Date: Fri, 30 Oct 2009 15:18:44 -0700
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From: Laurence Doemeny <ldoemeny**At_Symbol_Here**COX.NET>
Subject: Re: Roof top exhaust fan maintenance Policy
In-Reply-To: <5E9838FE224683419F586D9DF46A0E254DF0050937**At_Symbol_Here**MBOX.FLAS.CSI.CUNY.EDU>


What will the faculty be saying when a belt break or the bearing goes out and the system has to be shut down for an undetermined time and experiments need to shut down prematurely?  Don’t fall for that excuse.

Consider scheduling this sort of PM during scheduled seminars or other recurring events when most people are out of the laboratories.  I do not think that you want to schedule this sort of PM after hours for the very reasons that you mention.  My experience was in a non-academic setting.  We had scheduled monthly PM of the exhaust systems.  Outside the labs were flashing lights indicating that the hoods were not working.  Not quite LOTO but everyone knew what the flashing lights indicated.  Next to the lights were warning signs.

Good luck.

From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**] On Behalf Of James Saccardo
Sent: Friday, October 30, 2009 2:17 PM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: Re: [DCHAS-L] Roof top exhaust fan maintenance Policy

This issue has come up several times at our facility. Engineers do not want to go up to change a belt and cite visible losses in the ducts as a source of exposure. They do not know what might be exposed to and they are right. Design is the key, once you have a bad system, it can be difficult to work with. We have discussed off hour maintenance, but have nothing in writing. Never even discussed LOTO of fume hoods, perhaps out of fear of Faculty backlash. Saturdays and Sundays are a good time to perform maintenance, but what if someone has left something in the hood, running, uncapped, etc. Are the trades’ capable of recognizing chemical hazards in the lab? Abating the hazard without the lab staff?

We have locked machine rooms at the penthouse, but roof hatches (not bulk head) are not locked. Parapet also adds to concerns of exposure.

I can say that we have multi million dollar project ongoing to install strobic fans which may eliminate the need for maintenance and frequent belt changes. These new fans have redundancy built in and eject exhaust well out of the building envelope. I can’t wait to see how they perform and the noise they will produce.

I like the Arizona University model for lab hood LOTO, but how does this work in practice? Who handles the complaints from PI’s claiming they have grant deadlines to meet?

Have a nice weekend all

From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**LIST.UVM.EDU] On Behalf Of Wawzyniecki Jr, Stefan
Sent: Friday, October 30, 2009 9:55 AM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: [DCHAS-L] Roof top exhaust fan maintenance Policy

In general, maintenance staff working on rooftop fume hood exhaust equipment have indicated their concerns about being on a roof, and possibly being exposed to whatever is being vented. 


In a more specific laboratory situation, involving MOCVD (metal organic chemical vapor deposition), we have a lock-out tag-out policy, due to the severity of the toxic gases involved.




  1. Does anyone else have MOCVD labs, and to what extent are controls in place for protection of workers on roof tops?
  2. Does anyone else employ a LOTO policy?   
  3. Are roof tops key-accessible only?


Thanks for the feedback.


-Stefan Wawzyniecki, CIH, CHMM

 Univers ity of Connecticut

Think green before you print this email.

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