Officials Warn of Spontaneous Combustion Risk of Linseed Oil and Other Common Household Products

— -- Summer is a popular time for home improvement projects, but officials are warning of a danger that many people may not be aware of until it’s too late: spontaneous combustion of common household products used to finish furniture and decks.

Oil-based wood stains and linseed oil can combust and burn even without any spark to initiate the fire, officials say.

Shannon Priddy’s Gaithersburg, Maryland, house was destroyed in 2014 after she says contractors left rags soaked in wood stain under her deck.

“We had no idea that anything like this could happen,” Priddy, who was not injured in the incident, told ABC News.

To demonstrate how easily this can happen, Montgomery County Fire and Rescue in Maryland teamed up with “GMA” on the Lookout to conduct an experiment. We put linseed oil on some rags and put them into a box and we waited.

Donnie Boyd, a Montgomery County fire inspector, explained just how combustion occurs when linseed oil is left on a cotton rag.

“It actually heats up as it dries. It's a chemical reaction,” he said. “So it spontaneously combusts once it reaches its ignition temperature.”

Two hours into the experiment, a probe recorded a temperature of 204 degrees inside the box, and after four and a half hours, smoke appeared. Nearly six hours into the experiment, the box was burning.

Boyd said ignorance of -- or disregard for -- the issue has contributed to many fires in Montgomery County. He urged everyone to carefully read the labels on products used to do housework and home improvement projects.

The label of the container used for the "GMA" on the Lookout experiment read, "CAUTION! CAN CAUSE SPONTANEOUS COMBUSTION. Boiled Linseed Oil generates heat as it dries, which can cause the spontaneous combustion of materials contacted by this product. Oily rags, waste, and other oily materials contacted by Boiled Linseed Oil can cause spontaneous combustion fires if not handled properly.”

Homeowners should also keep rags that have absorbed oils, such as linseed oil, in well-covered metal cans and make sure the rags are thoroughly dried before collection or transport.

It’s a message that Priddy hopes to spread.

“I would never want it to happen to anyone else,” she said.