Flash-point corrections

A2.1.1 Typical values of the flash point corrected for baromdiic pressure for some reference materials and their typical limits are given in Table A2.1 (see Note A2.3). Suf liers of CRMs will provide certificates stating the m od-spedfic fiash point for each material of the current production batch. Calculation of the limits for these other CRMs can be determined fix>m the reprodudbility value of this test method, reduced by interlaboratory effect and then multiplied by 0.7 (see Research Report RR S1S-1007). 

Correction factor = 23— A where A = average observed flash point of n-heptane... 

Apply this correction to all flash point determinations between 0 and 60F (—17.8 to 15.6C). Round off corrections to the nearest whole number according to Recommended Practice E 29... 

It is important to note that the extinguishing techniques, controlling actions, or fire-prevention activities implemented can differ greatly depending upon which of the two categories the liquid falls in. To have the ability to categorize a liquid correctly when it is not so identified, it is only necessary to know its flash point. By definition, the flash point of a liquid determines whether a liquid is flammable or combustible. 

Flash point means the lowest temperature (corrected to a standard pressure of 101.3 kPa) at which the application of an ignition source causes the vapours of a liquid to ignite under specified test conditions ... 

Table 5A.—Stem Correction Data for Pensky-Martin Flash-point Apparatus Thermometer used up to 150 C., range 40 to 160°C. in 1 intervals, scale length 9.5 cm. Thermometer used from 200 to 300°, range 200 to 360° in 1° intervals, scale length 12 cm.

In both cases the flash point of the lubricant is likely to be reduced. If increased viscosity is due to carbonaceous insolubles, both viscosity and insolubles can often be reduced by correct centrifuging. 

The second-stage catalyst must also have essentially no acidity to prevent cracking of the feedstock and generation of light ends. It is normal to have a stripper at the end of the process to remove small amounts of light ends formed and correct the product flash point, but any further cracking would lead to unnecessary yield loss. 

Some special parameters (e.g., flash point, heating value, water content) must be determined for wastes that are to be disposed of or thermally utilized by combustion. All data for a given waste are documented in a multi-page survey form. The plant manager is responsible for the correctness of the information. After thorough checking, including a check for completeness of analysis data, the necessary pretreatment and the... 

The flash point of a liquid is the lowest temperature in °C corrected to 101.3 kPa of a flammable hquid in an open or closed cup at which vapours develop in such a quantity that under defined measuring conditions in the cup a vapour-air mixture is... 

For rapid determination of closed cup flash points between 5 and 105 °C, rapid equilibrium method, ISO 3679-1983, ASTM D 3941-1980, ASTM D 3828-1981), the Setaflash tester is recommended (Fig. 3.15). An aluminium block is heated to 3 °C below the expected flash point then 2 cm of the sample is injected into the sample hollow by a syringe. After 60 s, ignition is attempted by a 3.5-mm long test flame with a momentary opening of the sliding cover on the sample hollow. With repeated trials, the flash point is bracketed at first within 5 then within 1 C, using fresh sample portions in each test. For calculation of the closed cup flash point, the above barometric correction is again used. 

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