From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU> On Behalf Of Kelsey Mesa
Sent: Monday, March 7, 2022 8:09 PM
To: DCHAS-L**At_Symbol_Here**Princeton.EDU
Subject: Re: [DCHAS-L] Ventilation Contaminated with Perchlorates

Thanks! Will take a look at Brookhaven's procedure and go see if I can locate the 2000 article. I perused the literature a bit but not sure I went back that far.

Kelsey,

 

Look at Brookhaven's procedure.  Also, Chemical Health and Safety (before JCHAS and now ACS-CHAS) had a good article on perchlorate hood demolition back in 2000.

 

Harry

 

From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU> On Behalf Of Kelsey Mesa
Sent: Monday, March 7, 2022 13:49
To: DCHAS-L**At_Symbol_Here**Princeton.EDU
Subject: [DCHAS-L] Ventilation Contaminated with Perchlorates

 

Hello! Have an interesting conundrum. Does anyone have experience with large-scale perchlorate decon? Mostly interested in if there are any thresholds out there and what was recommended. I'll include some details below about our situation. We have issues with access to spots in the ventilation where perchlorates are more likely to settle for testing. This is likely my biggest concern and question to answer.

 

• Positive tests for perchlorates were found in a fume hood on 1st floor and at the top of the ventilation system on both sides of the building. Very low quantities on swipe tests.
• Building has two "sides" to the lab ventilation. Positive results on both sides so we are currently suspicious of the entire system.
• No clear cause. There is use of perchloric acid for steel etching. No heat is applied. The system does have an electrical current applied to it while the steel is in the perchloric acid bath. 
• Is there a "safe" amount of perchlorate residue that is allowed? I would generally go for zero but it is not as straightforward when we are looking at potentially washing down the whole lab ventilation system.

Hopefully that provides some context. Would be happy to discuss more with anyone or if you have a good contact please share. We've talked to our other UC campuses but most were able to isolate an area of the ventilation for decon. We have been directed to a company called ACM and are beginning conversations with them about testing and potential decon.

 

Thank you!

Kelsey

kmesa**At_Symbol_Here**berkeley.edu

Chemical Hygiene Officer

EH&S Lab Safety Specialist

Office of Environment, Health & Safety

University of California, Berkeley

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