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Trying To Escape The Smoke? Try A Corsi Box

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Weather forecasters say smoke and haze are in the forecast this weekend in parts of the Inland Northwest.

One air quality regulator in north Idaho says it won’t be the last time we see smoke this summer and he urges people to get ready for it.Dan Smith from the Idaho Department of Environmental Quality monitors the air in Coeur d’Alene and the Silver Valley. When that air is bad, Smith hopes you’ll be ready to protect yourself, inside and out.

If you’re outdoors, he recommends you wear an N-95 or P-100 mask. As with masks to protect yourself from Covid, Smith says you need one that fits tightly over your nose and mouth. The blue surgical masks won’t protect you from smoke, he says.

If you’re in your car, he says, put the air on re-circulate so you’re not bringing in outside air.

“Staying inside is a good way to go. The problem with that is your air comes from outside. You’re relying on your furnace and air conditioner to filter the air. We do recommend that people change their air filter to the highest rated filter that they can get," Smith said.

But he says the best filters put a real strain on furnaces, especially those that aren’t considered high-efficiency furnaces.

He says you can buy extra filters that won’t tax your heating and cooling system, but those can be pricey.

“So I was looking online the other day and found what’s called a Corsi box. C-O-R-S-I. It’s a series of five Merv 13 filters, 20-inch filters, taped together with a 20-inch box fan on top of it. The total cost, if you were buying everything brand new, is about $90," he said.

You do have to assemble the box yourself, but you can see what it looks like if you Google "Corsi boxes." Smith says they compare favorably with some of those more expensive options.