At Interflam 2016, Jeong et al presented five full scale fire tests carried out on 97 x 196 cm spring-coil bed mattresses manufactured in Japan.
The mattresses were 23 cm deep, of which around 3 cm of foam (total top and bottom) and 17 cm of polyester cloth sheathed springs. The mattresses were fire tested placed on the floor and on steel frames of heights 12 – 52 cms. Peak Heat Release and speed of fire growth increased with the height above the floor. The mattresses at 32 and 52 cm height reached heat release of 1 700 kW, with flames spreading >1 m over the mattress, within 5 – 6 minutes after ignition. These results confirm the danger of non fire-safety treated mattresses including those based on metal springs.
“Analysis of heat release rate of bed mattress installed at different heights”, J-J. Jeong et al., Interflam 2016, Windsor UK, 4-6 July 2016, proceedings page 269 http://www.intersciencecomms.co.uk/html/conferences/Interflam/If16/if16%20Table%20of%20Contents.pdf