Baking soda is an effective fire reduction method. However, flour and baking powder are very dangerous around flames. Flour is flammable and it can also conduct electricity. The combination can cause serious injury from electrical shock and worsen the situation by adding fuel to the fire. Baking powder is also not an option as it's also highly flammable. 

In some cases, you can use a fireplace once the insert has been removed. However, before burning a fire, you must have a professional inspect it and the chimney to make sure they're functioning properly and no damage has occurred from removing the insert. That’s because using a fireplace without an insert could create fire hazards due to issues with airflow and heat dispersion, depending on the fireplace design and material. A professional can advise on whether you should make certain repairs or modifications before using your fireplace as an open hearth.

You can’t gauge the lifetime of a fire door like you could, say, an engine. Fire doors should be checked at least once every six months to ensure there are no signs of degradation like leaks, holes, water damage, termite damage, or anything else that might compromise the functionality of the door’s fire resistance. Check your smoke detectors while you’re at it.

Depending on who’s doing the estimating, about 22,000 to 25,000 chimney fires happen each year in the United States. Given the fact that millions of Americans have fireplaces (and chimneys), that means chimney fires aren’t exactly common—but they’re not rare, either. Since they’re so dangerous, it’s important to take precautions to prevent them.