From:
Monona Rossol <0000030664c37427-dmarc-request**At_Symbol_Here**LISTS.PRINCETON.EDU>
Subject:
Re: [DCHAS-L] polymer curing question
Date:
Feb 26, 2019 15:32 UTC
Reply-To:
ACS Division of Chemical Health and Safety
In-Reply-To:
Thanks Tammy, and if they are doing urethane curing, we are looking at one or more of the isocyanates with TLV-TWAs usually set at 0.005 ppm. Whenever we think about safety and LELs, we need to also consider health and the TLVs.
Monona Rossol
-----Original Message-----
From: Tammy M. Lutz-Rechtin <tlutzrec**At_Symbol_Here**UARK.EDU>
To: DCHAS-L <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Sent: Tue, Feb 26, 2019 9:48 am
Subject: Re: [DCHAS-L] polymer curing question
Don't forget these two solvents, although common, are reproductive hazards (1B) with verifiable effects on pregnant women.
-Tammy Rechtin
From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
On Behalf Of Monona Rossol
Sent: Tuesday, February 26, 2019 8:38 AM
To: DCHAS-L**At_Symbol_Here**PRINCETON.EDU
Subject: Re: [DCHAS-L] polymer curing question
I repeat: DMF has a TLV-TWA of 5 ppm And add:
NMP has a WEEL-TWA of 10 ppm and NMP is on a short list proposed for a consumer product ban due to its toxicity.
Those health standards are miles below their LEL concentrations, so I worry about where that oven exhaust is going, especially if they are used in academic labs in
someone's project rather than in a planned industrial use. I have very low confidence in ventilation systems designed for academic labs and especially the locations at which they exhaust.
My advice: follow the ducts.
