LFY-668 Wheelchair Seat Posture Support Device Flame Retardant Testing Instrument

Main purpose/Use 
This instrument is used to test the flame-retardant performance of the material assemblies of the body position support devices of wheelchair seats (such as seat surfaces, backrests, side supports, headrests, pelvic positioning belts, and trunk supports), after they have been subjected to a heat source equivalent to that of a smoldering cigarette. 
Technical Specifications

1. A specially designed stainless steel fume hood was used to create the testing environment. The size of the fume hood met the testing requirements. The test bench was placed in a sealed environment within the fume hood for the test (the front door of the fume hood can be opened and closed, and there is an observation window; during the experiment, the fume hood fan is turned off and the door is closed). The air flow speed within 100 mm ± 5 mm of the experimental bench area is less than 0.02 m/s (the fume hood is placed in the laboratory, and both the laboratory and the fume hood are enclosed environments. The fume hood has ventilation holes that can connect with the laboratory air, but the wind speed is close to 0). The fume hood is equipped with an air duct that can be connected to the ventilation pipe of the laboratory for smoke exhaust. The air flow speed of the fume hood is 0.5 - 0.6 m/s. 
2. The equipment complies with GB/T 30661.10-2024 and ISO 16840-10:2024. 
3. The test bench complies with the provisions of ISO 8191-1. The test bench with a frame height of 450 mm ± 2 mm and a width of 450 mm ± 2 mm can be used for both horizontal and vertical tests. 
4. Timer range: 0 - 99.99 seconds/minute/hour, accuracy: ±0.01 seconds. 
5. Heating source: Utilizes imported temperature controller and thermal sensor heating element: HotSet HotControl C248, which consists of two parts. 
a) Thermal source compliance: 
— Diameter: 8 mm ± 0.5 mm; 
—The heating length is 75 mm ± 5 mm; 
—The heat power is 200 W ± 20 W; 
—Integrate K-type thermocouples at the heat source center; 
—The shortest length of the wire is 3 meters. 
—Heat-resistant wires are made of insulating materials; 
The device used to fix the heat source during the experiment to prevent burns when operating the heat source. 
b) Temperature Controller: 
— Temperature controller that automatically detects and controls the temperature of the area or adjusts the controller parameters based on the model; 
During the test period, the temperature value changes automatically according to the preset temperature curve. 
6. Selection of testing procedures: 
(1) Level test: Test in the following order: 
a) In the testing environment, install the test sample on the testing platform or wheelchair vehicle, and set it to an angle of ±3° horizontally. 
b) Place the specified heat source at the center of the upper surface of the test sample, 50 mm ± 5 mm away from the surface, parallel to the upper surface of the test sample; apply a force of 0.1 to 0.5 N to ensure that there is as little gap as possible between the heat source and the upper surface of the test sample during the test, and ensure that the heat source remains in contact with the sample throughout the entire test process. 
c) Turn on the heat source switch. When the temperature reaches the initial point of 575°C ± 30°C, the test phase begins. Observe the subsequent combustion process and record the data of the developing smoldering, or internal combustion and/or surface combustion. Remove the heat source 60 seconds later. Ignore the residual light, smoke, or smoldering that stops within 20 seconds after the end of the high-temperature section of the heating temperature curve. 
d) Repeat steps a) to c) using the same sample in an unaffected area or a new sample. Ensure that there is no carbon buildup on the heat source between the two tests. 
(2) Vertical test: Conduct the test in accordance with the standard requirements: 
a) The test bench is placed vertically (with the contact surface facing upwards). 
b) Place the specified heat source at the center of the test sample's width, ±5 mm from the edge, with the bottom facing upwards (0.1h + 20) mm ± 5 mm. 
c) Adjust the heat source within the horizontal plane to be within ±3° of the contact surface of the tested sample. Apply a force of 0.5 N ± 0.1 N to the heat source to ensure there is no gap between the heat source and the surface of the test sample. Also, ensure that the heat source remains in contact with the sample throughout the entire testing process. 
d) Turn on the power switch. When the initial point of a continuous temperature rise of 575°C ± 30°C is reached, the testing phase begins. Observe the subsequent combustion process and record the phenomena of developing smoldering, or internal combustion and/or surface combustion. Remove the heat source after 60 seconds. Ignore residual light, smoke, or smoldering that stops within 20 seconds after the end of the high-temperature section of the heating temperature curve. 
(e) Repeat steps a) to c) using the same sample in an unaffected area or a new sample. Ensure that there is no carbon buildup on the heat source between the two tests. 
(3) Test of smaller body support devices: 
According to the standard, if a body position support device is smaller than the specified size, during its use it may be exposed to the center of the maximum area of the fire source. In these cases, the dashed box represents the maximum area that may be exposed to the fire source, and the diamond point indicates the center of this area. The body position support device should be tested in its typical expected direction of use. 
7. Evaluation of Test Results: 
a) During the testing process or after the tests, there is no evidence suggesting that combustion can occur internally and/or on the surface. 
b) After the end of the high-temperature section of the heating temperature curve (20 ± 1) seconds later, there was no development of over-baking. 
8. Users are responsible for bringing their own personal protective equipment, etc. 
9. Working power supply: AC 220V, 50Hz. 

Wheelchair seat body position support device flame retardancy tester