Closed Cup Method

The flash points obtained experimentally according to the different procedures differ slightly. The present estimation refers to the flash point called the closed cup method. 

The U.S. domestic shipping name of isopropyl alcohol is UN No. 1219 Isopropanol. Anhydrous as well as water solutions to 91 vol % alcohol are considered flammable Hquid materials by the DOT. Both have flash poiats below 37.8°C by the Tag closed-cup method. Acceptable modes of transportation include air, rail, road, and water (124). For international air and water shipments, the International Maritime Organization (IMO) class is 3.2, the packaging group is II, and the primary hazard label required is "Flammable Liquid."... 

Commercial ethyl alcohol is shipped in railroad tank cars, tank tmcks, 208-L (55-gal) and 19-L (5-gal) dmms, and in smaller glass or metal containers having capacities of 0.473 L (one pint), 0.946 L (one quart), 3.785 L (one U.S. gal), or 4.545 L (one Imperial gal). The 208-L dmms may be of the unlined iron type. If a guarantee of more meticulous quaUty is desired, the dmms may be lined with phenoHc resin. AH containers, of course, must comply with the specifications of the U.S. Department of Transportation. Both 190 proof and 200 proof ethyl alcohol are considered red label (flammable) materials by the DOT, as both have flash points below 37.8°C by the Tag closed-cup method. 

Flashpoint — the lowest temperature of a liquid at whieh it gives off enough vapor to form an ignitable mixture with air near the surfaee of the liquid within the vessel used. Two tests are used—Open Cup and Closed Cup. Generally, the Open Cup method results in flashpoints 5° to 10° higher than the Closed Cup method. Flashpoint < 140°F (Closed Cup) is the eriterion used by EPA to deeide whether a ehemieal is hazardous by ignitability. DOT defines materials with flashpoints of < 100°F as flammable materials, and between 100° and 200°F as eombustible. 

Flash point of a flammable liquid The lowest temperature at which the liquid gives off enough vapors to form a flammable mixture with air (or pure oxygen, a special case) at or near the surface of the liquid or within its confined container. Some hazardous liquids have flash points at or below ordinary room temperatures and normally are covered by a layer of flammable vapors that will ignite immediately if a source of ignition is brought in contact [32]. Flash points are measured by open cup and closed cup methods. The open cup data is applicable to liquid in open containers and in open pools and usually somewhat higher temperatures than the closed cup. Refer to... 

The flash pt for IPN using the Abel closed cup method is 53°F while the Cleveland open cup method gives a value of 72°F. Min spont ign temp range in air on a heated brass, Al stainless steel or mild steel plate is 245—60° The following data from Ref 6 present, in tabular form, the limits of flammability of IPN vapor/air mixts over a press and temp range ... 

Methods of test for petroleum and its products. Determination of flash point. Pensky-Martens closed cup method. 

The lowest temperature of a flammable liquid at which it gives off sufficient vapor to form an ignitable mixture with the air near the surface of the liquid or within the vessel used. The flash point has been commonly determined by the open cup or closed cup method but recent research has yielded higher and lower flash points dependent on the surface area of the ignition source. Because of this aspect ASTM and other standard test methods have been recently withdrawn. They are under review until an adequate determination of a practical and comprehensive standard is composed and agreed upon. 

FLASHPOINT (Method Used) The flashpoint of the mixture has been determined to be 168 F (75.5 C) by the closed cup method. The lowest flashing component of the mixture (ethylene glycol monomethyl ether) has a flashpoint of 115 F (46 C) by the closed cup method. 

Hughes, J.M., Hardy, D.R., and Beal, EJ. A flash point value for n-dodecane based on the manual Pensky-Martens closed cup method (ASTM-D-93), Energy Fuels, 10(6) 1276-1277, 1996. 

These are liquids, mixtures of liquids, or liquids containing solids in solution or in suspension. The flash point of these materials is 140°F (60°C) or less by the closed-cup method or 150°F (65.5°C) or less by the open-cup method. 

