Working on my third 100 liter batch using the GL one day process. I skimmed soap off the outdoor bubbled brew and I thought all the methanol was evaporated. Moved the batch indoors for the final filter and soap removal using a circulating pump,filters and a couple of muffin fans over the barrel. Could not smell any methanol near the barrel, only the sweet odor of fresh bio. In about 2 hours my basement carbon monoxide detector sounded off and displayed 87 PPM. Reset it but it continued to climb over 100ppm. Removed the brew to the outdoors and ventilated the basement for a couple of hours. Detector returned to zero. Display may not be accurate but considering I could not smell any methanol, maybe I stumbled onto a fume warning that may save someones health. If you have time could someone verify my findings and report back. Sorry I am busy at the time.

WDP

I've got one of those things unplugged in my garage...it was always going off and being fooled by grinding and welding vapors. I'll try to run a test over the weekend and report back.

Could be a good catch...

There are a number of "combustible gass" detectors that also detect methanol. They gennerally don't sound off until the methanol hits the Lower explosive level concentration. The minimum for safe exposure according to the federal government is 200ppm. That's a lot less than the LEL.

What brand and model of CO detector do you have?

It is a Nighthawk, plug in model with digital readout and memory. Just caught my attention as I couldn't smell any methanol while priming the pump.
Sometimes we all need a little help with the safety part of this hobby.

WDP

WDP -- I was looking at the Kidde web site. There are several models available including one that is a combo for detecting CO2 and Gas. Is this it?

http://www.kidde.com/utcfs/ws-384/Assets/900-0113%20Sheet.pdf

Chris

No, just a standard carbon monoxide detector, got it at Home Depot.

WDP

Pretty much verified the CO/methanol detector theory. My last batch (same as before) was left outside with the bubbler and a 20 inch box fan a few hours longer than before. Transfered inside for the final polish filtering with the small fans and not a single PPM shift on the detector. Readout may not be accurate, but an aid to check for alcohol contaminated air.

WDP

Methanol vapors are colorless and odorless. No wonder you didn't smell them. That doesn't mean there were no methanol vapors present.