Flashpoint closed cup

ISO 1523-83. Paints, varnishes, petroleum and related products - Determination of flashpoint - Closed cup equilibrium 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. 

It is certainly this lack of clarity which leads to the current situation. Flashpoints are usually given without any mention of either the open or closed cup aspects or the make of apparatus. Amongst the thousand or so organic substances listed in Part Two, more than one hundred of them mention oc and cc , which enables comparisons to be made. Nevertheless, a study of the data indicates that the difference between experimental values can reach 56°C for the same substance (for instance, butadiene). It happens quite often that for flashpoints lower values oc than cc values for the same substance are found.The nature of the sources of the level of measurement error in flashpoints can easily be guessed at. 

Flashpoint No data No data No data 93 C (closed cup) 85 C (open cup)... 

Using data in Table 6.1, calculate the closed cup flashpoint of n-octane. Compare your results with the value given in Table 6.1. 

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. 

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). 

BSI 1998b. Methods of Analysis of Fats and Fatty Oils, Part 1. Physical Methods, Section 1.17. Flashpoint limit test using Pensky-Martens closed-cup flash tester, British Standards Institution, London. 

Flashpoint NFPA Hazard Classification -11 °C (closed cup) Merck 1989... 

The flashpoint is a measure of the ease of ignition of a liquid. It is the lowest temperature at which the material will ignite from an open flame. The flashpoint is a function of the vapor pressure and the flammability limits of the material. It is measured in standard apparatus, following standard procedures (ASTM D92 and ASTM D93). Both open- and closed-cup apparatus is used. Closed-cup flashpoints are lower than open cup, and the type of apparatus used should be stated clearly when reporting measurements. Flashpoints are given in Sax s Handbook of Hazardous Materials (Lewis, 2004). The flashpoints of many volatile materials are below normal ambient temperature, for example, ether —45°C, gasoline —43°C (open cup). 

Usually, flashpoint is measured in air. Open cup methods may overestimate the flashpoint for liquids containing multiple components because of the loss of more volatile components during testing. Nevertheless, open cup testers can provide flashpoint for situations of open vessels and spills. In contrasts, closed cup techniques prevent the loss of volatile components by keeping the sample enclosed until the ignition source is introduced, and therefore, closed cup data are more conservative than and generally preferred to open cup data. 

ASTM D93-02. Standard Test Methods for Flashpoint by Pensky-Martens Closed Cup Tester, ASTM International West Conshohocken, PA, USA, 2002 Edition. 

Class 3 deals with liquids, or mixtures of liquids, or liquids containing solids in solution or suspension (e g. paints, varnishes, lacquers, etc., but not including substances which, on account of their other dangerous characteristics, have been included in other classes) which give off a flammable vapour at or below 61°C (141 F) closed cup test (corresponding to 65.6°C (150°F) open cup test), normally referred to as the flashpoint. IMO Class 3,1.1... 

Cleveland O.C., no flashpoint observed up to the boiling point using Setaflash closed cup. 

DIN EN 22719-93. Petroleum products and lubricants. Determination of flashpoint. Pensky-Martens closed cup method (ISO 2719). 

---