Date: Wed, 8 Apr 2009 08:12:01 -0400
Reply-To: List Moderator <ecgrants**At_Symbol_Here**UVM.EDU>
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: List Moderator <ecgrants**At_Symbol_Here**UVM.EDU>
Subject: 12 Re: [DCHAS-L] Class lab fume hoods?

Here is a compilation of yesterday's responses to my inquiry about  
trends in class lab ventilation practices. My sense of the responses  
is that the 21st approach to class lab design is to throw lots of air  

at the situation. It will be interesting to see what we think of this  

as campuses start putting together Climate Action Plans that fulfill  
the President's Climate Commitment to achieve carbon neutrality  

Thanks for all who replied.

- Ralph

From: Derek Fultz 
Date: April 7, 2009 9:39:28 AM EDT (CA)
Subject: Re: [DCHAS-L] Class lab fume hoods?

Our new Organic Teaching Laboratories have a small Ventilated Work  
Station for each pair of non-majors, and a full 5ft. hood for each of  

the students in the majors course.  We're having the same debate as we  

look to renovating our General Chemistry laboratories. I'd be  
interested in hearing the responses you get.


Derek R. Fultz
Director of Operations, Safety, and Compliance
Department of Chemistry
University of Illinois, Urbana-Champaign
306 Noyes Laboratory, MC-712
505 South Mathews Ave.
Urbana Illinois 61801
Office Phone:217-265-0294
Cell Phone: 217-369-8924

=0CFrom: "Caldwell, Charles D" 
Date: April 7, 2009 9:41:10 AM EDT (CA)
Subject: RE: [DCHAS-L] Class lab fume hoods?

Our building remodel was completed in 2000.  For General,  
Introductory, and Forensic labs the rooms have 3 hoods for up to 24  
students per section.  For the experiments we do this is entirely  

For synthesis labs (Organic, Inorganic) the room has 12 double hoods.   

Theoretically this could handle 24 students working individually, but  

we usually use 1 or 2 hoods for the setups.  These days students  
usually work in pairs so that is not a problem.


Charles D. Caldwell, Ph.D.
Laboratory Coordinator
Chemistry Department
Colorado State University-Pueblo
2200 Bonforte Blvd
Pueblo, CO 81001

=0CFrom: "Kevin Burns" 
Date: April 7, 2009 10:05:47 AM EDT (CA)
To: "Ralph Stuart" 
Subject: RE: [DCHAS-L] Class lab fume hoods?

I work at Alvernia University in Reading PA.  Our science center  
recently opened in the fall of 2006.  It is a two story building with  

five labs on each floor.  Three rooms are classroom/lab combinations  
and the other two are just labs.  The lab/classroom combinations have  

24 student desk in the front of the room for lecture and the back of  
the room has six lab benches, 24 lab stools and 6 extra large fume  
hoods to each accommodate 4 students.

Hope this helps

K. Burns
Director of Science Laboratory Services and Safety
Dept. of Science & Math
Alvernia University

=0CFrom: Allen Aloise 
Date: April 7, 2009 10:21:35 AM EDT (CA)
Subject: Re: [DCHAS-L] Class lab fume hoods?

At Harvard we have 2 students per fume hood in introductory organic  
labs and 1 student per fume hood in advanced labs.  I believe we would  

aim to keep a 2 student per fume hood ratio in future renovations.

I hope all is well.


Allen Aloise, Ph.D.
Science Safety Officer
Department of Chemistry and Chemical Biology
Harvard University
12 Oxford St.
Cambridge, MA  02138

617-496-8285 (office)
617-495-8013 (fax)

=0CFrom: "Peacy, William" 
Date: April 7, 2009 10:23:41 AM EDT (CA)
Subject: RE: [DCHAS-L] Class lab fume hoods?

We just opened our dedicated new Health and Science Building and it  
will open this summer. The design has the general and organic chem  
working in the hoods. The gen chem works in pairs and org is  
individual. GOB and liberal arts chems still work on the benchtops  
with some hoods available. When you design the labs, the hoods will be  

one of the most expensive, if not the most expensive part of the design.

William "Bill" Peacy
Assistant Professor, Chemistry
College of DuPage, Rm. IC 3005b
425 Fawell Blvd.
Glen Ellyn, IL 60137
(630) 942-2486
Fax: (630) 942-2759

=0CFrom: "Carl Fictorie" 
Date: April 7, 2009 10:25:59 AM EDT (CA)
Subject: Re: [DCHAS-L] Class lab fume hoods?


