From: TILAK CHANDRA <0000058f112ac338-dmarc-request**At_Symbol_Here**LISTS.PRINCETON.EDU>
Subject: Re: [DCHAS-L] nitric acid distillation
Date: Sun, 18 Oct 2020 02:20:06 +0000
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU>
Message-ID: CH2PR06MB66147EF47302E3CAAAE3A6D988010**At_Symbol_Here**CH2PR06MB6614.namprd06.prod.outlook.com
In-Reply-To


Hi John:


There is also a better use of chlorosulfonic acid in the preparation of sildenafil citrate (5-(2?-Alkoxyphenyl)-pyrazolo-[4,3-d]-pyrimidin-7-ones). The first synthesis of sildenafil by Pfizer involves the use of chlorosulfonic acid. It provides a selective product on the 5'-position of the phenyl ring, permitting ready coupling with a range of amines to afford the sulphonamide products. 


I was involved in this prep for a company, and the reaction is very straightforward and clean without formation of any side products . You just need to dry the starting material before using it for sulfonation.


https://www-sciencedirect-com.ezproxy.library.wisc.edu/science/article/pii/0960894X9600323X


I hope you're doing well.


Tilak



From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU> on behalf of JOHN L STRAUGHN <0000120dde6ec15c-dmarc-request**At_Symbol_Here**LISTS.PRINCETON.EDU>
Sent: Saturday, October 17, 2020 5:24 PM
To: DCHAS-L**At_Symbol_Here**Princeton.EDU <DCHAS-L**At_Symbol_Here**Princeton.EDU>
Subject: Re: [DCHAS-L] nitric acid distillation
 
Has Robert Goddard been consulted yet? Somebody has to ask this rocketeer about his liquid fuels rocket motor; not so straightforward to make one and run it safely. BTW: anyone notice the HazMat headlines a few days ago? Some fiendish idiot in Philly (my old area near Germantown, no less) got some chlorosulfonic acid somehow, not to mention splashing a woman in the face with it. [ You can get anything you want, at the good ole internet, walk right in, it's around in back, just about a mile from the railroad track ...... apologies to Arlo] I'm hopeful this guy will be careful with the fuming nitric, anyway. Better that than chlorosulfonic as I have personally experienced.

From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU> on behalf of pzavon**At_Symbol_Here**ROCHESTER.RR.COM <pzavon**At_Symbol_Here**ROCHESTER.RR.COM>
Sent: Saturday, October 17, 2020 10:05 AM
To: DCHAS-L**At_Symbol_Here**Princeton.EDU <DCHAS-L**At_Symbol_Here**Princeton.EDU>
Subject: Re: [DCHAS-L] nitric acid distillation
 
There may well be some legal violation, or unacceptable liability risk, in allowing the student to take the synthesis product home, but I don't see how there can be a DOT violation.  The HazMat transportation regulations of the DOT apply to "transportation in commerce."  Even with the expansive definition of commerce that has been used for decades, this does not appear to be "in commerce" unless the student intends to sell it from home.


Peter Zavon, CIH
Penfield, NY

PZAVON**At_Symbol_Here**Rochester.rr.com



-----Original Message-----
From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU> On Behalf Of Yaritza Brinker
Sent: Friday, October 16, 2020 3:06 PM
To: DCHAS-L**At_Symbol_Here**Princeton.EDU
Subject: Re: [DCHAS-L] nitric acid distillation

You asked
        What are the chances the student will try to do this on their own if they cannot do it at school?

You can't keep people from behaving badly on their own time. All you can do is explain why they can't do it on your time.

Furthermore, it would be a violation of DOT laws to allow the student to take the synthesis product home.

Yaritza

-----Original Message-----
From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU> On Behalf Of davivid
Sent: Friday, October 16, 2020 2:03 PM
To: DCHAS-L**At_Symbol_Here**Princeton.EDU
Subject: Re: [DCHAS-L] nitric acid distillation

** External Email **

If this is a graduate degree granting institution, would such work by graduate students be allowed?

What are the chances the student will try to do this on their own if they cannot do it at school?

