From: Tom Slavin <slavinosh**At_Symbol_Here**GMAIL.COM>
Subject: Re: [DCHAS-L] Upper limit of pH hazards
Date: Mon, 31 Oct 2016 13:01:56 -0500
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Message-ID: 018301d233a0$de95aa20$9bc0fe60$**At_Symbol_Here**gmail.com
In-Reply-To <7902331B-A8ED-4812-BD77-584064F6CDD5**At_Symbol_Here**keene.edu>


For some additional perspective, most soaps have a pH between 9 and 10
before dilution. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4171909/

In the world of metalworking, most metalworking fluids are buffered to
between 8.8 and 9.2. Dermatitis becomes a problem above 9.5. Machine
operators have intermittent contact with fluids when handling wet parts.
Gloves are often not worn because they may be a safety hazard for certain
machine environments.
https://www.stle.org/Shared_Content/TLT_Articles/Tech_Newsletter/The_Importa
nce_of_Controlling_the_pH_of_Your_Water-Diluted_Metalworking_Fluid.aspx?Webs
iteKey=d30229f1-d53b-48d7-99ae-d0ce9fea621d

Tom Slavin

-----Original Message-----
From: ACS Division of Chemical Health and Safety
[mailto:DCHAS-L**At_Symbol_Here**PRINCETON.EDU] On Behalf Of Stuart, Ralph
Sent: Monday, October 31, 2016 12:15 PM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] Upper limit of pH hazards

>why would one work actively in a chemistry lab without gloves?

The 3D printer pieces will not be used in the lab setting; there is concern
that the printed pieces could have micropores that retain corrosive liquids
longer than other types of materials. The student project will be to
determine the pH of the rinse water after each rinse to see how long it
takes to reach a "safe" level for the piece to leave the lab and enter the
world of things. Hence the question of what "safe" means.

Thanks to everyone for helping me to refine the question.

- Ralph

Ralph Stuart, CIH, CCHO
Chemical Hygiene Officer
Keene State College

ralph.stuart**At_Symbol_Here**keene.edu

---
This e-mail is from DCHAS-L, the e-mail list of the ACS Division of Chemical
Health and Safety.
For more information about the list, contact the Divisional secretary at
secretary**At_Symbol_Here**dchas.org

---
This e-mail is from DCHAS-L, the e-mail list of the ACS Division of Chemical Health and Safety.
For more information about the list, contact the Divisional secretary at secretary**At_Symbol_Here**dchas.org

Previous post   |  Top of Page   |   Next post



The content of this page reflects the personal opinion(s) of the author(s) only, not the American Chemical Society, ILPI, Safety Emporium, or any other party. Use of any information on this page is at the reader's own risk. Unauthorized reproduction of these materials is prohibited. Send questions/comments about the archive to secretary@dchas.org.
The maintenance and hosting of the DCHAS-L archive is provided through the generous support of Safety Emporium.