The flash point is a measured temperature at which vapors above the surface of a liquid are just sufficiendy concentrated to propagate a flame (10). In practice, materials of concern may be in closed or open containers or may have spilled. Generally, the chosen flash point method should be related to the problem as well as to the type of material ie, open-cup methods are more significant for open containers or spills, whereas closed-cup methods give more significant information for closed containers, eg, process vessels. A number of commercial flammable liquids contain a moderate amount of noncombustible components, eg, chlorinated hydrocarbons, in order to elevate the closed-cup flash point and thus gain a more favorable classification. When the same material is analyzed by an open-cup method, the flash point is not elevated, ie, after a spill, the noncombustible material would soon be lost and the residue may be highly flammable. 

For applicability and limitations of each test, consult the reactive chemicals testing supervisor or refer to the appropriate ASTM standards. In addition, ASTM E502 reviews the closed-cup methods and discusses potential problems with testing mixtures. 

CC Closed Cup method for the measurement of the flash point. With this method, Sample vapors are not allowed to escape as they can with the open cup method. Because of this, flash points measured with the CC method are usually a few degrees lower than those measured with the OC. The choice between CC and OC is dependent on the (usually ASTM) standard method chosen for the test. 

Hydrolytic stability. The test method required treating the fluids with 0.1% water and maintaining the fluid at 77°C for up to 200 h. Samples were withdrawn at 20-h intervals, and the flash points were measured by the closed cup method. A decrease in flash point was interpreted as being indicative of hydrolytic breakdown to form low molecular weight products. The PAO showed no decrease in flash point under any of the test conditions. 

Standard methods for the determination of the critical temperatures are published by the AOCS (AOCS Official Methods Cc 9a 48 (smoke, flash and fire points by an open cup method), and Cc 9b-55 and Cc 9c 95 (flash point by open cup methods), Firestone, 1998) and by the British Standards Institution (BS 684 Section 1.8 1976 (smoke point), BSI, 1976b and BS 684-1.17 1998/ISO 15267 1998 (flashpoint by a closed cup method), BSI, 1998b). 

Hash point measurements from the closed-cup method are quoted unless only data from the open-cup (oc) method are available. Data from Stephenson, R. M., Flash Points of Organic and Organometallic Compounds (New York Elsevier, 1987) Bond, J., Sources of Ignition (Oxford Butterworth, 1991). 

Of the available test methods, the most common method of determining the flash point confines the vapor (closed cup method) until the instant the flame is applied (ASTM D-56, ASTM D-93, ASTM D-3828,6450, IP 34, IP 94, IP 303) (Fig. 4.5). An alternate method that does not confine the vapor... 

Method 1P34. Determination of Idash Point - Pensky Martens Closed Cup Method. IP Standard Methods for Analysis and Testing of Petroleum and Related Products and British Standard 2000 Parts. Energy Institute. 

Flash Point. Flash points were determined by the Tag closed cup method (16) rather than by the Pensky-Martens method (20) as called for in the specifications for JP-5 (3) and DFM (5). The Tag closed cup, however, is specified for JP-8 ( 4). 

Physical Parameters. It is obtained as a liquid, but forms laminar crystals at low temperature having mp 20.5°C. It has physical parameters as d l 1.033 bp 202°C and n 1.533 g. Its flash point when determined by closed cup method is found to be 105°C. It is slightly soluble in water and freely soluble in alcohol, chloroform, glycerol, fatty oils and ether. Its solution in concentrated HgSO gives a distinct orange colouration. 

DIN EN ISO 2719 2003-09 (2002) Determination of flash point—Pensky-Martens closed cup method (ISO 2719 2002) German version EN ISO 2719 2002... 

Note Flash points are determined by the ASTM Pensky-Martens Closed Cup Method and fire points by the ASTM Cleveland Open Cup Method. 

Melting point Cleveiand open cup Pensky Martens closed cup Flash points measured by the closed cup method. ASTM D-56 ... 

AS/NZS 2106.1-99. Methodsforthedeterminationoftheflashpoint of flammable hquids (closed cup)-Abel closed cup method. 

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