Had a seizure October 2013. No cause found. I remembered I was working on a boiler that day. I measured the Carbon monoxide level in that room this week. It was over 200 ppm in less than a minute. I worked in and out of that room all day the day of my seizure. I didn't seiz until after 3-4 hours, but was sick on the ride home. I was also sick from a severe cold all that week. The drive was from the mountains to the city, about a 3,000 foot drop in altitude.