Interesting article in Angie's List Magazine 10/16, Fast Fires. According to research by Underwriters Laboratories three decades ago you had 17 minutes to get out of your house until the room turned to flashover (1,000 degrees), today you have 3 to 4 minutes.
The factors listed are 1. Furniture and Bedding. Then- a candle flame set to a cotton sofa required more than 10 minutes to consume the sofa and the fire reached flashover in 29 minutes and 30 seconds. Now- a candle flame set to a polyester sofa resulted in the room being consumed in 3 minutes and 40 seconds. Engineered Wood (wood chips and sawdust held together by glue) used in many components of home building , but primarily floor joists while cheaper and stronger than traditional lumber burns much faster. Then- a floor built from traditional lumber collapsed in 10 minutes and 35 seconds after ignition. Now-a floor built from engineered lumber collapsed in just 6 minutes under the same conditions. 3. Home Design with open floor plans, higher ceilings and fewer compartments encourage fire spread. Then-average size new single family home was 1,660 square feet. Now-2,392 feet. 4. Doors and Windows. Then-wood frame single-glazed used between 1950-1970 failed under fire averaged 9 minutes and 37 seconds. Now- modern vinyl-clad wood frame double -glazed failed in an average time of 4 minutes and 19 seconds. 5. Wall Linings Then-plaster and lath walls was breached in 74 minutes after ignition. Now- under the same circumstances gypsum drywall breached in 23 minutes and 30 seconds.
In a flashover an unprotected person has no chance of surviving. A firefighter in their protective gear has 30 seconds.
The factors listed are 1. Furniture and Bedding. Then- a candle flame set to a cotton sofa required more than 10 minutes to consume the sofa and the fire reached flashover in 29 minutes and 30 seconds. Now- a candle flame set to a polyester sofa resulted in the room being consumed in 3 minutes and 40 seconds. Engineered Wood (wood chips and sawdust held together by glue) used in many components of home building , but primarily floor joists while cheaper and stronger than traditional lumber burns much faster. Then- a floor built from traditional lumber collapsed in 10 minutes and 35 seconds after ignition. Now-a floor built from engineered lumber collapsed in just 6 minutes under the same conditions. 3. Home Design with open floor plans, higher ceilings and fewer compartments encourage fire spread. Then-average size new single family home was 1,660 square feet. Now-2,392 feet. 4. Doors and Windows. Then-wood frame single-glazed used between 1950-1970 failed under fire averaged 9 minutes and 37 seconds. Now- modern vinyl-clad wood frame double -glazed failed in an average time of 4 minutes and 19 seconds. 5. Wall Linings Then-plaster and lath walls was breached in 74 minutes after ignition. Now- under the same circumstances gypsum drywall breached in 23 minutes and 30 seconds.
In a flashover an unprotected person has no chance of surviving. A firefighter in their protective gear has 30 seconds.