Main Difference between BS 476: part 4 and EN ISO 1182
Building Materials Non-combustibility Test
Many customers have different requirements for the test standards of Non-combustibility testers. Our Non-combustibility tester can be customized according to the needs of customers. It can meet the British standard BS 476 part4, and can also meet the international standard EN ISO 1182. Let's distinguish between these two standards. What is the difference?
Test category: fire test, non-combustibility test of building materials
The main differences are distinguished from the following six aspects, namely the sample size of the non-combustibility tester, state adjustment, number of thermocouples, furnace temperature stability requirements, test completion judgment conditions and standards for non-combustible materials conformity assessment criteria.
1. Sample size requirements
BS 476:part 4: Length and width are 40+0/-2mm, height 50±3mm, volume 80.0±5.0cm3.
EN ISO 1182: The diameter is 45+0/-2mm, the height is 50±3mm, and the volume is 76±8cm3.
2. Condition adjustment requirements
BS 476:part 4: 60±5℃ ventilated drying oven for 24h
EN ISO 1182: 60±5℃ ventilated drying box, adjust 20h to 24h
3. The number of thermocouples required
BS 476:part 4: 2 pieces (sample center, inside the furnace)
EN ISO 1182: 3 pieces (sample center, furnace, sample surface)
4. Furnace temperature stability requirements
BS 476:part 4: The temperature in the furnace should be stable at 750±10℃ for at least 10 minutes.
EN ISO 1182: The average temperature in the furnace is stable at 750±5℃ for at least 10 minutes. Its temperature drift (linear attenuation) should not exceed 2℃ within 10min, and the maximum temperature difference from the average temperature within 10min should not exceed 10℃
5. Judgment conditions for test completion
BS 476:part 4: 20 minutes
EN ISO 1182: When the temperature measured by all thermocouples does not change more than 2°C within 10 minutes within 30 minutes, it is considered that the final temperature equilibrium has been reached and the test will stop. If the temperature obtained by the thermocouple does not reach the final temperature equilibrium within 30 minutes, the test should be continued; at the same time, the final temperature equilibrium should be checked every 5 minutes. When the thermocouple reaches the final temperature equilibrium or the test has been conducted for 60 minutes, stop the test and record the duration of the test. Then, take out the sample from the furnace. The end of the last 5min interval or 60min is the end of this test.
6. Conformity assessment criteria for non-combustible materials
BS 476:part 4: The temperature rise of the highest temperature in the center of the test piece relative to the initial furnace temperature is ≤50℃, and the temperature rise of the highest temperature in the furnace relative to the initial furnace temperature is ≤50℃, and the flame duration is ≤10 s
EN ISO 1182: Class A1 (EN 13501-1:2007) The temperature rise of the highest temperature in the furnace relative to the final equilibrium temperature in the furnace △T≤30℃, and the mass loss △m≤50%, and the continuous flame time tf= 0 (No continuous combustion) Class A2 (EN 13501-1:2007) The temperature rise of the highest temperature in the furnace relative to the final equilibrium temperature in the furnace △T≤50℃, and the mass loss △m≤50%, and the continuous flame time tf ≤20 s