From: "Sirvent, Tara" <tsirvent**At_Symbol_Here**VANGUARD.EDU>
Subject: Re: [DCHAS-L] Lab Safety Caps in Chem Labs
Date: Thu, 22 Aug 2013 17:55:43 +0000
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: D643101E-6FDD-49BD-98DF-7979AFE4244E**At_Symbol_Here**
In-Reply-To <180948909.2352640.1377189050982.JavaMail.root**At_Symbol_Here**>

Hi! We are in CA. And I believe that the regulation is about the hood space in the chem labs is 1910.1450.C.4.(b)
This regulates that there needs to be 2.5' of linear hood space per individual when they spend "most of their time working with chemicals."

We have different limits depending on the hood space and which lab courses "spend most of their time working with chemicals", or more pragmatically if we define that they don't spend most of their time with chemicals and we wouldn't be bound by that Best Practice - then how much equipment do we have for how many students? Or even more importantly, how many students can one individual supervise to prevent and react to if an emergency were to occur.

For example, we have higher limits for Gchem than we do Ochem. OChem is more complex working with vacuums and intricate glassware does need the hood space since they primarily work with chemicals.

Our rooms are smaller than the typical lab room at a community college and has fewer hoods. So just saying 24 students as a golden rule is not a good criteria to use. My recommendation is to analyze your space, ventilation, and equipment requirement/constraints and develop individualized occupancy limits. I then would present this to your Dean and make sure they understand that if we don't follow Best Practices we might be putting ourselves in a liable position.

Tara Sirvent, PhD

Associate Professor of Biochemistry

Chair, Department of Chemistry

On Aug 22, 2013, at 9:30 AM, >

It's the beginning of a new semester here in the beleaguered California community colleges, and there is again an administrative push to over enroll students in chem labs.

So I am interested in the history of the 24-25 chem lab safety caps. Does anyone know why 24-25 has been deemed the upper safety limit and what evidence was used? Also, exactly what agencies and organizations (in the US and abroad) besides ACS and LSI recommend these caps?

For those of you in California, is it true that when a new chem lab is designed for a state-funded school that the lab design is based on 24 students? This is what I've heard, and architects seem to design California chem labs around this magic 24, but is it state-mandated?

Marjorie Samples
Folsom Lake College, Folsom California

Vanguard University

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