DCHAS-L Discussion List Archive

Because our institutions are in Texas, the bulwark of fire/life safety 
regulation burden comes from the NFPA codes because that's what the 
State Fire Marshall has established.

First thing first, I would start with NFPA 101. Do any of the rooms have 
an occupancy load greater than 49 people? If yes, then we need two 
exits. Is the distance from the remotest part of the occupancy to the 
place where there are two different paths out of the building greater 
than 75 feet (unsprinklered) or 100 feet (sprinklered)? If yes, then we 
need two exits. There are some other rules stipulating dead-end 
corridors and total exit width by floor and section of floor. But the 
general idea is that we start with 101 first.

Now we can get into NFPA 45. 

Next, we need to identify the hazard class of each lab as defined by 
4.2.1.1 using tables 10.1.1 and 10.1.5 as guidance. The hazard class of 
the lab will be the main driving force in determining that specific 
lab's egress standard and how much flammable liquid you can store. 

What kind of fire separation do the labs have? If you have an "A" lab, 
but that lab lacks fire separation, you'll have to start removing 
flammables from that lab until the class decreases. But even then, EACH 
"D" lab can possess 1 gal of flammables out in the open for every 100 
sqr. ft. of lab space (Even class 1a), if the flammables are stored in 
flammable cabinets then that amount doubles! 

But there's a catch...is the lab used for instructional or educational 
purposes? If so, then there are restrictions in 4.2.2.Insturcional labs 
can only be a hazard class of C or D, and an instructional lab must 
either be a "D" hazard class OR possess 50% of the flammable volume of a 
class "C" laboratory.    

Now that we have ascertained our hazard classes we can proceed with the 
lab egress issues spelled out in 5.4. A second exit is needed when:
(1)      A laboratory work area contains an explosion hazard located so 
that an incident would block escape from or access to the laboratory 
work area. 
(2)      A laboratory work area within a Class A laboratory unit exceeds 
46.5 m2 (500 ft2). 
(3)      A laboratory work area within a Class B, Class C, or Class D 
laboratory unit exceeds 93 m2 (1000 ft2). 
(4)      A hood in a laboratory work area is located adjacent to the 
primary means of exit access. 
(5)      A compressed gas cylinder larger than lecture bottle size 
[approximately 5 cm  33 cm (2 in.  13 in.)] located such that it could 
prevent safe egress in the event of accidental release of cylinder 
contents. 
(6)      A cryogenic container located such that it could prevent safe 
egress in the event of accidental release of container contents.      

"Explosion hazard"? 4.3.2 leads much to the imagination. It doesn't 
really say who gets the final say in determining explosion hazards. To 
quote a coworker of mine: " Who determines? The local fire code 
official? The faculty member trying to implement the protocol? The poor 
bastard who gets hit by shrapnel? Or the poorer bastard who has to 
process the insurance claim?

Limiting flammables for the whole building to 1 gallon for each chemical 
is overkill. You can have a 400 sqr. ft. class "A" lab with nearly 120 
gallons of flammable liquids and still not need a 2nd exit provided NFPA 
101 concerns are ok. 

BTW I'm a big fan of UMHB, I met my wife on that campus.

Luke Leppla
=A0
Safety Technician I
EHSRM
One UTSA Circle
San Antonio TX. 78249
Ph. (210) 458-6697
=A0
=A0
=A0

    

-----Original Message-----
From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**list.uvm.edu] On Behalf Of 
Murphy, Dr. Ruth Ann
Sent: Wednesday, May 21, 2008 2:05 PM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: [DCHAS-L] Fire Code for Lab

My question is about exit requirements for chemistry labs.  Does a
policy limiting the amount of each flammable substance to one gallon or
less  in the entire building allow  exits from different  upstairs labs
to lead to only one hallway?   In other words, students from various
labs would have to exit by the same hallway, and there would be no limit
as to the number of flammable chemicals allowed - as long as each one
was present in amounts less than one gallon.  Natural gas lines would
also be in the labs.

 

Thank you for any help you can provide.

 

Ruth Ann 

 

Ruth Ann Murphy, Ph.D.

Chairperson

Department of Chemistry, Environmental Science and Geology

The University of Mary Hardin-Baylor

Belton, TX  76513-2599

254.295.4542