We are about 8 years into a planning process for new chemistry and  
biology facilities, and we are planning for enough hoods in the  
chemistry labs for each student pair, in all of our labs.  We have  
made substantial use of Project Kaleidescope (,  
and you will find descriptions of a large number of projects on their  

site.  I can't think of any exceptions to the above rule in chemistry,  

although it is not followed as rigorously for biology, physics, or  
general science courses.

I've toured several new and renovated college facilities in our area  
(mainly NW Iowa), and all the projects have had at least one hood per  

pair.  My discussions with the engineering firm that we have been  
working with suggest that the trend will continue, and that the major  

question is energy efficiency and management.  As I understand it,  
building codes require that if a hood is present, it is supposed to  
run 24/7, although low flow settings are permissible.  Us academic  
types think that at night or over breaks when the lab is not in use we  

should be able to turn hoods off.

I would be interesting in hearing about any exceptions that you learn  

about with respect to this question.


Carl Fictorie, Ph.D.                                  email:  
Professor of Chemistry                               phone:   
Chemistry Department                                   fax 712-722-6336
Dordt College                            
498 4th Ave. NE
Sioux Center, IA 51250-1697

=0CFrom: "Samuella B. Sigmann" 
Date: April 7, 2009 11:14:39 AM EDT (CA)
Subject: Re: [DCHAS-L] Class lab fume hoods?

Hi Ralph - We have two teaching labs for the organic classes.  Each  
lab has 10 hoods.  With 2 students per hood, and one for reagents, the  

set up works well for 18 students.  I would definitely have a way to  
shut them down when labs were not running (for energy reasons).  We do  

not have that ability, so we are wasting a lot of energy.  Our  
building is 10 years old.

Don=92t always believe what you think.
Samuella B. Sigmann, NRCC-CHO
Lecturer/Safety Committee Chair
A. R. Smith Department of Chemistry
Appalachian State University
525 Rivers Street
Boone, NC   28608
Phone: 828 262 2755
Fax: 828 262 6558
Email: sigmannsb**At_Symbol_Here**

=0CFrom: Anne Skinner 
Date: April 7, 2009 12:13:46 PM EDT (CA)
Subject: Re: [DCHAS-L] Class lab fume hoods?

For what it is worth -- we have a ratio of one fume hood for 2  
students in organic chem, and one for 3 students in general chem.


  /O\  /O\  /O\  /O\  /O\  /O\  /O\  /O\  /O\  /O\  /O\  /O\  /O\  /O\
Si   Si   Si   Si   Si   Si   Si   Si   Si   Si   Si   Si   Si   Si   Si
  \O/  \O/  \O/  \O/  \O/  \O/  \O/  \O/  \O/  \O/  \O/  \O/  \O/  \O/

Dr. Anne Skinner
Chemistry Department, Williams College
47 Lab Campus Drive
Williamstown, MA 01267

Phone:  (413) 597-2285
Fax No: (413) 597-4116

=0CFrom: "Yaeger, Mary Ann" 
Date: April 7, 2009 1:56:29 PM EDT (CA)
Subject: RE: [DCHAS-L] Class lab fume hoods?

In our Organic labs we currently have bench top hoods for each student  

pair, as well as two larger hoods in each lab.  We are having one lab  

updated over the summer and installing island workbenches.  One hood  
will hang over each island and be accessible from all sides so that  
two pairs can work under it.  Then we will have 3 larger hoods with  
sashes in the lab also, and one will be handicap accessible.


MaryAnn Yaeger
Supervisor of Laboratory Services, CHO
Wesley College
120 N. State Street
Dover, DE 19901
phone (302) 736-2389
Fax (302) 736-2301


=0CFrom: "David C. Finster" 
Date: April 7, 2009 3:39:10 PM EDT (CA)
Subject: RE: [DCHAS-L] Class lab fume hoods?

I can relate our experience, (the underlying wisdom of which is open  
to scrutiny.)

We built new introductory and organic chemistry labs four years ago.   

In the organic labs we have 8-foot hoods with double sashes; each  
student gets 4 feet of lab space.  This has worked out well.  All of  
the hoods are located on walls in order to avoid having hoods in the  
"middle of labs" which destroy sight lines (which is a safety issue,  
in our judgment).   The "all hoods on walls" is an architectural  
challenge, especially if windows are desired for aesthetic reasons.   
We managed, successfully, we think.

