NFPA 276-2019 Standard Method of Fire Test for Determining the Heat Release Rate of Roofng Assemblies with Combustible Above-Deck Roofng Components

NFPA 276-2019 Standard Method of Fire Test for Determining the Heat Release Rate of Roofng Assemblies with Combustible Above-Deck Roofng Components. 7.1 Verifcation of Operation Using Blank Test Specimen. The operation of the furnace shall be verifed using the blank test specimen within a maximum of 5 days prior to testing being conducted. 7.2 Calibration Using Calibration Specimen. The furnace shall be calibrated at a minimum of every 90 days using the cali‐ bration test specimen. 7.3 Preheating. The test furnace shall be preheated with the blank test specimen in place, and the main burner fuel fow shall be adjusted to the required fow. 7.3.1 The supply air shall be initiated, and the temperature of the supply air shall be 100°F ± 5°F (38°C ± 3°C). 7.3.2 The fow rate of heptane shall be constant to the main burners until the temperature inside the furnace is 300°F (149°C) as measured by the thermocouples embedded in the refractory brick as described in 5.1.4. 7.3.3 The fuel fow to the main burners shall be shut off when the preheat temperature is reached. 7.3.4 The supply air shall continue to operate. 7.3.5 The blank test specimen shall then be removed. 7.3.6 The next specimen shall not be placed into position for testing until the thermocouples embedded in the refractory brick as described in 5.1.4 indicate 170°F ± 5°F (77°C ± 3°C). 7.4 Blank Specimen Test Procedure. The verifcation of the operation of the test furnace shall be conducted for 40 minutes with the blank test specimen placed in the specimen opening. 7.4.1 The test furnace shall be preheated as described in Section 7.3. 7.4.2 The blank test specimen shall be placed in the sample opening of the test furnace. 7.4.3 The average temperatures measured by the 12 thermo‐ couples located in the exhaust fue shall be recorded through‐ out the 40-minute test duration. 7.4.4 The temperatures shall be measured at intervals not exceeding 10 seconds during the test period. 7.4.5 Only the main burners shall be operated for the frst 30 minutes of the test. 7.4.6 The supply air shall be provided at a temperature of 100°F ± 5°F (38°C ± 3°C). 7.4.7 Airfow into the main burners shall be 763 ft 3 /min ± 76 ft 3 /min 7.4.16 The average temperature within the test furnace after the 10-minute exposure using the main burners and the auxili‐ ary burners shall be 1150°F...