about CO, #039 and the rest

LEAD PIPE

Larry, this is a bit off topic but I am trying to find out the OSHA standard for CO in the work place I keep coming up with 2 different numbers 50 ppm and 35 ppm for 8 hours. Do you know which one is the correct number?
Thanks
John

Larry (from OSHA)

some thoughts from a slightly different slant

I'm not in your profession. I don't know squat about combustion. I do know a little about accidents and causes.

I think the main goal for all of you is to provide safe systems that have a low likelihood of causing injury, illness, or death.

When I investigate injuries in factories, I almost always find a collection of things that went wrong that led up to someone getting hurt or killed.

As an example, I deal with punch presses a lot. The regulations are extensive. When you look at the machine in a wholistic approach, you find that there are several areas that need to be dealt with to be safe. Things like basic machine construction, safeguarding the point of operation properly, procedures for setup, regular inspections, competence of maintenance people, and training of operators. Lots of things to deal with.

I look at it like a pie with all the issues as slices. Take out one piece and the likelihood of injury goes up. Take out more and more pieces until you get to a critical mass and an injury will occur. Guaranteed.

The point is that if you are going to do responsible work for homeowners, it makes sense to cover all the bases. Manufactures provide the specifications, technicians ensure that they are met.

But, on the other hand, back to the pie. Yes, if you don't test, you don't know. Will this alone cause a catastrophe? Most likely not, but if a racoon decides that this chimney is where he wants to be, now what. I am guessing that for many of the CO tragedies posted here, there was a combination of events that led up to the resultant death or illness.

I know pretty much how many slices of the pie you can remove before you lose a hand on a press. But does it take two things going wrong on a boiler or three or which combination of events before CO starts spilling into the building?

So, from where I sit, and again, I don't know very much about combustion, I would think that by ensuring that CO is as low as practical, that would provide a greater margin of safety in case the flue becomes blocked or falls off.

Put all the pieces of the pie in place and the chance of a negative outcome is reduced.

Just some random thoughts from someone outside your industry.

Larry (from OSHA)

Murph'_5

Thanks Larry

For sticking it out and hanging with us!!

Larry (from OSHA)

workplace CO levels

John,

Both numbers are correct. It just depends on where you are. The federal level is 50 ppm over 8 hours. Here in Minnesota and in some other state OSHA states, the level is 35 ppm. Also, there is a ceiling limit of 200 ppm in 15 minutes for federal and 200 ppm in 5 minutes here in Minnesota. To confuse it even more, in Minnesota, we have a level of 50 ppm if you are dealing with construction activities.

Hope this helps.

Larry

LEAD PIPE

I see

Thanks for the info.

Glenn Harrison_2

Larry, isn't there another standard of...

9 or 10 ppm continuous exposure, as in over 8 hours?

Larry (from OSHA)

Glenn

The Clean Air Act last ammended in 1990 required the EPA to create National Ambient Air Quality Standards. They came up with 9 ppm for CO over an 8 hour period and 35 ppm for 1 hour. Both levels are not to be exceeded more than once per year. Those levels were apparently set to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly. (source: EPA web site)

Personally, if my CO meter that I wear for my protection showed 9 ppm outside, I think I'd want to be in a different part of town! I'm guessing that you might find levels more than zero if you are near a steel mill or large foundry.

Hope that helps and my appreciation to Dan, the Wall, and everyone who posts.

Larry

Glenn Harrison_2

Thanks Larry

I knew I heard those numbers before, I just thought they applied to indoor exposure. Although I personally would be doing something if I found 10 ppm indoors anywhere, and like you said, if I picked up 10 outside it would be road trip time.