Pt. 63, Subpt. NNN, App. A
Appendix A to Subpart NNN of Part 63
—Method for the Determination of LOI
The purpose of this test is to determine the LOI of cured blanket insulation. The method is applicable to all cured board and blanket products.
2.1Scale sensitive to 0.1 gram.
2.2Furnace designed to heat to at least 540 °C (1,000 °F) and controllable to ±10 °C (50 °F).
2.3Wire tray for holding specimen while in furnace.
3.1Cut a strip along the entire width of the product that will weigh at least 10.0 grams. Sample should be free of dirt or foreign matter.
Remove all facing from sample.
3.2Cut the sample into pieces approximately 12 inches long, weigh to the nearest 0.1 gram and record. Place in wire tray. Sample should not be compressed or overhang on tray edges.
On air duct products, remove shiplaps and overspray.
3.3Place specimen in furnace at 540 °C (1,000 °F), ±10 °C (50 °F) for 15 to 20 minutes to insure complete oxidation. After ignition, fibers should be white and should not be fused together.
3.4Remove specimen from the furnace and cool to room temperature.
3.5Weigh cooled specimen and wire tray to the nearest 0.1 gram. Deduct the weight of the wire tray and then calculate the loss in weight as a percent of the original specimen weight.