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1. Ensure that the sample holder (the stand and clamp) is positioned in such a way that the sample will be held at least 425 mm above the working surface.
2. Place cotton pads directly below the clamp ensuring a 50mm x 50mm area is covered. Additionally, the thickness of the cotton should not exceed 6 mm.
3. Check that the valves for main and pilot at the back of the flame control module are closed. 
4. Use provided calibration strip (metal strip of specimen dimensions) in steps 5-12 to properly align the burner to sample. Once the apparatus is in alignment, begin at step 10 using the test specimen. 
5. Open the house gas line by moving the handle into the open position (parallel to the pipe). This valve is along the wall near the fume hood. Additionally the gas valve on the fume hood needs to be opened. Currently no gas should be going through the Bunsen burners as the valves on the UL94 apparatus should have been closed after testing finished. 
6. First open the gas line to the pilot flame by turning the knob labeled pilot at the back of the apparatus. Use the lighter to ignite the pilot. Adjust the flame height by opening or closing the pilot valve.
7. Partially open the valve to the main Bunsen burner. No gas will flow until the switch on the controller is flipped on.
8. Flip the switch on the bottom of the controller to start the flow of gas to the main burner. The pilot burner should ignite the main burner. If it does not, adjust the height of the pilot flame. Note the gas will only flow for 11.4 seconds. If additional time is needed, press the reset button at the top of the controller’s front panel. Use this time to adjust the flame height of the burner via the valve at the back of the controller. It should be a 20 1 20±1 mm high blue flame.
9. Once the settings on both valves are adjusted, flip the switch to turn off the test.
10. Place the top 6 mm of the specimen vertically in the clamp. Adjust the holder so that the bottom edge of the specimen is 300  10mm 300±10 mm above the cotton as shown in Figure 1

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1. Figure 1

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2. Start the burning portion of the test by flipping the switch. 
3. Apply the flame to the midpoint of the bottom edge of the specimen for 10 010±0.5 seconds. The application point should be 101mm 10±1mm above the top the Bunsen burner. The apparatus should be set up close to these specifications already, but the burner will be on for 11.4 seconds. This will allow for minor adjustments to be made.  Additionally the Bunsen burner should be angled up to 45° to prevent dripping onto to the Bunsen burner. If dripping is present, it should fall onto the cotton underneath the specimen.    
4. A timer will start on the controller after the 11.4 seconds of burning finishes. If an additional timer is being used, start it when the burner extinguishes.
5. At this time, the specimen is most likely flaming. When the flaming burn stops, record this time as t1 and reapply the burner for another 10010±0.5 seconds. To reapply the flame, use the reset button at the top of the controller.
6. If there is no flaming burn ceases immediately on the specimen after the first removal of the Bunsen burner flame, immediately reapply the flame.
7. After removing the flame for the second time, the timer should be reset. This happened happens on the controller automatically when the reset button was is pressed. Record the end of the flaming burn as t2.  
8. Without resetting the timer, watch for the end of the glowing burn period. Record the end of the glowing burn as time t3.
9. Record whether or not any flaming or glowing combustion smoldering has traveled up to the holding clamp.
10. Record whether or not the cotton beneath the sample was ignited from the specimen dripping.
    
    

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    Figure 1: Schematic for UL94 Burn Test

Results

The following results should be recorded:

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If only one specimen from a set of five specimens does not comply with the requirements, another set of five specimens is to be tested.

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