Dave Lane
Principal
Clavis Technology Development

On 10/16/20 10:02 AM, Joseph DiVerdi wrote:
> When the protocol is to use conc sulfuric acid to lubricate the ground
> glass joints you know you're getting into some serious chemistry. ;)
> jadv
>
> Clearly, this work is edgy and exciting (!). It oughtn't be undertaken lightly and ought to be undertaken under the supervision of or at least with the counsel of an experienced practitioner of these particular arts. The student is to be commended for interest, enthusiasm and attempt at persuasion. The instructor is to be commended for caution, diligence and requesting advice.
>
> If I were a decision maker in this institution I would (regretfully) deny the project. There is insufficient knowledge and experience to work with these materials and there isn't a short path between current expertise and that necessary to effectively carry out the work. As much as I seek to encourage "pushing the envelope" among my own students I do not hear a compelling case for this project. Perhaps that will be a suitable piece of the project and this student's education to develop a strong enough case (in all the dimensions this entails) to convince the authorities (instructor included) of its propriety.
>
> It is my and my department's intent to include a new, elective lecture and laboratory course in spring 2020 entitled "Energetic Materials" where we intend to join up interest in propellants and other sundry items with topics of physical chemistry. Thus, I've been following this thread with great interest. At this moment even with our collective experience I judge that we will not be synthesizing fuming nitric acid next spring.
>
> There is a great, read for this topic (broadly defined). It is entitled "Ignition!" by John D. Clark (1972, Rutgers University Press, NJ) and is written in the style of a memoir. It is available at a modest cost from Amazon (used, paperback and inexpensive) and also as a PDF file elsewhere on the grey web. I purport it to be a must read (necessary but not sufficient) for anyone interested in pursuing this line of interesting and important chemical work.
>
> Good luck!
>
> jadv
>
> On Thu, 15 Oct 2020 8:34 PM, Gerald Solley wrote:
>> Fuming Nitric Acid for HYPERGOLIC combustion.
>>
>> This is theoretical, for discussion or consideration .
>>   Molarity values are excluded
>>
>>
>> Warning:  Dangerous Strong oxidizer:  location, ventilation, and
>> separation: KEEP AWAY FROM ORGANICS, SEE NOTES *1
>>
>> I believe this would be a facile lab scale synthesis of a usable fuming Nitric acid. This method uses sodium bisulfate and sodium nitrate ( or KNO3) .   I omitted the stoichiometry, though I believe a slight excess of the Bisulfate salt will drive the reaction to completion.  I believe, the salts do not need to be anhydrous, but close to it. Some salt bound H2O is needed for the reaction to proceed.
>>
>> A simple distillation apparatus
>> should high quality, meticulously cleaned and dry glass, with the
>> fittings lubricated with concentrated H2SO4. *2. The dry mixture is heated until the acid distills over.
>>
>> The advantage to this would be not having
>> to deal with the exothermic reactions, risks, cost and  need to redistill when using H2SO4.   In addition, the product which
>> distill over is high yield and high concentration fuming nitric acid.
>>
>> The density should be close to 1.5gr/cc, (the closer to  1.514gr/cc
>> the more concentrated)
>>
>> UV Light causes decomposition to NO2 with yellowing.
>>
>>
>> When doing this reaction, one must be careful,  when handling the
>> distillate of fuming HNO3 one should not wear gloves as they burst in
>> to flames on contact.*3
>>
>> The fuming acid should be stored in clean, dry SHATTERPROOF amber
>> glass to block UV.*4
>>
>> Containers should not be filled more than 1/2, to allow room for
>> expansion a gas.  The bottles must be carefully be vented monthly. *5
>>
>> I'm have no knowledge about long term storage, but I think it prudent to use it quickly and not keep it around.   In a fire proof, acid cabinet.*6
>>
>> NOTES:
>> 1.
>> Fuming Nitric acid is a strong oxidizer.
>> FIRE DANGER DUE TO HYPERGOLIC COMBUSTION ON CONTACT WITH MANY
>> SUBSTANCES. ( eg lab gloves catch fire)
>> HNO3 emits dangerous corrosive vapors.
>> Keep combustable material away from
