Closed cup tests

From the point of view of the potential for a fire, the closed cup flash point determination is usually the most important. In a perfect closed cup test, the vapor pressure is in equilibrium with the liquid at the temperature of the test. At the flash point, the vapor composition is at the lower flammable limit. In fact, the lower flammable limit can be estimated from vapor pressure data (for a pure compound). Open cup flash points are generally higher and, thus less conservative, than closed cup determinations. The value determined in an open cup test is subject to air movement at the open face of the cup and true vapor-liquid equilibrium probably does not occur. 

Liquid, or mixtures of liquids, or liquids containing solids in solution or suspension which give off a flammable vapor at temperatures of not more than 60.5°C, closed-cup test, or not more than 65.6°C, open-cup test. 

Flash point of 140 ° F or lower in the closed-cup test method, or easy, spontaneous thermal reaction. 

If data are not available, the flash point and the initial boiling point shall be determined through testing. The flash point shall be determined by closed-cup test method. Open-cup tests are acceptable only in special cases. 

The US EPA has identified four properties of ignit-ibility. One of the four properties pertains to liquids that are not aqueous solutions containing less than 24% alcohol by volume. A liquid meeting this description that has a flash point <60°C (I40°E), as determined by a specified closed cup test, is one example of an ignitible hazardous waste that carries the waste code DOOI. 

Flammable liquids are liquids, or mixtures of liquids, or liquids containing solids in solution or suspension (for example paints, varnishes, lacquers, etc., but not including substances otherwise classified on account of their dangerous characteristics) which give off a flammable vapour at temperatures of not more than 60.5°C, closed-cup test, or not more than 65.6°C, open-cup test, normally referred to as the flash point. [Text continues.] UN 2.3.1.1... 

NFPA developed a classification system for flammable liquids and combustible liquids (see Table 16-3) that uses flash point, vapor pressure, and expected ambient temperature conditions. A flammable liquid is a liquid with a flash point that does not exceed 100 °F based on testing by closed-cup test methods. A combustible liquid is a liquid with a flash point at 100 °F or higher using the same test methods. The flash point of a liquid is the lowest temperature at which the vapor pressure of the liquid is just sufficient to produce a... 

The flash point, denoted PP or jp, expressed in K( C), is the temperature at which a pool of a flammable liquid will generate sufficient vapors to form an ignitable vapor/air mixture. It can also be seen as the temperature at which a liquid will reach its lower flammabihty limit (LFL) in air. However, flammable liquids can also ignite below their flash point if the surface area is increased either by dispersion (e.g., aerosol) or by mechanical activation (e.g., spraying) that raises the concentration of vapor in air above the lower flammability limit. In practice the flash point of a liquid is measured following standardized laboratory test protocols such as the Continuously Closed Cup Test (ASTM D6450), the Pensky-Martens Closed Cup Test (ASTM D93) or by the Tag Closed Cup Test (ASTM D56). 

Flash Point Closed is determined by heating the oil in a closed cup test-flame is injected into the cup through an opening produced temporarily and ignition of vapour takes place inside the cup. Thus, the vapour is not... 

---