Turn the temperature control knob fully counterclockwise ("O" reading). Advance the temperature control knob clockwise until the indicator light is illuminated. Advance the knob clockwise to the next numbered line. After the thermometer mercury column ceases to advance, record the dial reading and the temperature. Advance the knob clockwise to the next numbered line. After the thermometer mercury column ceases to advance, read the dial reading and the temperature. Repeat this procedure through the full range of the instrument. Plot the dial readings versus the respective temperatures.
where:
Sc = specification, or uncorrected target, flashpoint, °C,
Sf = specification, or uncorrected target, flashpoint, °F,
B = ambient barometric pressure, mm Hg, and
A = ambient barometer pressure, kPa.4
Where: F = Observed flashpoint, °F,
C = observed flashpoint, °C,
B = ambient barometric pressure, mm Hg; and
A = ambient barometric pressure, kPa.
Table 1-Calibration of Tester
Material | p-xyleneA (Caution).B |
Specific gravity. 15.6/15.6 °C (60/60 °F) | 0.850 to 0.866. |
Boiling range | 2 °C maximum including 138.35 °C (281.03 °F). |
Freezing point | 11.23 °C (52.2 °F) minimum. |
Flashpoint °C (acceptable range) | 25.6 ±0.5 (78 ±1 [PHI]). |
A Available as Flash Point Check Fluid (p-xylene) from Special Products Div., Phillips Petroleum Co., Drawer 'O,' Borger, Texas 79007.
B Caution: Handle xylene with care. Avoid inhalation; use only in a well-ventilated area. Avoid prolonged or repeated contact with skin. Keep away from flames and heat, except as necessary for the actual flash point determination.
Table 2-Repeatability and Reproducibility
Temperature, °C (°F) | Repeatability, °C (°F) | Reproducibility, °C (°F) |
20(68) | 0.5(0.9) | 1.4(2.6) |
70(158) | 0.5(0.9) | 2.9(5.3) |
93(200) | 1.3(2.3) | 4.9(8.8) |
150(300) | 2.0(3.6) | 7.5(13.5) |
200(400) | 2.6(4.7) | 9.9(17.9) |
260(500) | 3.3(5.9) | 12.4(22.3) |
Table 3-Essential Dimensions of Flash Test ApparatusA B
Sample Block | |
Block diameter | 61.5-62.5 |
Sample well diameter | 49.40-49.70 |
Sample well depth | 9.70-10.00 |
Top of block to center of thermometer hole | 16.00-17.00 |
Diameter of thermometer hole (approx.) | 7.0004 |
Cover | |
Large opening length | 12.42-12.47 |
Large opening width | 10.13-10.18 |
Small opening length | 5.05-5.10 |
Small opening width | 7.60-7.65 |
Distance between extreme edges of small openings | 48.37-48.32 |
Filling orifice diameter | 4.00-4.50 |
Bore or filler tube | 1.80-1.85 |
Maximum distance of filler tube from base of well with cover closed (max.) | 0.75 |
Slide | |
Large opening length | 12.42-12.47 |
Large opening width | 10.13-10.18 |
Small opening length | 5.05-5.10 |
Small opening width | 7.60-7.65 |
Near edge of large opening to end of slide | 12.80-12.85 |
Extremes of large and small openings | 30.40-30.45 |
Jet | |
Length of jet | 18.30-18.40 |
External diameter at end of jet | 2.20-2.60 |
Bore of jet | 1.60-1.65 |
Height of jet center above top surface of cover | 11.00-11.20 |
Jet pivot to center of block with cover closed | 12.68-12.72 |
A The O-seal or gasket which provides a seal when the cover is shut, should be made of a heat-resistant material capable of withstanding temperatures up to 150 °C for the low-range apparatus.
B When in position, the thermometer bulb should be surrounded with heat-conducting thermoplastic compound, such as a paste comprised of zinc oxide and mineral oil.
16 C.F.R. §1500.43a