Subject: Re: [DCHAS-L] Lab Safety Caps in Chem Labs
Date: Wed, 28 Aug 2013 21:28:00 +0000
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
Message-ID: 5E76EF51D002544DAC5CFA68490FC5DA33360595**At_Symbol_Here**
In-Reply-To <6911AC61A9F7B94F9F1558774853C66A13308C0E**At_Symbol_Here**HARDY.Bridgewater.local>

If you are seeing 100 sf per person recommendation, that would most likely include space other than the student’s lab, such as prep areas, stockrooms, offices for lab managers, equipment and chemical storage, etc.  24 students plus instructor would be 2500 sf, which is larger than my 4-bdr house. I was recently in a lab in which the architect took the 75 sf per person recommendation literally and there were 3 resin-top benches, each with drawers and space for 4 students per side.  The aisles between the benches were 10 feet wide, as was the aisle at the back.  The aisle at the front was 20 feet wide.  The room gave the impression of a couple of card tables set in the basketball gym.


We had discussions about changing enrollment caps on some of our labs several years ago.  Our enrollment caps are coded into our registration database and we cannot enroll more people in a room than allowed by the campus Fire Marshal.  He asked that I speak to the consultant for the International Building Code who wanted to know the number of square feet that was totally free and unobstructed by shelves, hoods, lab benches, racks for backpacks,  safety showers, chalkboard ledges – anything that might impede egress.  He also asked for the overall dimensions and perhaps asked about the presence of fire suppression sprinklers and the ratings of storage cabinets before he provided a recommendation.




Scott Goode, Professor

Department of Chemistry and Biochemistry

University of South Carolina

631 Sumter Street

Columbia SC 29208


Email:   Goode**At_Symbol_Here**

Phone: 803-777-2601

Fax:       803-777-9521


From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Joseph M. Crockett
Sent: Wednesday, August 28, 2013 7:51 AM
Subject: Re: [DCHAS-L] Lab Safety Caps in Chem Labs


Another factor should be the traffic flow. Our labs (general chem) would hold 19 (18 students and the professor) but we find that the flow of the room is better with only 16 students. This may be the effect of the furniture layout. For the organic labs we allow 100 sq ft per person - I've seen that number before but cannot reference it. Can someone give a reference?


Joe C


Joseph M Crockett

Professor of Chemistry and Chair

Bridgewater College

402 East College Street

Bridgewater, VA 22812


From: DCHAS-L Discussion List [dchas-l**At_Symbol_Here**] on behalf of Ben Ruekberg [bruekberg**At_Symbol_Here**CHM.URI.EDU]
Sent: Friday, August 23, 2013 6:23 AM
To: DCHAS-L**At_Symbol_Here**
Subject: Re: [DCHAS-L] Lab Safety Caps in Chem Labs

I have a question.  Given that the occupancy of a laboratory complies with whatever fire codes specify, would not an important question be “How many supervisory persons (TA’s and/or professors present) should there be per student?”


Thank you,




From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of James Saccardo
Sent: Thursday, August 22, 2013 2:41 PM
Subject: Re: [DCHAS-L] Lab Safety Caps in Chem Labs



In the NYC building code, it requires 50 sq. ft. per occupant in a lab and our labs are 1250 sq. ft. (Therefore 1200/50=24. At 1250 there is room for 1 instructor.). Consequently, there are 12 work stations, therefore students work at a station as a team of two. I would refer you to the NYC building code, Title 27, chapter 1, subchapter 6 (table 6-2; pp:166).


This link should get you pretty close:


This table shows 1 occupant/ 50 sq ft. for laboratories and 1/100 sq ft. for prep rooms.


Somewhere else in the code it is mentioned that furniture is taken into account or a standard 10% reduction in total sq footage is used.


Campus planning can tell you the sq footage. You should use their number. This is also a good legal justification for capping the class at 24. Check your local building code for lab occupancies.


Be Well,

James Saccardo, CHMM



From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of drsamples**At_Symbol_Here**COMCAST.NET
Sent: Thursday, August 22, 2013 12:31 PM
Subject: [DCHAS-L] Lab Safety Caps in Chem Labs


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


PS: Are you attending the CSI Breast Cancer Walkathon on Dolphin Day? Register Now>

Previous post   |  Top of Page   |   Next post

The content of this page reflects the personal opinion(s) of the author(s) only, not the American Chemical Society, ILPI, Safety Emporium, or any other party. Use of any information on this page is at the reader's own risk. Unauthorized reproduction of these materials is prohibited. Send questions/comments about the archive to
The maintenance and hosting of the DCHAS-L archive is provided through the generous support of Safety Emporium.