>> reaction areas.
>> Fire and/or explosion risk
>> from, but not limited to:
>> bases, reducing agents, metal powers, alkalies, cyanides, sulfides,
>> carbides and cellulose ( paper/wood).
>>
>> This should only be done in a proper
>> fume hood,  with fire suppression nearby  and under supervision of a
>> chemist competent in laboratory arts and safely.
>>
>> 2. Ground glass joints  must be lubricated with H2SO4. Concentrated
>> sulfuric acid will allow easy separation of ground glass.  Standard ground glass greases could be oxidized and should be avoided due to the risk.
>>
>> 3.  Latex and Nitrile  gloves, will instantly combust in contact with HNO3, melt and stick to skin.  I've read that historically, in fact, no gloves were preferred to latex and nitrile (not endorsed just included to elucidate risk).  Special gloves are,  face shields and PPE are available. Small quantities may be  dealt with in fume hood. Consult MSDS.
>>
>> 4.
>> UV light results in decomposition to NO2 with yellowing, darker on higher concentrations,
>>   and could cause vapor pressures exceeding the container limit, or causing violent release on opening.  Brown or Amber glass will block UV. Glass must should be shatterproof.
>>
>> 5.  Glass bottles containing fuming HN03 must only be filled 1/2 way
>> to allow and gases to expand.  In addition, they must carefully be
>> vented at minimum monthly to prevent dangerous pressure build up.
>>
>> 6.  Store in tightly closed bottle, in cool dark, dry place, and should be locked up and separate from other acids, alkalies, reducing agents and combustibles noted herein.
>> Consider a spill:  would it instantly ignite  anything nearby, then
>> mitigate risk.
>>
>> See NFPA 43A, Code for the Storage of Liquid and Solid Oxidizers. Do not store above 23¡C (73.4¡F).
>>
>>
>>
>>
>>
>>> On Oct 15, 2020, at 10:15 AM, Yaritza Brinker <YBrinker**At_Symbol_Here**fele.com> wrote:
>>>
>>> ?
>>>
>>> Laurie,
>>>
>>>
>>>
>>> As you mentioned, this is a very good opportunity for education. I encourage you to use this opportunity to develop a short seminar series on hazard assessment and good experiment planning practices for your students. Small companies will expect them to know who to do this on their own at the bachelor level.
>>>
>>>
>>>
>>> Rather than calling out this particular case, you could use an experiment that is already being performed in the university as a case study or possibly an experiment that had been previously declined because it didn't pass hazard analysis. You could even tie it back to the course work by doing theoretical calculations related to the safety of the experiment.
>>>
>>>
>>>
>>> Take a cyanide titration for example. You could calculate the amount of cyanide gas released if the pH were to drop during the titration. The lethal respirable dose is available. You can use this information to determine the scale of the experiment. You could even use your local ER response time to have the students think about the risk to human life if the experiment were to go seriously wrong.
>>>
>>>
>>>
>>> Good Luck!
>>>
>>>
>>>
>>> Yaritza Brinker
>>>
>>> 260.827.5402
>>>
>>>
>>>
>>> *From:* ACS Division of Chemical Health and Safety
>>> <DCHAS-L**At_Symbol_Here**Princeton.EDU> *On Behalf Of *Laurie Yoder
>>> *Sent:* Wednesday, October 14, 2020 10:12 AM
>>> *To:* DCHAS-L**At_Symbol_Here**Princeton.EDU
>>> *Subject:* [DCHAS-L] nitric acid distillation
>>>
>>>
>>>
>>> *** External Email ***
>>>
>>> We have a senior chem student who has proposed making fuming nitric acid by reaction of fertilizer and concentrated sulfuric acid. (wants to make rocket fuel because this is what they do on youtube...) After my first "no way on earth are you going to do this!" they looked up some safety information and sent me the "proposal", copied below. This is a highly motivated student who loves chemistry and legitimately wants to learn and try new things so I hate to shut them down without taking the opportunity for education. My problem is that everything about this looks high-risk, and I need some help to sort it out to best communicate what the concerns are, other than "you're going to injure yourself and damage the property."
>>>
>>>
>>>
