ISO 2719 Determination of flash point - Pensky-Martens closed cup method
11 Calculation
11.1 Conversion of barometric pressure reading
If the barometric pressure reading is measured in a unit other than kilopascals, convert to kilopascals using one of the following conversions:
Reading in hPa x 0,1 = kPa,
Reading in mbar x 0,1 = kPa, or
Reading in mmHg x 0,133 3 = kPa.

11.2 Correction of observed flash point to standard atmospheric pressure
Calculate the corrected flash point, Tc, using Formula below:
Tc = Td + 0,25 x (101,3 - p)
Td is the detected flash point, expressed in °C;
p is the absolute barometric pressure, expressed in kPa;
0,25 is a constant, expressed in °C/kPa;
101,3 is used as the standard atmospheric pressure, expressed in kPa.

NOTE The above formula has been proven for barometric pressures down to 82,0 kPa and is strictly correct only up to 104,7 kPa.

12 Expression of results
Report the flash point, corrected to standard atmospheric pressure, rounded to the nearest 0,5 °C.

13 Precision
13.1 General
The precision, as determined by statistical examination according to ISO 4259 of interlaboratory test results, is given in 13.2 and 13.3.

NOTE The precision for in-process lubricating oils, such as those tested using Procedure A as part of a lubricant monitoring scheme, has not been determined.

13.2 Repeatability, r
The difference between two test results obtained by the same operator with the same apparatus under constant operating conditions on identical test material would, in the long run and in normal and correct operation of the test method, exceed the values given in Tables 1, 2 and 3 in only one case in 20.

13.3 Reproducibility, R
The difference between two single and independent test results obtained by different operators working in different laboratories on identical test material would in the long run, in the normal and correct operation of the test method, exceed the values given in Tables 4, 5 and 6 in only one case in 20.

14 Test report
The test report shall contain at least the following information:
a) a reference to this International Standard, i.e. ISO 2719, and the procedure used;
b) the type and complete identification of the sample tested;
c) the pre-heat temperature and pre-heat time, if applicable (see 9.1.4);
d) the ignitor type (gas or electric);
e) the laboratory absolute barometric pressure (see 10.2.1, 10.3.1 and 10.4.1);
f) the result of the test (see Clause 12);
g) any deviation, by agreement or otherwise, from the procedure specified;
h) the date of the test.