D92_A1 (16b)

Test cup conforming to figure 3 with dimensions as shown with the figure-- the cup shall be made of brass or other non-rusting metal of equivalent heat conductivity. The cup may be equipped with a handle. The heating plate shall be of sufficient dimension and materials to ensure that thermal heat to the test cup is only applied to the bottom of the test cup, and that extraneous heat to the test cup other than that to the bottom is minimized. An example for manual apparatus that utilize Bunsen burners or exposed electric heating elements is shown in figure 2. Ignition source applicator-- the device for applying the test flame may be of any suitable type. When using a test flame, it is suggested that the tip be 1.6 plus or minus 0.05 millimeters, or 1/16 of an inch, in diameter at the end, and that the orifice be approximately 0.8 plus or minus 0.05 millimeters, or 1/32 of an inch, in diameter. The device for operating the test flame applicator may be mounted in such a manner as to permit automated duplication of the sweep of the test flame, the radius of swing being not less than 150 millimeters, or 6 inches. The center of the test flame should be supported so that it swings in a plane not greater than 2 millimeters, or 5/64 of an inch, above the plane of the rim of the cup. It is desired that a bead having a diameter of 3.2 to 4.8 millimeters, or 1/8 to 3/16 of an inch, be mounted in a convenient position on the apparatus so that the size of the test flame can be compared to it. A test flame relighting device such as a pilot flame is sometimes used to automatically relight the test flame in the event that it is extinguished during the test. This device should be designed such that the unburned gas will not spread out over the test cup during the relighting. Heater-- heat may be supplied from any convenient source. The use of a gas burner or alcohol lamp is permitted, but under no circumstances are products of combustion or free flame to be allowed to come up around the cup. An electric heater which can be controlled automatically or controlled by the user is preferred. The source of the heat shall be centered under the opening of the heating plate with no local superheating. Flame-type heaters may be protected from drafts or excessive radiation by any suitable type of shield that does not project above the level of the upper surface of the heating plate. Temperature measuring device support-- any convenient device that will hold the temperature measuring device in a specified position during a test and that will permit easy removal of the temperature measuring device from the test cup upon completion of the test may be used. Heating plate support-- any convenient support that will hold the heating plate level and steady may be employed.