The building I work at was evacuated on Tuesday and shut down on Wendnesday after about 20 people in one area got sick; they were dizzy and nauseated enough to be taken to hospitals.
The hazmat team from the fire department checked everything and came to the conclusion that it was nitrates and nitrites contaminating one of several hot water heaters in the building. Apparently the people in the area suppli ed by that heater used the hot water from the tap for cooking or making tea and cocoa drinks.
My first thought was that a gasket or seal gave out, allowing the water to contact the contaminants, but I can't see why a water heater would have lar ge amounts of nitrates and nitrites involved. Maybe someone on the group wi th experience in large-scale water heaters for an office building would kno w.
Someone in our department thought it might be a water softener system probl em; maybe someone grabbed a bag of fertilizer instead of rock salt for the flush and wash cycle, but we're on city water and water softeners are gener ally used with hard well water in my experience. Plus, would they have a so ftener servicing only the water heater and not the whole line, hot and cold ?
My wife, who watches a lot of Miss Marple type mysteries, thought it might be somebody trying to kill his girlfriend who works there, but contaminatin g a hot water heater seems a far fetched plot. He'd have to know which heat er served her break room area and get by the security desk in the lobby. Pl us, from what I know of water heaters, getting the contaminants into the he ater would not be easy.
Any thoughts? If we hear how it happened, I'll post an update.