Word of Warning--Carbon Monoxide

[Dave Richards]

I just got off the phone with my brother. He told me a little story I thought would be good to pass on.

He has a large one-car-sized shop. He has been using a kerosene fired torpedo heater until he can get gas run for ceiling mounted unit. Because of the kerosene heater he installed a CO detector. He's never seen the detector go above 0 even when he has been running the heater on and off all day unitl the other day when he was removing shellac from a couple of teak doors he's refinishing using denatured alchohol. He said he happened to look up at the detector and saw it display 32. Shortly after that it jumped to 50 and the alarm tripped. He got out and opened up the shop to air it out.

Evidently the kerosene heater was burning the fumes of the alchohol and generating CO in the process.

I figure it's a good lesson. The fuel your open flame heater burns for heat may not create carbon monoxide but the fumes from a solvent or finish you may be using might when it gets burned.

Fortunately my brother had the detector in his shop. I'd hate to think of the result if he hadn't. Might be a good idea for all of us to have one. At least if you've got an open flame heater.

[Brad Olson]

IIRC, Ethanol (the alcohol used as a solven for shelac) interferes with CO detection and will set off a CO alarm. There wasn't extra CO being produced (ethanol is clean burning, and only burns to CO2-carbon dioxide, nont monoxide, plus H2O), it was the elevated level of alchol vapors from the shellac. I think CO detectors go off with PPB (parts per billion) levels of CO, something easy to achieve finishing with shellac.

[Dave Richards]

Thanks for that Brad. Still I guess it is good to be careful, huh?

[Brad Knabel]

Am I being overly cautious in thinking that it's probably not a good idea to be doing finishing with a flammable liquid around a portable heater?

[Dave Richards]

Technically he wasn't doing finishing but yes, you're right. On the other hand he was working as far away from the heater as possible.

Still, my point was that it would be a good idea to have a CO detector in the shop.

[Brad Olson]

Technically he wasn't doing finishing but yes, you're right. On the other hand he was working as far away from the heater as possible.

Still, my point was that it would be a good idea to have a CO detector in the shop.
YES, that point is a good point, especially with a kerosene or propane heater!

I wasn't trying to minimize risk, just to let you know why it was screaming so quickly.

[Dave Richards]

Brad Olson, I appreciate you identifying the fact that the ethanol interferes with the CO detector.

The reply you quoted was more directed at Brad Knabel's post regarding safety of working with flammables around a portable heater.

My brother was as un-around the heater as he could be while still getting to enjoy the heat.

I suspect that sort of thing happens more than anyone would like to think.