I had commented earlier about ASTM committee F23. Let me be more specific.
F23.8 is the subcommittee that has responsibility for flame and thermal
resistance protective clothing. They publish standards and guides on
thermal and flame resistance as well as care and laundering of protective
I feel that I need to add a bit more to this conversation. There are two
issues. First is flame resistance. Second is thermal resistance (or
insulation value). Nomex is fantastic for the first category but not the
second. It provides protection against flash and flame but not insulation
against heat (hence the reason why fire fighters gear is multilayered and
includes a vapor barrier).
Nomex is excellent against a sudden blast (as in arc flash), but may not be
the best choice for an incidental fire (not prolonged). Work in a
petrochemical plant and work in a laboratory are not equivalent in any
Wool and some other natural fibers actually offer more protection since they
char and absorb the energy. This is a theoretical consideration; however,
the key point is that polyester of any type should not be worn as it will
melt under high thermal loads and increase the burn severity.
There is more to consider than simply always wearing a very uncomfortable
inherently flame and flash resistant lab coat WITH proper clothing and
undergarments. As normal, a little research and a risk assessment should be
S.Z. Mansdorf, PhD, CIH, CSP, QEP
7184 Via Palomar
Boca Raton, FL 33433
From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of
Sent: Tuesday, July 22, 2014 3:28 PM
Subject: Re: [DCHAS-L] Use of fire resistant lab coat
My comments reflect my industrial background. The discussion on this
question has been very good. Contributors have pointed out the distinction
between fire resistant lab coats that have been treated with a fire
resistant chemical (there has been some controversy about how well such
chemicals work, but that's another question) and Nomex which is a material
that itself is fire resistant.
One important issue that has been mentioned by others is the process of how
(if they are) the lab coats are cleaned. The service provider that does
this must know how to clean lab coats. It has been mentioned that cleaning
treated lab coats will remove some of the flame resistant chemical, thus
decreasing the effectiveness of the coat's flame resistance. If flame
resistant lab coats, treated or Nomex, are washed or dried with other
materials, fibers from those other materials can become embedded in the lab
coat, reducing its flame resistance. If your strategy might be to include
lab coats with other items you send out for laundering, or if you are
thinking of allowing students to wash their lab coats on their own (not a
good idea on fundamental principals of lab safety), the problem of
combustible fibers embedded in the lab coats can be significant.
Regarding Nomex coats, these are often required at refineries, at least in
areas where exposure to flammable materials is possible. My colleagues
working in Nalco's Energy Services Group routinely had to wear them when
visiting refineries. Their continuing concern about Nomex is that such
coats are heavy and uncomfortable to wear. These lab coats are "hot in the
summer and cold in the winter." The fact that it was company policy to wear
them whenever required at a company site or a customer site meant that
compliance was required. But my colleagues often mentioned the discomfort
as the first part of any discussion about Nomex as a fire protection piece
of equipment. I would recommend against requiring anyone to wear a Nomex
coat unless the hazards of the job or the location require it.
Repeating the comments made by others in this discussion, design your lab
coat policy to match your hazards. If your students do not work with
flammable materials, then the lab coat does not need to be flame resistant.
For students working with flammable materials or in labs where others might
be working with flammable materials, you might establish a different policy.
With respect to graduate students, postdocs, and permanent lab staff who all
may use flammable materials some of the time, it is reasonable to require
them to own more than one type of lab coat. We use different gloves for
different hazards; we can do the same for lab coats.
One final comment of a somewhat nitpicking nature. If I understand the
circumstances correctly, the reason Cal/OSHA focused on lab coats as
necessary PPE for protection when working with flammable, especially
pyrophoric, materials was that Ms. Sangji was wearing a polyester top that
presumably would catch fire readily, increasing the extent and severity of
her injuries. Lab coats made from less combustible or non-combustible
materials would provide a barrier of prevention to the worker. My concern
is that sometime in the future, some of our purchasing agents are going to
substitute 100% polyester lab coats in their purchasing agreements with
suppliers, because they will be cheaper than the lab coats currently in use.
Wearing a polyester lab coat over a polyester top does not significant
diminish the hazard for someone working with pyrophoric materials.
From: Ralph B. Stuart
Sent: Friday, July 18, 2014 11:23 AM
Subject: [DCHAS-L] Use of fire resistant lab coat
A question I'm wondering about as we as a professional community consider
the aftermath of the UCLA lab fire and its legal follow up is whether there
is a reason beyond finances to not use fire resistant lab coats in the lab
setting. I recognize that both the initial and maintenance costs associated
with fire resistant coats are significantly higher than alternatives, but I
wonder if there are other disadvantages associated with their use.
Thanks for any information about this.
Ralph Stuart, CIH CCHO
Chemical Hygiene Officer
Department of Environmental Health and Safety Cornell University Ithaca, NY
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