On Fri, 24 Dec 2004 07:17:52 -0600, email@example.com (m Ransley)
OH now thats just "choice". Ransley the Webtv boy putting out advice
Whats next Ransley? You going to teach someone how perform open heart
Stick to what you know best. Blowing jimmy boy.
I've got a couple of CO detectors, one for my old drafty house and one for the
old house I have next door. I have unvented heaters and was worried about CO
levels especially on cold days when the wind does not blow. It turned out I
never get a detection level. I was starting to worry if the things even worked
so I put a cigarette under one, and it went up to over 200 ppm. Just from the
smoke from the cigarette. I have a detached two car garage and put one out
there and messed around with the vehicles. With the doors to the garage
closed I started my car and it ran it up to around 700 then it actually
dropped when the catalytic converter got hot enough to start working. It
settled around 250 or so, but I had an old non catalytic car and it pegged it
to the limits of the meter 999 ppm very quickly, in less then 5 minutes so I'm
sure it was really much higher. Oh yea I cut the wires on the alarm so I could
play with it, without all the noise from the alarm. I tested the laundry room,
closed the doors and vented the natural gas dryer discharge into the room and
never got a detection level. What I found is natural gas in a properly
adjusted room heater puts out no CO and my house has plenty of fresh air to not
have to worry about O2 depletion even when the wind is not blowing. The one in
the house next doors went off when a heavy smoker was staying there because of
the CO from the cigarette smoking.
If mine read anything I'd be finding the source. A smoker in the house might
be enough under certain conditions, also an attached garage if the central
heater unit is picking up fumes from a car, or gas engine such as a lawnmower,
motorcycle, generator set etc. Mine read 0.0 all the time unless I
deliberately do something to cause a source of CO and that's with unvented
Several comments. NIOSH exposure level is 50 ppm (level at which worker can
be exposure to continuously) so 14 is not a problem by itself. I would
move the detector around the house to see what is the source. Check the
heated air from the furnace to see if there is a leak in the plenum. Take
the detector outside if not too cold and see what its zero level is. I
assume a gas stove will put out a small amount of CO since it vents into the
You know, Im almost shocked by some of the comments Im seeing posted
in here about CO. Im just going to assume that there is much unknown
advice to the average homeowner about CO?
You would have to be absolutely NUTS to knowingly expose yourself to
50ppm of CO continuously! Even 14PPM! Below is a level that may be
safe (009 PPM) but I still wouldnt knowingly expose myself to that or
any other level
ASHRAE 62-89 (American Society of Heating, Refrigeration and Air
009 PPM The maximum allowable concentration for continuous (24 hr)
exposure. ASHRAE states the ventilation air shall meet the out door
air standard referenced to EPA and 9 PPM.
You also, for the most part, cannot use a household CO detector to
detect a CO leak in a furnace plenum. The amount of air from the
blower in the furnace dilutes the CO so much that it takes a long time
and/or large concentration for your detector to register the CO.
Your assumption of a gas stove putting out CO is incorrect also. If it
is putting out CO it is burning poorly or it is causing incomplete
combustion. If it is, GET IT FIXED!
Dont rely wholy on your UL listed CO detector. Read the info. See what
kind of levels your detector alarms at. You might find it "alarming".
The Leader in Gas Detection Technology
GAS DETECTION NEWS - SUMMER 1996 - VOLUME #1
How Much Carbon Monoxide is Considered Safe?:
Standards which specify safe levels of CO in the home and workplace are the
subject of current debate. The Consumer Products Safety Commission (CPSC)
recommends against exposure to levels averaging greater than 15 ppm CO for
eight hours or 25 ppm for one hour. The National Institute for Occupational
Safety and Health has established an eight-hour average limit of 35 ppm CO and
a ceiling level of 200 ppm for workplace exposures, while the American Council
of Government Industrial Hygienists' guideline is an eight-hour average of 25
The U.S. Occupational Safety and Health Administration (OSHA) had established
an eight-hour average limit of 35 ppm CO and a 15 minute exposure ceiling of
200 ppm for workplace exposures under its 1989 air contaminants rule. However,
on July 7, 1992, the U.S. Court of Appeals vacated the air contaminants rule
because OSHA failed to establish that a significant risk existed for each of
the over 400 substances covered by the rule. The enforcement of those limits
was suspended starting March 23, 1993, and the CO standard reverted to the
pre-1989 eight-hour average limit of 50 ppm and a 15 minute exposure ceiling of
200 ppm for the workplace.
No they don't; those are eight hour legal limits. I doubt
that you'll find any expert that will say that even 1ppm is
good for you.
To jerk this flame-fest back to the original posting, any CO
detected indicates a problem. If your CO detector isn't bad
and is reading somewhat accurately, 14PPM indicates a dangerous
situation. Not only is something burning incompletely, but
whatever it is is leaking toxic gas into your living area. Get
it fixed right away.
I hope we don't get in a shouting match about this. There are a lot of
compromises about setting exposure limits, I speak from personal experience
having sat on committees that set these type of limits. Usually you have to
assume worst case. For example assume that you are setting a CO limit; you
need to consider one that is okay for someone who both smokes and has
restricted lung capacity. Physically CO ties up hemoglobin and prevents it
from carrying oxygen. Fortunately we have a lot of excess oxygen carrying
capacity so that loss of 10-20% oxygen carrying capacity is not noticed for
normal individuals. The exhaled breathe of smokers (after they have
finished smoking) is 5-10 ppm of CO. I still would recommend trying to
track down the source of CO or at least make sure it is not increasing with
I am not sure what the normal reading of a CO meter is in a house with
natural gas heat and stove should be in the winter -- anyone care to
On Sat, 25 Dec 2004 00:57:34 -0600, firstname.lastname@example.org (m Ransley)
Holy shit! Just when I thought you actually sat back and learned
something (Nornal Co should be Zero=0.) ........................
then all of a sudden you drift off into radiation exposure? WTF??
I know four people who are alive in spite of a bad CO leak because they
had an old drafty house. I was the only one who had symptoms, which
were rather intense. I persisted in trying to find an answer to why I
noticed what I noticed. When the owner got the gas company to come take
a look, they would not let residents back into the house without
correcting the problem - bad furnace.
I know another couple who were being gassed with CO in a new home
because it was sealed up very tight and the fireplace drew fumes back
into the house from gas appliances.
Nobody, ever, should be in a home with a suspected CO problem without
having it checked out. The gas company or the fire department should be
contacted right away. I would not stay in the home without checking it out.
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