Date: Mon, 12 Apr 2010 13:28:56 -0400
Reply-To: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: Fred Simmons <fred.simmons**At_Symbol_Here**SRS.GOV>
Subject: Re: Flammable storage in Walk-in Refrigerator
In-Reply-To: <SNT105-W368B7DD9D7F9BCCD8581C0FC120**At_Symbol_Here**phx.gbl>
There are specific requirements in the NFPA codes:

Standard on Fire Protection for Laboratories
Using Chemicals
2004 Edition

A. The use of domestic refrigerators for the storage
of typical laboratory solvents presents a significant hazard to
the laboratory work area. Refrigerator temperatures are almost
universally higher than the flash points of the flammable
liquids most often stored in them. In addition to vapor accumulation,
a domestic refrigerator contains readily available ignition
sources, such as thermostats, light switches, and heater
strips, all within or exposed to the refrigerated storage compartment.
Furthermore, the compressor and its circuits are
typically located at the bottom of the unit, where vapors from
flammable liquid spills or leaks could easily accumulate.
Although not considered optimum protection, it is possible
to modify domestic refrigerators to achieve some degree
of protection. However, the modification process can be applied
only to manual defrost refrigerators; the self-defrosting
models cannot be successfully modified to provide even minimum
safeguards against vapor ignition. The minimum procedures
for modification include the following:
(1) Relocation of manual temperature controls to the exterior
of the storage compartment, sealing all points where
capillary tubing or wiring formerly entered the storage
(2) Removal of light switches and light assemblies and sealing
of all resulting openings
(3) Replacement of positive mechanical door latches with
magnetic door gaskets
Regardless of the approach used (explosion proof,
"laboratory-safe," modified domestic, or unmodified domestic),
every laboratory refrigerator should be clearly
marked to indicate whether or not it is safe for storage of
flammable materials. Internal laboratory procedures should
ensure that laboratory refrigerators are being properly used.

NFPA 45 also refers to NFPA 70 - National Electrical Code

If this is like most of these I've seen it has lights in it that are not 
explosion proof and sits near a potential ignition source if the vapors 
collect and come out when the door is opened.

Fred Simmons
Savannah River Nuclear Solutions

From:   Paul Sonnenfeld 
To:     DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Date:   04/12/2010 01:16 PM
Subject:        Re: [DCHAS-L] Flammable storage in Walk-in Refrigerator
Sent by:        DCHAS-L Discussion List 

May I suggest reviewing Chapters 27 and 34 of the International Fire Code 
(read-only versions are available from several sites).  Perhaps a visit 
from your local fire prevention officer would be appropriate.  Your 
collaborator needs to remember that when the fire department responds to 
the incident at his/her lab, he/she will have to provide some answers.  If 
you work for a private-sector employer who is not self-insured, I'd also 
suggest reviewing your fire and general liability insurance policies for 
specific language.

Unfortunately, it sounds like your collaborator has become complacent.

Respectfully yours,
Paul Sonnenfeld, CPEA 

Date: Mon, 12 Apr 2010 10:33:03 -0500
From: rlustwerk**At_Symbol_Here**VERIZON.NET
Subject: [DCHAS-L] Flammable storage in Walk-in Refrigerator
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU

Hello All,
I have a collaborator who is storing organic peroxides, solid and liquid, 
in a walk-in refrigerator/freezer.  They have done so for a number of 
years.  One of the new organic peroxides is a liquid with a low flashpoint 
(class IB flammable liquid).  At our facility, any flammable liquids that 
require refrigeration are stored in flammable-safe refrigerators.  I have 
seen the walk-in refrigerator in question on a previous occasion and was 
not impressed by the housekeeping--spills on the floor that had not been 
cleaned up, poor organization and poor lighting.  I do not have 
juristiction over this space, but want to offer advice that pertains 
specifically to walk-in size refrigerators or cold rooms.  I'm sure that 
one of the arguments that this collaborator will present is that the 
walk-in is large enough to offer sufficient dilution to prevent an LEL 
from developing.  Any regulations, stories, advice or help would be 
wonderful.  In addition, how does one address the issues that these 
materials are both flammable and oxidizers, when there may be storage with 
other flammable liquids--should there be entirely separate storage?
Rigel Lustwerk

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