>>> My question for the group is what do you see as the top risks here and what would someone (in theory) need to do to mitigate them? I'm thinking (hoping!) it should become obvious to the student why we can't manage it here.
>>>
>>>
>>>
>>> Thanks for your help!
>>>
>>> Laurie
>>>
>>>
>>>
>>> This is from the student:
>>>
>>> "I propose to produce fuming nitric acid using distillation of an
>>> alkali nitrate salt heated with concentrated sulfuric acid. Sodium
>>> Nitrate melts at 308 C and is an oxidizer which begins to break down
>>> but does not have a flash point. The high concentration Sulfuric
>>> Acid
>>> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpu
>>> bchem.ncbi.nlm.nih.gov%2Fcompound%2FSodium-nitrate%23section%3DBoili
>>> ng-Point&amp;data=04%7C01%7C%7C9620a32a97f1439cd69b08d871feeeea%7C99
>>> 4c3e8bb42845fb8640593ef0303f7f%7C0%7C0%7C637384687033058835%7CUnknow
>>> n%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwi
>>> LCJXVCI6Mn0%3D%7C1000&amp;sdata=eEwmhM8zgVuVEBGYJLfqQsKqYjH%2BB4oLQv
>>> 5juS%2FFHcc%3D&amp;reserved=0
>>> <https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fp
>>> ubchem.ncbi.nlm.nih.gov%2Fcompound%2FSodium-nitrate%23section%3DBoil
>>> ing-Point&amp;data=04%7C01%7C%7C9620a32a97f1439cd69b08d871feeeea%7C9
>>> 94c3e8bb42845fb8640593ef0303f7f%7C0%7C0%7C637384687033058835%7CUnkno
>>> wn%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWw
>>> iLCJXVCI6Mn0%3D%7C1000&amp;sdata=eEwmhM8zgVuVEBGYJLfqQsKqYjH%2BB4oLQ
>>> v5juS%2FFHcc%3D&amp;reserved=0> will have some water in it but the
>>> Nitric acid being continuously produced boiling off should keep the
>>> temperature below 100 C anyway.
>>> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpu
>>> bchem.ncbi.nlm.nih.gov%2Fcompound%2F944%23section%3DBoiling-Point&am
>>> p;data=04%7C01%7C%7C9620a32a97f1439cd69b08d871feeeea%7C994c3e8bb4284
>>> 5fb8640593ef0303f7f%7C0%7C0%7C637384687033058835%7CUnknown%7CTWFpbGZ
>>> sb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0
>>> %3D%7C1000&amp;sdata=msV20epxYaZnaxPFw4VwacZvI9fRStP4PXGbZ4RU98A%3D&
>>> amp;reserved=0
>>> <https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fp
>>> ubchem.ncbi.nlm.nih.gov%2Fcompound%2F944%23section%3DBoiling-Point&a
>>> mp;data=04%7C01%7C%7C9620a32a97f1439cd69b08d871feeeea%7C994c3e8bb428
>>> 45fb8640593ef0303f7f%7C0%7C0%7C637384687033058835%7CUnknown%7CTWFpbG
>>> Zsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn
>>> 0%3D%7C1000&amp;sdata=msV20epxYaZnaxPFw4VwacZvI9fRStP4PXGbZ4RU98A%3D
>>> &amp;reserved=0> The temperature will be continuously monitored and
>>> the heater will be shut off if the temperature exceeds 150 C.
>>>
>>>
>>> "The reaction vessel will be a round bottom flask with a heater from there the gaseous nitric acid will run through a still cooled with ice water and covered with aluminum foil to minimize the breakdown of nitric acid into NO2 due to UV light. The product will be collected in another round bottom flask and the excess NO2 and uncondensed Nitric acid will be bubbled through a water trap (we shouldn't use rubber tubing here).
>>>
>>>
>>> "Products- Sodium Sulphate is a common fertilizer just like sodium nitrate the last of the acid in the reaction chamber can be neutralized and the waste can be easily disposed of as solid waste or mixed into the compost pile.
>>>
>>>
>>> "Fuming Nitric Acid- This is the product we are interested in collecting. It will be used by XXX as the oxidizing agent in a model rocket. Fuming Nitric acid quickly destroys Nitrile gloves, setting them alight and melting them. For this reason an alternative is necessary. Vinyl gloves deform a bit but do not melt or burn on contact with Fuming Nitric acid. Therefore obtaining Vinyl gloves and a Vinyl smock could also be a productive option. That said, direct skin contact with fuming Nitric acid is not as damaging to the skin as solutions containing more water. As long as it is promptly removed working without gloves would potentially be a viable option. All work will take place in the hood because gaseous nitric acid and NO2 are continuously released. Once the Fuming Nitric Acid is isolated it can be stored indefinitely in an amber glass container with a teflon sealed lid.
>>>
>>>
>>> "Nitric acid from water trap- This product's density can be measured to determine its concentration. Then it can be stored in glass for use in other experiments.
>>>
>>>
