Starting the car in an attached garage

A car running in the garage fills it with carbon monoxide. With the house attached, it doesn’t stay in the garage.

A garage at night, its door open partway. Inside, a car idles with its tail lights on and exhaust drifting across the floor, and a person walks toward the door into the house.

What is carbon monoxide?

A gas with no smell, taste or colour. You won’t notice it.
Don’t idle your car in the garage, even with the door open.
In an attached garage, it seeps into the house.

We tried it

We remote-started a car in a closed garage. Within half a minute our sensor read about 150 ppm, twice the level a home CO alarm is built to go off at. With the door open a quarter of the way, it started falling. At three quarters, it was almost gone.

What SafeGarage does

SafeGarage with CO opens the door a little when carbon monoxide rises while a car warms up on a winter morning. A ventilation helper, not a CO alarm: keep a certified alarm in the hallway outside the bedrooms.

What about security?

It doesn’t throw the door open. You choose how far, and a quarter of the way is enough to let the air out. Only if the carbon monoxide keeps climbing does it open the rest of the way, and your phone is told either way.