Greg Johnston

But because the smoke was being blown over the lake, CAER and the fire department saw no need to signal people to shelter in place, Greg Johnston, plant manager at Rohm and Haas Canada LP recalled this month.
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The company plant makes latex emulsions to use with latex paints and does work with acrylonitrile, a dangerous chemical which Johnston said has some of the properties of cyanide.

"We do point out we do use chemicals and chemicals can have an adverse effect," said Johnston, adding no matter how comprehensive a plant's safety procedures are, warning sirens are a sound practice, "our equivalent of a smoke detector for the community."

Neither siren is loud enough to be heard indoors; CAER says they're meant to warm people outside to get to shelter, then turn off the air conditioning or furnace and listen for announcements.

"You're much safer inside the house than outside," Johnston said.

Greg JohnstonPlant ManagerRohm and Haas Canada Inc.