list of interesting threads accessible by clicking on the "About" button on the forum's home page.