The four commodities used in the tests were chosen to give different fire development and maximum heat release rates. Test 1 with wood pallets and plastic pallets had the highest total energy content and gave the highest maximum heat release rate. The large amount of combustible material also gave a longer period of elevated gas temperatures, with the highest maximum temperature of 1365º C.
The gas temperature near the ceiling in test 1 (at + 10 m) is compared to four different standard fire curves.
It can be seen that the increase in gas temperature in the test with wood pallets and plastic pallets (test 1) is very rapid and almost exactly follows the hydrocarbon-curve for about three minutes.
Then the temperature increases even further and more rapidly than the hydrocarbon-curve and instead follows the RWS curve, again almost exactly with exceptions for the fast time variations and for a period around 20 minutes after ignition where the measured temperature is higher than the RWS curve. The RWS curve was developed assuming a 50 m3 tanker fire with petrol or fuel oil lasting for 120 minutes and giving a heat release rate of 300 MW. The heat release rate in the tests in the Runehamar tunnel did not reach 300 MW, but still the temperature followed the RWS curve very well.
In test 4 only 3120 kg of cardboard boxes and polystyrene cups were used, potentially creating the lowest calorific energy output of all tests. However temperatures were recorded to be in the same magnitude of test 1, although for a shorter period of time.