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co death - true or false? was re. kinder,

updated sat 27 nov 99 on fri 26 nov 99

> ---------- Forwarded message ----------
> Date: Wed, 24 Nov 1999 08:52:24 EST
> From: Ray Aldridge
> Reply-To: Ceramic Arts Discussion List
> Subject: Re: CO death - true or false? WAS Re. kinder,
> kiln room/...
> Resent-Subject: Re: CO death - true or false? WAS Re. kinder,
> gentler kiln room/...
----------------------------Original message----------------------------
> But in spite of my embarassment at having been proven wrong in so tragic a
> manner, I'll persist in my folly, to this extent: The original post was
> not limited to the possibility of a fuel burner producing CO. Had that
> been the case, I'd have agreed that this was a realistic possibility-- and
> as I mentioned, a reasonable precaution would be to have a CO alarm in the
> kiln room. But as the original statement is written, a less-experienced
> person might actually think that the little hobby electric kiln they have
> out in the garage posed a real danger that a person working in the garage
> might be felled "BEFORE your nose tells you to get out."
> I think this is an unrealistic warning. It's possible that a person could
> put something in such a kiln that would be potentially fatal to breathe,
> but I can't think of anything like that that would be odorless-- as CO is.
> Maybe Monona will straighten me out.

If you mean "acutely fatal" you may be right. I can think of chemicals that
can do this, but non of these would have any reason to be in the kiln. The
thing that saves us with regular firings is that the temperatures at which CO
come off the kiln over lap the temperatures at which smelly sulfur oxides and
aldehydes are also released.

But you should also consider that "chronic" potentially "fatal" metal fumes
usually have no odor: lead, cadmium, chrome, nickel, and the other
> I certainly shouldn't have made light of the possibility of CO poisoning in
> a kiln room, and I'm glad you corrected me. <

I worry about the suggestion to use a CO "alarm." If you buy the type that
only alarms, you may be seriously mislead. Repeated doses of CO far lower
than those that would set off a CO-detector can cause heart attacks in people
with certain heart problems and can damage the fetus if the Mother is
exposed. I especially worry about kiln in senior centers, classes for older
people, or classes for children with heart problems.

To explain when to worry: EPA has set their 8-hour limits for CO at:

12 ppm = unhealthy for sensitive groups (e.g. people with heart disease)
15 ppm = unhealthy for everyone
30 ppm = very unhealthy
40-45 ppm = hazardous

The CO alarms don't go off until:

100 ppm has been attained for 90 minutes; or
200 ppm has been attained for more than 35 minutes; or
400 ppm has been attained for more than 15 minutes.

In other words, the alarms will save your life only if you are damn healthy.

I suggest you get a CO detector of the type that will read out the highest
reading in the last 8 hours. Unfortunately, the highest reading they will
report is 30 or 35 ppm! But at least that is a start.

Schools with serious ceramics programs should purchase one of the expensive
continuous CO monitors for the kiln room.

Monona Rossol
181 Thompson St., # 23
NYC NY 10012-2586 212/777-0062