In our introductory labs I did careful assessment of our year's worth  

of experiments and determined that having students work in fume hoods  

was actually rather uncommon.  Thus, we opted for eight 6-foot hoods  
in labs designed for 32 students.  Students always work in, at least,  

pairs and we are moving toward more group/cooperative experiments with  

4 or even 8 students per group (with various assigned tasks.)  Since  
the experiments that do require work inside hoods are not particularly  

space-intensive it has been possible to have two pairs of students  
work in a single 6-foot hood without problems.  (Four students would  
never actually be trying to perform manipulations in a single hood at  

a given moment in time.)  The duty cycle on this configuration is low  

and has seemed a very reasonable situation.

As more Green Chemistry experiments enter the curriculum, the needs  
for hoods may decrease.  The point of this comment is not to predict  
the disappearance of hoods (!!) but to suggest that given the capital  

and maintenance costs of hoods, it is best to have as few as possible  

so long as safety is not compromised.  In organic labs, hoods are  
obviously required, and likely so for every experiment performed.  For  

us, in introductory chemistry labs we chose to have "enough" hoods to  

allow all students access to a hood (perhaps with the level of  
"crowding" that would be unacceptable on a weekly basis) when the  
chemistry demanded hood use, but we traded this off against the use of  

the space for other purposes (as well as recognizing the capital and  
maintenance costs of hoods).

The "three hoods for 18 students" might be OK, depending upon duty  
cycle and other nuances.  Even during a given lab, it may be possible  

to stagger the need for using hoods if the hood is needed for only a  
short period of time.   I think it would be pretty hard to determine  
the correction student-to-hood ratio without understanding the details  

of a particular lab curriculum.  Of course, under-engineering a lab  
with regard to some future, desired curriculum would be unfortunate.    

Since the hoods will also be the source of room air changes/hour, this  

need to taken into consideration.


David C. Finster
Professor, Department of Chemistry
University Chemical Hygiene Officer
Wittenberg University

=0CFrom: "Tan Khai Seng" 
Date: April 7, 2009 8:40:38 PM EDT (CA)
Subject: RE: [DCHAS-L] Class lab fume hoods?

Hi Ralph

Greetings from Singapore.

I'm not sure if anyone replied to your posting. Here's some of our  
experiences with fumehoods for teaching lab.

We have renovated our teaching labs, particularly our synthesis  
teaching lab back in 2003. We have moved from the open bench with some  

shared fumehoods to a full fumehood design. Every student has a 1m  
basic fumehood known as the school fumehood. Common chemicals and  
other setups for the lab are located in larger fumehood by the side of  

the lab. i have attached a picture of the lab. We are quite happy with  

the performance of the fumehood and we are likely to stick to such  
design in any future lab design.

with this design, there is no sharing of fumehood. we don't have to  
worry about students performing incompatitible work. In the event of  
any screwups which we have see a fair number, any spillage will be  
contained within each fumehood. This also allow for a wider range of  
experiments to be performed in the lab since everyone have their own  
fumehood. Due to space shortage, we have tried running 2 different lab  

classes in the lab without much problem.

However this design will not be energy efficient. The fumehoods are  
basic constant air velocity fumehood, each cluster of fumehoods are  
linked to a common extractor fan, thus the whole cluster will be turn  

on in order to use one. this will be a headache with HVAC. as far as  
i'm aware, for another university in singapore which i was involved in  

the design, they were eventually forced to reduce the face velocity to  

reduce the energy cost.

Just let me know if you need more information.

I'll be happy to share with you our experience.


=0CFrom: "Klotz, Ann" 
Date: April 7, 2009 9:18:58 PM EDT (CA)
Subject: Re: [DCHAS-L] Class lab fume hoods?

Our classroom laboratory enrollment is 16 students.  The chemistry  
classroom laboratories have nine hoods with one used for each pair of  

students and one used for dispensing volatile reagents and waste.

The building is 7 years old.  With more emphasis on student projects,  

I find that the hoods are almost always in use.

Ann Klotz
School of Science
Siena College
515 Loudon Road
Loudonville, NY 12211-1462

Office Phone: 518-783-2402
Cell Phone 518-860-8489
Siena College is a learning community advancing the ideals of a  
liberal arts education, rooted in its identity as a Franciscan and  
Catholic institution.

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