Pilot spark energy in the cone calorimeter: a source of measurement uncertainties

This work presents measurements meant to study the influence of the spark energy on the time to ignition of a given material in the cone calorimeter. For this purpose, square slabs of particle board were tested under two radiation intensities until ignition occurred using two spark energies for each intensity level. Results show that increasing the spark energy leads to a reduction in the ignition time regardless of the radiation intensity. However, the influence of the spark energy on the time to ignition is, in absolute numbers, larger for the low radiation intensity case than for the high radiation intensity case. Nonetheless, the proportional difference is nearly 10% for both levels of heat radiation. Results from this work confirm that there is an influence of the spark energy on the time to ignition of a given material suggesting that a narrower and more specific definition of the ignition circuits allowed in the cone calorimeter would be highly beneficial for ensuring repeatable results among laboratories. Copyright (c) 2013 John Wiley & Sons, Ltd.