>>> "NO2 gas- We will do our best to minimize the production of this side product. Nitric acid breaks down into NO2 faster at high temperature and with more light. We will minimize the necessary temperature in the reaction pot, and ice the condensing regions and product. All the glassware connections will be greased using the same sulfuric acid in the reaction pot which would be a good reason to wear vinyl gloves. This will seal the reaction  with the overpressure continuously bubbling into the trap where more of the gas can condense and the extra NO2 will be pumped out of the hood where the entire synthesis will occur.
>>>
>>> "Additional considerations
>>> Limiting personnel access- Because the Chemical prep room is the only hood which is off limits to most students during the day it would be the ideal location for this synthesis. 2 people will monitor the reaction at all times and eyewashes and a shower are readily available. There is a designated fire extinguisher on hand and the labspace is not used too much so it can be cleaned up and sorted to meet our needs.
>>> Eye protection- Eye protection will be worn at all times
>>>
>>> "YouTube Sources
>>> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fww
>>> w.youtube.com%2Fwatch%3Fv%3DQmCdrDLyNXQ%26t%3D502s&amp;data=04%7C01%
>>> 7C%7C9620a32a97f1439cd69b08d871feeeea%7C994c3e8bb42845fb8640593ef030
>>> 3f7f%7C0%7C0%7C637384687033058835%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC
>>> 4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;
>>> sdata=5ooBb6NQTV7aM056Ke7dcaQCZaoaTyp9BVbFiR2oL7s%3D&amp;reserved=0
>>> <https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fw
>>> ww.youtube.com%2Fwatch%3Fv%3DQmCdrDLyNXQ%26t%3D502s&amp;data=04%7C01
>>> %7C%7C9620a32a97f1439cd69b08d871feeeea%7C994c3e8bb42845fb8640593ef03
>>> 03f7f%7C0%7C0%7C637384687033058835%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiM
>>> C4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp
>>> ;sdata=5ooBb6NQTV7aM056Ke7dcaQCZaoaTyp9BVbFiR2oL7s%3D&amp;reserved=0
>>> >
>>> https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fww
>>> w.youtube.com%2Fwatch%3Fv%3DaUzMms62hKw&amp;data=04%7C01%7C%7C9620a3
>>> 2a97f1439cd69b08d871feeeea%7C994c3e8bb42845fb8640593ef0303f7f%7C0%7C
>>> 0%7C637384687033058835%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiL
>>> CJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=NEvMg
>>> bzhvnYLrHOtQNErj3B5vavRMStrhCzKOrpYhkQ%3D&amp;reserved=0
>>> <https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fw
>>> ww.youtube.com%2Fwatch%3Fv%3DaUzMms62hKw&amp;data=04%7C01%7C%7C9620a
>>> 32a97f1439cd69b08d871feeeea%7C994c3e8bb42845fb8640593ef0303f7f%7C0%7
>>> C0%7C637384687033058835%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAi
>>> LCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=NEvM
>>> gbzhvnYLrHOtQNErj3B5vavRMStrhCzKOrpYhkQ%3D&amp;reserved=0>
>>>
>>> "Duke OESO Guidelines for Safe Use of NITRIC ACID...[lots more
>>> copied and pasted stuff from internet...]
>>>
>>> --
>>>
>>> *Laurie M. Yoder, PhD
>>> *Assistant Professor of Chemistry and Chemical Hygiene
>>> OfficerEastern Mennonite University
>>> 540.432.4420
>>>
>>>
>>>
>>> --- For more information about the DCHAS-L e-mail list, contact the
>>> Divisional membership chair at membership**At_Symbol_Here**dchas.org
>>> <mailto:membership**At_Symbol_Here**dchas.org> Follow us on Twitter **At_Symbol_Here**acsdchas
>>>
>>>
>>>
>>>
>>> *_Electronic Transmission Confidentiality Notice_*
>>>
>>> The information contained in this electronic transmission is private, confidential, the property of the sender, and intended for the use of the recipient(s), **only. If you are not the addressee, any disclosure, copying, distribution or use of this information for any purpose is strictly _prohibited_. If you have received this information in error, please notify the sender, *YBrinker**At_Symbol_Here**fele.com*,immediately by e-mail and then delete this message. Thank you.
>>> [FE.EN.1]
>>>
>>> --- For more information about the DCHAS-L e-mail list, contact the
>>> Divisional membership chair at membership**At_Symbol_Here**dchas.org
>>> <mailto:membership**At_Symbol_Here**dchas.org> Follow us on Twitter **At_Symbol_Here**acsdchas
>> --- For more information about the DCHAS-L e-mail list, contact the
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